diff --git a/.github/CODEOWNERS b/.github/CODEOWNERS
new file mode 100644
index 0000000000..f9478d1369
--- /dev/null
+++ b/.github/CODEOWNERS
@@ -0,0 +1,2 @@
+beacon_node/network/                @jxs
+beacon_node/lighthouse_network/     @jxs
diff --git a/.github/workflows/book.yml b/.github/workflows/book.yml
index 031a88b03c..e9db3b6ab1 100644
--- a/.github/workflows/book.yml
+++ b/.github/workflows/book.yml
@@ -11,7 +11,7 @@ concurrency:
 
 jobs:
   build-and-upload-to-s3:
-    runs-on: ubuntu-20.04
+    runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@v4
 
diff --git a/.github/workflows/test-suite.yml b/.github/workflows/test-suite.yml
index 45f3b757e7..0ee9dbb622 100644
--- a/.github/workflows/test-suite.yml
+++ b/.github/workflows/test-suite.yml
@@ -392,6 +392,10 @@ jobs:
           cache: false
       env:
           GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+    - name: Fetch libssl1.1
+      run: wget https://nz2.archive.ubuntu.com/ubuntu/pool/main/o/openssl/libssl1.1_1.1.1f-1ubuntu2_amd64.deb
+    - name: Install libssl1.1
+      run: sudo dpkg -i libssl1.1_1.1.1f-1ubuntu2_amd64.deb
     - name: Create Cargo config dir
       run: mkdir -p .cargo
     - name: Install custom Cargo config
diff --git a/Cargo.lock b/Cargo.lock
index c62e9fbc87..20d2548d09 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -43,7 +43,6 @@ dependencies = [
 name = "account_utils"
 version = "0.1.0"
 dependencies = [
- "directory",
  "eth2_keystore",
  "eth2_wallet",
  "filesystem",
@@ -150,9 +149,9 @@ dependencies = [
 
 [[package]]
 name = "allocator-api2"
-version = "0.2.20"
+version = "0.2.21"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "45862d1c77f2228b9e10bc609d5bc203d86ebc9b87ad8d5d5167a6c9abf739d9"
+checksum = "683d7910e743518b0e34f1186f92494becacb047c7b6bf616c96772180fef923"
 
 [[package]]
 name = "alloy-consensus"
@@ -205,9 +204,9 @@ dependencies = [
 
 [[package]]
 name = "alloy-primitives"
-version = "0.8.12"
+version = "0.8.19"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "9fce5dbd6a4f118eecc4719eaa9c7ffc31c315e6c5ccde3642db927802312425"
+checksum = "ec878088ec6283ce1e90d280316aadd3d6ce3de06ff63d68953c855e7e447e92"
 dependencies = [
  "alloy-rlp",
  "arbitrary",
@@ -217,10 +216,9 @@ dependencies = [
  "derive_arbitrary",
  "derive_more 1.0.0",
  "foldhash",
- "getrandom",
- "hashbrown 0.15.1",
- "hex-literal",
- "indexmap 2.6.0",
+ "getrandom 0.2.15",
+ "hashbrown 0.15.2",
+ "indexmap 2.7.1",
  "itoa",
  "k256 0.13.4",
  "keccak-asm",
@@ -229,7 +227,7 @@ dependencies = [
  "proptest-derive",
  "rand",
  "ruint",
- "rustc-hash 2.0.0",
+ "rustc-hash 2.1.0",
  "serde",
  "sha3 0.10.8",
  "tiny-keccak",
@@ -237,9 +235,9 @@ dependencies = [
 
 [[package]]
 name = "alloy-rlp"
-version = "0.3.9"
+version = "0.3.11"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "da0822426598f95e45dd1ea32a738dac057529a709ee645fcc516ffa4cbde08f"
+checksum = "3d6c1d995bff8d011f7cd6c81820d51825e6e06d6db73914c1630ecf544d83d6"
 dependencies = [
  "alloy-rlp-derive",
  "arrayvec",
@@ -248,13 +246,13 @@ dependencies = [
 
 [[package]]
 name = "alloy-rlp-derive"
-version = "0.3.9"
+version = "0.3.11"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "2b09cae092c27b6f1bde952653a22708691802e57bfef4a2973b80bea21efd3f"
+checksum = "a40e1ef334153322fd878d07e86af7a529bcb86b2439525920a88eba87bcf943"
 dependencies = [
  "proc-macro2",
  "quote",
- "syn 2.0.89",
+ "syn 2.0.96",
 ]
 
 [[package]]
@@ -319,19 +317,20 @@ dependencies = [
 
 [[package]]
 name = "anstyle-wincon"
-version = "3.0.6"
+version = "3.0.7"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "2109dbce0e72be3ec00bed26e6a7479ca384ad226efdd66db8fa2e3a38c83125"
+checksum = "ca3534e77181a9cc07539ad51f2141fe32f6c3ffd4df76db8ad92346b003ae4e"
 dependencies = [
  "anstyle",
+ "once_cell",
  "windows-sys 0.59.0",
 ]
 
 [[package]]
 name = "anyhow"
-version = "1.0.93"
+version = "1.0.95"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "4c95c10ba0b00a02636238b814946408b1322d5ac4760326e6fb8ec956d85775"
+checksum = "34ac096ce696dc2fcabef30516bb13c0a68a11d30131d3df6f04711467681b04"
 
 [[package]]
 name = "arbitrary"
@@ -523,7 +522,7 @@ checksum = "965c2d33e53cb6b267e148a4cb0760bc01f4904c1cd4bb4002a085bb016d1490"
 dependencies = [
  "proc-macro2",
  "quote",
- "syn 2.0.89",
+ "syn 2.0.96",
  "synstructure",
 ]
 
@@ -535,7 +534,7 @@ checksum = "7b18050c2cd6fe86c3a76584ef5e0baf286d038cda203eb6223df2cc413565f7"
 dependencies = [
  "proc-macro2",
  "quote",
- "syn 2.0.89",
+ "syn 2.0.96",
 ]
 
 [[package]]
@@ -568,7 +567,7 @@ dependencies = [
  "futures-lite",
  "parking",
  "polling",
- "rustix 0.38.41",
+ "rustix 0.38.44",
  "slab",
  "tracing",
  "windows-sys 0.59.0",
@@ -580,20 +579,31 @@ version = "3.4.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "ff6e472cdea888a4bd64f342f09b3f50e1886d32afe8df3d663c01140b811b18"
 dependencies = [
- "event-listener 5.3.1",
+ "event-listener 5.4.0",
  "event-listener-strategy",
  "pin-project-lite",
 ]
 
 [[package]]
-name = "async-trait"
-version = "0.1.83"
+name = "async-recursion"
+version = "1.1.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "721cae7de5c34fbb2acd27e21e6d2cf7b886dce0c27388d46c4e6c47ea4318dd"
+checksum = "3b43422f69d8ff38f95f1b2bb76517c91589a924d1559a0e935d7c8ce0274c11"
 dependencies = [
  "proc-macro2",
  "quote",
- "syn 2.0.89",
+ "syn 2.0.96",
+]
+
+[[package]]
+name = "async-trait"
+version = "0.1.85"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "3f934833b4b7233644e5848f235df3f57ed8c80f1528a26c3dfa13d2147fa056"
+dependencies = [
+ "proc-macro2",
+ "quote",
+ "syn 2.0.96",
 ]
 
 [[package]]
@@ -620,6 +630,12 @@ dependencies = [
  "pin-project-lite",
 ]
 
+[[package]]
+name = "atomic-waker"
+version = "1.1.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "1505bd5d3d116872e7271a6d4e16d81d0c8570876c8de68093a09ac269d8aac0"
+
 [[package]]
 name = "attohttpc"
 version = "0.24.1"
@@ -644,13 +660,13 @@ dependencies = [
 
 [[package]]
 name = "auto_impl"
-version = "1.2.0"
+version = "1.2.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "3c87f3f15e7794432337fc718554eaa4dc8f04c9677a950ffe366f20a162ae42"
+checksum = "e12882f59de5360c748c4cbf569a042d5fb0eb515f7bea9c1f470b47f6ffbd73"
 dependencies = [
  "proc-macro2",
  "quote",
- "syn 2.0.89",
+ "syn 2.0.96",
 ]
 
 [[package]]
@@ -669,10 +685,10 @@ dependencies = [
  "axum-core",
  "bytes",
  "futures-util",
- "http 1.1.0",
+ "http 1.2.0",
  "http-body 1.0.1",
  "http-body-util",
- "hyper 1.5.1",
+ "hyper 1.6.0",
  "hyper-util",
  "itoa",
  "matchit",
@@ -702,7 +718,7 @@ dependencies = [
  "async-trait",
  "bytes",
  "futures-util",
- "http 1.1.0",
+ "http 1.2.0",
  "http-body 1.0.1",
  "http-body-util",
  "mime",
@@ -849,7 +865,7 @@ dependencies = [
  "genesis",
  "hex",
  "http_api",
- "hyper 1.5.1",
+ "hyper 1.6.0",
  "lighthouse_network",
  "monitoring_api",
  "node_test_rig",
@@ -918,7 +934,7 @@ version = "0.69.5"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "271383c67ccabffb7381723dea0672a673f292304fcb45c01cc648c7a8d58088"
 dependencies = [
- "bitflags 2.6.0",
+ "bitflags 2.8.0",
  "cexpr",
  "clang-sys",
  "itertools 0.12.1",
@@ -931,7 +947,7 @@ dependencies = [
  "regex",
  "rustc-hash 1.1.0",
  "shlex",
- "syn 2.0.89",
+ "syn 2.0.96",
  "which",
 ]
 
@@ -958,9 +974,9 @@ checksum = "bef38d45163c2f1dde094a7dfd33ccf595c92905c8f8f4fdc18d06fb1037718a"
 
 [[package]]
 name = "bitflags"
-version = "2.6.0"
+version = "2.8.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "b048fb63fd8b5923fc5aa7b340d8e156aec7ec02f0c78fa8a6ddc2613f6f71de"
+checksum = "8f68f53c83ab957f72c32642f3868eec03eb974d1fb82e453128456482613d36"
 
 [[package]]
 name = "bitvec"
@@ -1128,9 +1144,9 @@ dependencies = [
 
 [[package]]
 name = "bumpalo"
-version = "3.16.0"
+version = "3.17.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "79296716171880943b8470b5f8d03aa55eb2e645a4874bdbb28adb49162e012c"
+checksum = "1628fb46dfa0b37568d12e5edd512553eccf6a22a78e8bde00bb4aed84d5bdbf"
 
 [[package]]
 name = "byte-slice-cast"
@@ -1146,9 +1162,9 @@ checksum = "1fd0f2584146f6f2ef48085050886acf353beff7305ebd1ae69500e27c67f64b"
 
 [[package]]
 name = "bytes"
-version = "1.8.0"
+version = "1.9.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "9ac0150caa2ae65ca5bd83f25c7de183dea78d4d366469f148435e2acfbad0da"
+checksum = "325918d6fe32f23b19878fe4b34794ae41fc19ddbe53b10571a4874d44ffd39b"
 dependencies = [
  "serde",
 ]
@@ -1200,9 +1216,9 @@ dependencies = [
 
 [[package]]
 name = "cargo-platform"
-version = "0.1.8"
+version = "0.1.9"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "24b1f0365a6c6bb4020cd05806fd0d33c44d38046b8bd7f0e40814b9763cabfc"
+checksum = "e35af189006b9c0f00a064685c727031e3ed2d8020f7ba284d78cc2671bd36ea"
 dependencies = [
  "serde",
 ]
@@ -1215,7 +1231,7 @@ checksum = "eee4243f1f26fc7a42710e7439c149e2b10b05472f88090acce52632f231a73a"
 dependencies = [
  "camino",
  "cargo-platform",
- "semver 1.0.23",
+ "semver 1.0.25",
  "serde",
  "serde_json",
  "thiserror 1.0.69",
@@ -1229,9 +1245,9 @@ checksum = "37b2a672a2cb129a2e41c10b1224bb368f9f37a2b16b612598138befd7b37eb5"
 
 [[package]]
 name = "cc"
-version = "1.2.1"
+version = "1.2.10"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "fd9de9f2205d5ef3fd67e685b0df337994ddd4495e2a28d185500d0e1edfea47"
+checksum = "13208fcbb66eaeffe09b99fffbe1af420f00a7b35aa99ad683dfc1aa76145229"
 dependencies = [
  "jobserver",
  "libc",
@@ -1285,9 +1301,9 @@ dependencies = [
 
 [[package]]
 name = "chrono"
-version = "0.4.38"
+version = "0.4.39"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "a21f936df1771bf62b77f047b726c4625ff2e8aa607c01ec06e5a05bd8463401"
+checksum = "7e36cc9d416881d2e24f9a963be5fb1cd90966419ac844274161d10488b3e825"
 dependencies = [
  "android-tzdata",
  "iana-time-zone",
@@ -1355,9 +1371,9 @@ dependencies = [
 
 [[package]]
 name = "clap"
-version = "4.5.21"
+version = "4.5.27"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "fb3b4b9e5a7c7514dfa52869339ee98b3156b0bfb4e8a77c4ff4babb64b1604f"
+checksum = "769b0145982b4b48713e01ec42d61614425f27b7058bda7180a3a41f30104796"
 dependencies = [
  "clap_builder",
  "clap_derive",
@@ -1365,9 +1381,9 @@ dependencies = [
 
 [[package]]
 name = "clap_builder"
-version = "4.5.21"
+version = "4.5.27"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "b17a95aa67cc7b5ebd32aa5370189aa0d79069ef1c64ce893bd30fb24bff20ec"
+checksum = "1b26884eb4b57140e4d2d93652abfa49498b938b3c9179f9fc487b0acc3edad7"
 dependencies = [
  "anstream",
  "anstyle",
@@ -1378,21 +1394,21 @@ dependencies = [
 
 [[package]]
 name = "clap_derive"
-version = "4.5.18"
+version = "4.5.24"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "4ac6a0c7b1a9e9a5186361f67dfa1b88213572f427fb9ab038efb2bd8c582dab"
+checksum = "54b755194d6389280185988721fffba69495eed5ee9feeee9a599b53db80318c"
 dependencies = [
  "heck 0.5.0",
  "proc-macro2",
  "quote",
- "syn 2.0.89",
+ "syn 2.0.96",
 ]
 
 [[package]]
 name = "clap_lex"
-version = "0.7.3"
+version = "0.7.4"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "afb84c814227b90d6895e01398aee0d8033c00e7466aca416fb6a8e0eb19d8a7"
+checksum = "f46ad14479a25103f283c0f10005961cf086d8dc42205bb44c46ac563475dca6"
 
 [[package]]
 name = "clap_utils"
@@ -1453,9 +1469,9 @@ dependencies = [
 
 [[package]]
 name = "cmake"
-version = "0.1.51"
+version = "0.1.53"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "fb1e43aa7fd152b1f968787f7dbcdeb306d1867ff373c69955211876c053f91a"
+checksum = "e24a03c8b52922d68a1589ad61032f2c1aa5a8158d2aa0d93c6e9534944bbad6"
 dependencies = [
  "cc",
 ]
@@ -1493,9 +1509,9 @@ dependencies = [
 
 [[package]]
 name = "const-hex"
-version = "1.13.2"
+version = "1.14.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "487981fa1af147182687064d0a2c336586d337a606595ced9ffb0c685c250c73"
+checksum = "4b0485bab839b018a8f1723fc5391819fea5f8f0f32288ef8a735fd096b6160c"
 dependencies = [
  "cfg-if",
  "cpufeatures",
@@ -1549,9 +1565,9 @@ dependencies = [
 
 [[package]]
 name = "cpufeatures"
-version = "0.2.16"
+version = "0.2.17"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "16b80225097f2e5ae4e7179dd2266824648f3e2f49d9134d584b76389d31c4c3"
+checksum = "59ed5838eebb26a2bb2e58f6d5b5316989ae9d08bab10e0e6d103e656d1b0280"
 dependencies = [
  "libc",
 ]
@@ -1655,18 +1671,18 @@ dependencies = [
 
 [[package]]
 name = "crossbeam-channel"
-version = "0.5.13"
+version = "0.5.14"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "33480d6946193aa8033910124896ca395333cae7e2d1113d1fef6c3272217df2"
+checksum = "06ba6d68e24814cb8de6bb986db8222d3a027d15872cabc0d18817bc3c0e4471"
 dependencies = [
  "crossbeam-utils",
 ]
 
 [[package]]
 name = "crossbeam-deque"
-version = "0.8.5"
+version = "0.8.6"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "613f8cc01fe9cf1a3eb3d7f488fd2fa8388403e97039e2f73692932e291a770d"
+checksum = "9dd111b7b7f7d55b72c0a6ae361660ee5853c9af73f70c3c2ef6858b950e2e51"
 dependencies = [
  "crossbeam-epoch",
  "crossbeam-utils",
@@ -1683,15 +1699,15 @@ dependencies = [
 
 [[package]]
 name = "crossbeam-utils"
-version = "0.8.20"
+version = "0.8.21"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "22ec99545bb0ed0ea7bb9b8e1e9122ea386ff8a48c0922e43f36d45ab09e0e80"
+checksum = "d0a5c400df2834b80a4c3327b3aad3a4c4cd4de0629063962b03235697506a28"
 
 [[package]]
 name = "crunchy"
-version = "0.2.2"
+version = "0.2.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "7a81dae078cea95a014a339291cec439d2f232ebe854a9d672b796c6afafa9b7"
+checksum = "43da5946c66ffcc7745f48db692ffbb10a83bfe0afd96235c5c2a4fb23994929"
 
 [[package]]
 name = "crypto-bigint"
@@ -1800,7 +1816,7 @@ checksum = "f46882e17999c6cc590af592290432be3bce0428cb0d5f8b6715e4dc7b383eb3"
 dependencies = [
  "proc-macro2",
  "quote",
- "syn 2.0.89",
+ "syn 2.0.96",
 ]
 
 [[package]]
@@ -1848,7 +1864,7 @@ dependencies = [
  "proc-macro2",
  "quote",
  "strsim 0.11.1",
- "syn 2.0.89",
+ "syn 2.0.96",
 ]
 
 [[package]]
@@ -1870,7 +1886,7 @@ checksum = "d336a2a514f6ccccaa3e09b02d41d35330c07ddf03a62165fcec10bb561c7806"
 dependencies = [
  "darling_core 0.20.10",
  "quote",
- "syn 2.0.89",
+ "syn 2.0.96",
 ]
 
 [[package]]
@@ -1901,15 +1917,15 @@ checksum = "04d2cd9c18b9f454ed67da600630b021a8a80bf33f8c95896ab33aaf1c26b728"
 
 [[package]]
 name = "data-encoding"
-version = "2.6.0"
+version = "2.7.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "e8566979429cf69b49a5c740c60791108e86440e8be149bbea4fe54d2c32d6e2"
+checksum = "0e60eed09d8c01d3cee5b7d30acb059b76614c918fa0f992e0dd6eeb10daad6f"
 
 [[package]]
 name = "data-encoding-macro"
-version = "0.1.15"
+version = "0.1.16"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "f1559b6cba622276d6d63706db152618eeb15b89b3e4041446b05876e352e639"
+checksum = "5b16d9d0d88a5273d830dac8b78ceb217ffc9b1d5404e5597a3542515329405b"
 dependencies = [
  "data-encoding",
  "data-encoding-macro-internal",
@@ -1917,12 +1933,12 @@ dependencies = [
 
 [[package]]
 name = "data-encoding-macro-internal"
-version = "0.1.13"
+version = "0.1.14"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "332d754c0af53bc87c108fed664d121ecf59207ec4196041f04d6ab9002ad33f"
+checksum = "1145d32e826a7748b69ee8fc62d3e6355ff7f1051df53141e7048162fc90481b"
 dependencies = [
  "data-encoding",
- "syn 1.0.109",
+ "syn 2.0.96",
 ]
 
 [[package]]
@@ -2036,7 +2052,7 @@ checksum = "30542c1ad912e0e3d22a1935c290e12e8a29d704a420177a31faad4a601a0800"
 dependencies = [
  "proc-macro2",
  "quote",
- "syn 2.0.89",
+ "syn 2.0.96",
 ]
 
 [[package]]
@@ -2049,7 +2065,7 @@ dependencies = [
  "proc-macro2",
  "quote",
  "rustc_version 0.4.1",
- "syn 2.0.89",
+ "syn 2.0.96",
 ]
 
 [[package]]
@@ -2069,17 +2085,17 @@ checksum = "cb7330aeadfbe296029522e6c40f315320aba36fc43a5b3632f3795348f3bd22"
 dependencies = [
  "proc-macro2",
  "quote",
- "syn 2.0.89",
+ "syn 2.0.96",
  "unicode-xid",
 ]
 
 [[package]]
 name = "diesel"
-version = "2.2.5"
+version = "2.2.6"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "cbf9649c05e0a9dbd6d0b0b8301db5182b972d0fd02f0a7c6736cf632d7c0fd5"
+checksum = "ccf1bedf64cdb9643204a36dd15b19a6ce8e7aa7f7b105868e9f1fad5ffa7d12"
 dependencies = [
- "bitflags 2.6.0",
+ "bitflags 2.8.0",
  "byteorder",
  "diesel_derives",
  "itoa",
@@ -2097,7 +2113,7 @@ dependencies = [
  "dsl_auto_type",
  "proc-macro2",
  "quote",
- "syn 2.0.89",
+ "syn 2.0.96",
 ]
 
 [[package]]
@@ -2117,7 +2133,7 @@ version = "0.2.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "209c735641a413bc68c4923a9d6ad4bcb3ca306b794edaa7eb0b3228a99ffb25"
 dependencies = [
- "syn 2.0.89",
+ "syn 2.0.96",
 ]
 
 [[package]]
@@ -2193,9 +2209,9 @@ dependencies = [
 
 [[package]]
 name = "discv5"
-version = "0.9.0"
+version = "0.9.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "898d136ecb64116ec68aecf14d889bd30f8b1fe0c19e262953f7388dbe77052e"
+checksum = "c4b4e7798d2ff74e29cee344dc490af947ae657d6ab5273dde35d58ce06a4d71"
 dependencies = [
  "aes 0.8.4",
  "aes-gcm",
@@ -2232,7 +2248,7 @@ checksum = "97369cbbc041bc366949bc74d34658d6cda5621039731c6310521892a3a20ae0"
 dependencies = [
  "proc-macro2",
  "quote",
- "syn 2.0.89",
+ "syn 2.0.96",
 ]
 
 [[package]]
@@ -2263,7 +2279,7 @@ dependencies = [
  "heck 0.5.0",
  "proc-macro2",
  "quote",
- "syn 2.0.89",
+ "syn 2.0.96",
 ]
 
 [[package]]
@@ -2443,7 +2459,7 @@ dependencies = [
  "heck 0.5.0",
  "proc-macro2",
  "quote",
- "syn 2.0.89",
+ "syn 2.0.96",
 ]
 
 [[package]]
@@ -2507,12 +2523,12 @@ dependencies = [
 
 [[package]]
 name = "errno"
-version = "0.3.9"
+version = "0.3.10"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "534c5cf6194dfab3db3242765c03bbe257cf92f22b38f6bc0c58d59108a820ba"
+checksum = "33d852cb9b869c2a9b3df2f71a3074817f01e1844f839a144f5fcef059a4eb5d"
 dependencies = [
  "libc",
- "windows-sys 0.52.0",
+ "windows-sys 0.59.0",
 ]
 
 [[package]]
@@ -2563,6 +2579,7 @@ name = "eth2"
 version = "0.1.0"
 dependencies = [
  "derivative",
+ "either",
  "eth2_keystore",
  "ethereum_serde_utils",
  "ethereum_ssz",
@@ -2572,9 +2589,7 @@ dependencies = [
  "lighthouse_network",
  "mediatype",
  "pretty_reqwest_error",
- "procfs",
  "proto_array",
- "psutil",
  "reqwest",
  "reqwest-eventsource",
  "sensitive_url",
@@ -2639,7 +2654,7 @@ dependencies = [
  "sha2 0.9.9",
  "tempfile",
  "unicode-normalization",
- "uuid",
+ "uuid 0.8.2",
  "zeroize",
 ]
 
@@ -2679,7 +2694,7 @@ dependencies = [
  "serde_repr",
  "tempfile",
  "tiny-bip39",
- "uuid",
+ "uuid 0.8.2",
 ]
 
 [[package]]
@@ -2825,7 +2840,7 @@ dependencies = [
  "darling 0.20.10",
  "proc-macro2",
  "quote",
- "syn 2.0.89",
+ "syn 2.0.96",
 ]
 
 [[package]]
@@ -2858,7 +2873,7 @@ dependencies = [
  "dunce",
  "ethers-core",
  "eyre",
- "getrandom",
+ "getrandom 0.2.15",
  "hex",
  "proc-macro2",
  "quote",
@@ -2929,7 +2944,7 @@ dependencies = [
  "futures-core",
  "futures-timer",
  "futures-util",
- "getrandom",
+ "getrandom 0.2.15",
  "hashers",
  "hex",
  "http 0.2.12",
@@ -2959,9 +2974,9 @@ checksum = "0206175f82b8d6bf6652ff7d71a1e27fd2e4efde587fd368662814d6ec1d9ce0"
 
 [[package]]
 name = "event-listener"
-version = "5.3.1"
+version = "5.4.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "6032be9bd27023a771701cc49f9f053c751055f71efb2e0ae5c15809093675ba"
+checksum = "3492acde4c3fc54c845eaab3eed8bd00c7a7d881f78bfc801e43a93dec1331ae"
 dependencies = [
  "concurrent-queue",
  "parking",
@@ -2970,11 +2985,11 @@ dependencies = [
 
 [[package]]
 name = "event-listener-strategy"
-version = "0.5.2"
+version = "0.5.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "0f214dc438f977e6d4e3500aaa277f5ad94ca83fbbd9b1a15713ce2344ccc5a1"
+checksum = "3c3e4e0dd3673c1139bf041f3008816d9cf2946bbfac2945c09e523b8d7b05b2"
 dependencies = [
- "event-listener 5.3.1",
+ "event-listener 5.4.0",
  "pin-project-lite",
 ]
 
@@ -3089,9 +3104,9 @@ checksum = "7360491ce676a36bf9bb3c56c1aa791658183a54d2744120f27285738d90465a"
 
 [[package]]
 name = "fastrand"
-version = "2.2.0"
+version = "2.3.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "486f806e73c5707928240ddc295403b1b93c96a02038563881c4a2fd84b81ac4"
+checksum = "37909eebbb50d72f9059c3b6d82c0463f2ff062c9e95845c43a6c9c0355411be"
 
 [[package]]
 name = "fastrlp"
@@ -3104,6 +3119,17 @@ dependencies = [
  "bytes",
 ]
 
+[[package]]
+name = "fastrlp"
+version = "0.4.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "ce8dba4714ef14b8274c371879b175aa55b16b30f269663f19d576f380018dc4"
+dependencies = [
+ "arrayvec",
+ "auto_impl",
+ "bytes",
+]
+
 [[package]]
 name = "fdlimit"
 version = "0.3.0"
@@ -3216,9 +3242,9 @@ checksum = "3f9eec918d3f24069decb9af1554cad7c880e2da24a9afd88aca000531ab82c1"
 
 [[package]]
 name = "foldhash"
-version = "0.1.3"
+version = "0.1.4"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "f81ec6369c545a7d40e4589b5597581fa1c441fe1cce96dd1de43159910a36a2"
+checksum = "a0d2fde1f7b3d48b8395d5f2de76c18a528bd6a9cdde438df747bfcba3e05d6f"
 
 [[package]]
 name = "foreign-types"
@@ -3343,9 +3369,9 @@ checksum = "9e5c1b78ca4aae1ac06c48a526a655760685149f0d465d21f37abfe57ce075c6"
 
 [[package]]
 name = "futures-lite"
-version = "2.5.0"
+version = "2.6.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "cef40d21ae2c515b51041df9ed313ed21e572df340ea58a922a0aefe7e8891a1"
+checksum = "f5edaec856126859abb19ed65f39e90fea3a9574b9707f13539acf4abf7eb532"
 dependencies = [
  "futures-core",
  "pin-project-lite",
@@ -3359,7 +3385,7 @@ checksum = "162ee34ebcb7c64a8abebc059ce0fee27c2262618d7b60ed8faf72fef13c3650"
 dependencies = [
  "proc-macro2",
  "quote",
- "syn 2.0.89",
+ "syn 2.0.96",
 ]
 
 [[package]]
@@ -3369,7 +3395,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "a8f2f12607f92c69b12ed746fabf9ca4f5c482cba46679c1a75b874ed7c26adb"
 dependencies = [
  "futures-io",
- "rustls 0.23.18",
+ "rustls 0.23.21",
  "rustls-pki-types",
 ]
 
@@ -3422,6 +3448,19 @@ dependencies = [
  "byteorder",
 ]
 
+[[package]]
+name = "generator"
+version = "0.8.4"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "cc6bd114ceda131d3b1d665eba35788690ad37f5916457286b32ab6fd3c438dd"
+dependencies = [
+ "cfg-if",
+ "libc",
+ "log",
+ "rustversion",
+ "windows 0.58.0",
+]
+
 [[package]]
 name = "generic-array"
 version = "0.14.7"
@@ -3463,10 +3502,22 @@ dependencies = [
  "cfg-if",
  "js-sys",
  "libc",
- "wasi",
+ "wasi 0.11.0+wasi-snapshot-preview1",
  "wasm-bindgen",
 ]
 
+[[package]]
+name = "getrandom"
+version = "0.3.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "43a49c392881ce6d5c3b8cb70f98717b7c07aabbdff06687b9030dbfbe2725f8"
+dependencies = [
+ "cfg-if",
+ "libc",
+ "wasi 0.13.3+wasi-0.2.2",
+ "windows-targets 0.52.6",
+]
+
 [[package]]
 name = "ghash"
 version = "0.5.1"
@@ -3500,14 +3551,14 @@ checksum = "53010ccb100b96a67bc32c0175f0ed1426b31b655d562898e57325f81c023ac0"
 dependencies = [
  "proc-macro2",
  "quote",
- "syn 2.0.89",
+ "syn 2.0.96",
 ]
 
 [[package]]
 name = "glob"
-version = "0.3.1"
+version = "0.3.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "d2fabcfbdc87f4758337ca535fb41a6d701b65693ce38287d856d1674551ec9b"
+checksum = "a8d1add55171497b4705a648c6b583acafb01d58050a51727785f0b2c8e0a2b2"
 
 [[package]]
 name = "gloo-timers"
@@ -3534,7 +3585,7 @@ dependencies = [
  "fnv",
  "futures",
  "futures-timer",
- "getrandom",
+ "getrandom 0.2.15",
  "hashlink 0.9.1",
  "hex_fmt",
  "libp2p",
@@ -3599,7 +3650,26 @@ dependencies = [
  "futures-sink",
  "futures-util",
  "http 0.2.12",
- "indexmap 2.6.0",
+ "indexmap 2.7.1",
+ "slab",
+ "tokio",
+ "tokio-util",
+ "tracing",
+]
+
+[[package]]
+name = "h2"
+version = "0.4.7"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "ccae279728d634d083c00f6099cb58f01cc99c145b84b8be2f6c74618d79922e"
+dependencies = [
+ "atomic-waker",
+ "bytes",
+ "fnv",
+ "futures-core",
+ "futures-sink",
+ "http 1.2.0",
+ "indexmap 2.7.1",
  "slab",
  "tokio",
  "tokio-util",
@@ -3649,9 +3719,9 @@ dependencies = [
 
 [[package]]
 name = "hashbrown"
-version = "0.15.1"
+version = "0.15.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "3a9bfc1af68b1726ea47d3d5109de126281def866b33970e10fbab11b5dafab3"
+checksum = "bf151400ff0baff5465007dd2f3e717f3fe502074ca563069ce3a6629d07b289"
 dependencies = [
  "allocator-api2",
  "equivalent",
@@ -3710,6 +3780,16 @@ dependencies = [
  "http 0.2.12",
 ]
 
+[[package]]
+name = "health_metrics"
+version = "0.1.0"
+dependencies = [
+ "eth2",
+ "metrics",
+ "procfs",
+ "psutil",
+]
+
 [[package]]
 name = "heck"
 version = "0.4.1"
@@ -3752,12 +3832,6 @@ dependencies = [
  "serde",
 ]
 
-[[package]]
-name = "hex-literal"
-version = "0.4.1"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "6fe2267d4ed49bc07b63801559be28c718ea06c4738b7a03c94df7386d2cde46"
-
 [[package]]
 name = "hex_fmt"
 version = "0.3.0"
@@ -3766,10 +3840,11 @@ checksum = "b07f60793ff0a4d9cef0f18e63b5357e06209987153a64648c972c1e5aff336f"
 
 [[package]]
 name = "hickory-proto"
-version = "0.24.1"
+version = "0.25.0-alpha.4"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "07698b8420e2f0d6447a436ba999ec85d8fbf2a398bbd737b82cac4a2e96e512"
+checksum = "d063c0692ee669aa6d261988aa19ca5510f1cc40e4f211024f50c888499a35d7"
 dependencies = [
+ "async-recursion",
  "async-trait",
  "cfg-if",
  "data-encoding",
@@ -3777,12 +3852,12 @@ dependencies = [
  "futures-channel",
  "futures-io",
  "futures-util",
- "idna 0.4.0",
+ "idna",
  "ipnet",
  "once_cell",
  "rand",
  "socket2",
- "thiserror 1.0.69",
+ "thiserror 2.0.11",
  "tinyvec",
  "tokio",
  "tracing",
@@ -3791,21 +3866,21 @@ dependencies = [
 
 [[package]]
 name = "hickory-resolver"
-version = "0.24.1"
+version = "0.25.0-alpha.4"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "28757f23aa75c98f254cf0405e6d8c25b831b32921b050a66692427679b1f243"
+checksum = "42bc352e4412fb657e795f79b4efcf2bd60b59ee5ca0187f3554194cd1107a27"
 dependencies = [
  "cfg-if",
  "futures-util",
  "hickory-proto",
  "ipconfig",
- "lru-cache",
+ "moka",
  "once_cell",
  "parking_lot 0.12.3",
  "rand",
  "resolv-conf",
  "smallvec",
- "thiserror 1.0.69",
+ "thiserror 2.0.11",
  "tokio",
  "tracing",
 ]
@@ -3861,11 +3936,11 @@ dependencies = [
 
 [[package]]
 name = "home"
-version = "0.5.9"
+version = "0.5.11"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "e3d1354bf6b7235cb4a0576c2619fd4ed18183f689b12b006a0ee7329eeff9a5"
+checksum = "589533453244b0995c858700322199b2becb13b627df2851f64a2775d024abcf"
 dependencies = [
- "windows-sys 0.52.0",
+ "windows-sys 0.59.0",
 ]
 
 [[package]]
@@ -3892,9 +3967,9 @@ dependencies = [
 
 [[package]]
 name = "http"
-version = "1.1.0"
+version = "1.2.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "21b9ddb458710bc376481b842f5da65cdf31522de232c1ca8146abce2a358258"
+checksum = "f16ca2af56261c99fba8bac40a10251ce8188205a4c448fbb745a2e4daa76fea"
 dependencies = [
  "bytes",
  "fnv",
@@ -3919,7 +3994,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "1efedce1fb8e6913f23e0c92de8e62cd5b772a67e7b3946df930a62566c93184"
 dependencies = [
  "bytes",
- "http 1.1.0",
+ "http 1.2.0",
 ]
 
 [[package]]
@@ -3930,7 +4005,7 @@ checksum = "793429d76616a256bcb62c2a2ec2bed781c8307e797e2598c50010f2bee2544f"
 dependencies = [
  "bytes",
  "futures-util",
- "http 1.1.0",
+ "http 1.2.0",
  "http-body 1.0.1",
  "pin-project-lite",
 ]
@@ -3944,6 +4019,7 @@ dependencies = [
  "bs58 0.4.0",
  "bytes",
  "directory",
+ "either",
  "eth1",
  "eth2",
  "ethereum_serde_utils",
@@ -3951,6 +4027,7 @@ dependencies = [
  "execution_layer",
  "futures",
  "genesis",
+ "health_metrics",
  "hex",
  "lighthouse_network",
  "lighthouse_version",
@@ -3986,6 +4063,7 @@ name = "http_metrics"
 version = "0.1.0"
 dependencies = [
  "beacon_chain",
+ "health_metrics",
  "lighthouse_network",
  "lighthouse_version",
  "logging",
@@ -4004,9 +4082,9 @@ dependencies = [
 
 [[package]]
 name = "httparse"
-version = "1.9.5"
+version = "1.10.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "7d71d3574edd2771538b901e6549113b4006ece66150fb69c0fb6d9a2adae946"
+checksum = "f2d708df4e7140240a16cd6ab0ab65c972d7433ab77819ea693fde9c43811e2a"
 
 [[package]]
 name = "httpdate"
@@ -4022,15 +4100,15 @@ checksum = "9a3a5bfb195931eeb336b2a7b4d761daec841b97f947d34394601737a7bba5e4"
 
 [[package]]
 name = "hyper"
-version = "0.14.31"
+version = "0.14.32"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "8c08302e8fa335b151b788c775ff56e7a03ae64ff85c548ee820fecb70356e85"
+checksum = "41dfc780fdec9373c01bae43289ea34c972e40ee3c9f6b3c8801a35f35586ce7"
 dependencies = [
  "bytes",
  "futures-channel",
  "futures-core",
  "futures-util",
- "h2",
+ "h2 0.3.26",
  "http 0.2.12",
  "http-body 0.4.6",
  "httparse",
@@ -4046,14 +4124,15 @@ dependencies = [
 
 [[package]]
 name = "hyper"
-version = "1.5.1"
+version = "1.6.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "97818827ef4f364230e16705d4706e2897df2bb60617d6ca15d598025a3c481f"
+checksum = "cc2b571658e38e0c01b1fdca3bbbe93c00d3d71693ff2770043f8c29bc7d6f80"
 dependencies = [
  "bytes",
  "futures-channel",
  "futures-util",
- "http 1.1.0",
+ "h2 0.4.7",
+ "http 1.2.0",
  "http-body 1.0.1",
  "httparse",
  "httpdate",
@@ -4061,6 +4140,7 @@ dependencies = [
  "pin-project-lite",
  "smallvec",
  "tokio",
+ "want",
 ]
 
 [[package]]
@@ -4071,7 +4151,7 @@ checksum = "ec3efd23720e2049821a693cbc7e65ea87c72f1c58ff2f9522ff332b1491e590"
 dependencies = [
  "futures-util",
  "http 0.2.12",
- "hyper 0.14.31",
+ "hyper 0.14.32",
  "rustls 0.21.12",
  "tokio",
  "tokio-rustls 0.24.1",
@@ -4084,7 +4164,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "d6183ddfa99b85da61a140bea0efc93fdf56ceaa041b37d553518030827f9905"
 dependencies = [
  "bytes",
- "hyper 0.14.31",
+ "hyper 0.14.32",
  "native-tls",
  "tokio",
  "tokio-native-tls",
@@ -4097,13 +4177,16 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "df2dcfbe0677734ab2f3ffa7fa7bfd4706bfdc1ef393f2ee30184aed67e631b4"
 dependencies = [
  "bytes",
+ "futures-channel",
  "futures-util",
- "http 1.1.0",
+ "http 1.2.0",
  "http-body 1.0.1",
- "hyper 1.5.1",
+ "hyper 1.6.0",
  "pin-project-lite",
+ "socket2",
  "tokio",
  "tower-service",
+ "tracing",
 ]
 
 [[package]]
@@ -4244,7 +4327,7 @@ checksum = "1ec89e9337638ecdc08744df490b221a7399bf8d164eb52a665454e60e075ad6"
 dependencies = [
  "proc-macro2",
  "quote",
- "syn 2.0.89",
+ "syn 2.0.96",
 ]
 
 [[package]]
@@ -4253,16 +4336,6 @@ version = "1.0.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "b9e0384b61958566e926dc50660321d12159025e767c18e043daf26b70104c39"
 
-[[package]]
-name = "idna"
-version = "0.4.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "7d20d6b07bfbc108882d88ed8e37d39636dcc260e15e30c45e6ba089610b917c"
-dependencies = [
- "unicode-bidi",
- "unicode-normalization",
-]
-
 [[package]]
 name = "idna"
 version = "1.0.3"
@@ -4314,21 +4387,44 @@ dependencies = [
  "rtnetlink",
  "system-configuration 0.6.1",
  "tokio",
- "windows",
+ "windows 0.53.0",
 ]
 
 [[package]]
 name = "igd-next"
-version = "0.14.3"
+version = "0.15.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "064d90fec10d541084e7b39ead8875a5a80d9114a2b18791565253bae25f49e4"
+checksum = "76b0d7d4541def58a37bf8efc559683f21edce7c82f0d866c93ac21f7e098f93"
 dependencies = [
  "async-trait",
  "attohttpc",
  "bytes",
  "futures",
- "http 0.2.12",
- "hyper 0.14.31",
+ "http 1.2.0",
+ "http-body-util",
+ "hyper 1.6.0",
+ "hyper-util",
+ "log",
+ "rand",
+ "tokio",
+ "url",
+ "xmltree",
+]
+
+[[package]]
+name = "igd-next"
+version = "0.16.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "2830127baaaa55dae9aa5ee03158d5aa3687a9c2c11ce66870452580cc695df4"
+dependencies = [
+ "async-trait",
+ "attohttpc",
+ "bytes",
+ "futures",
+ "http 1.2.0",
+ "http-body-util",
+ "hyper 1.6.0",
+ "hyper-util",
  "log",
  "rand",
  "tokio",
@@ -4351,7 +4447,7 @@ version = "0.6.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "ba6a270039626615617f3f36d15fc827041df3b78c439da2cadfa47455a77f2f"
 dependencies = [
- "parity-scale-codec 3.7.0",
+ "parity-scale-codec 3.6.12",
 ]
 
 [[package]]
@@ -4389,7 +4485,7 @@ checksum = "a0eb5a3343abf848c0984fe4604b2b105da9539376e24fc0a3b0007411ae4fd9"
 dependencies = [
  "proc-macro2",
  "quote",
- "syn 2.0.89",
+ "syn 2.0.96",
 ]
 
 [[package]]
@@ -4410,13 +4506,13 @@ dependencies = [
 
 [[package]]
 name = "indexmap"
-version = "2.6.0"
+version = "2.7.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "707907fe3c25f5424cce2cb7e1cbcafee6bdbe735ca90ef77c29e84591e5b9da"
+checksum = "8c9c992b02b5b4c94ea26e32fe5bccb7aa7d9f390ab5c1221ff895bc7ea8b652"
 dependencies = [
  "arbitrary",
  "equivalent",
- "hashbrown 0.15.1",
+ "hashbrown 0.15.2",
  "serde",
 ]
 
@@ -4510,19 +4606,19 @@ dependencies = [
 
 [[package]]
 name = "ipnet"
-version = "2.10.1"
+version = "2.11.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "ddc24109865250148c2e0f3d25d4f0f479571723792d3802153c60922a4fb708"
+checksum = "469fb0b9cefa57e3ef31275ee7cacb78f2fdca44e4765491884a2b119d4eb130"
 
 [[package]]
 name = "is-terminal"
-version = "0.4.13"
+version = "0.4.15"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "261f68e344040fbd0edea105bef17c66edf46f984ddb1115b775ce31be948f4b"
+checksum = "e19b23d53f35ce9f56aebc7d1bb4e6ac1e9c0db7ac85c8d1760c04379edced37"
 dependencies = [
  "hermit-abi 0.4.0",
  "libc",
- "windows-sys 0.52.0",
+ "windows-sys 0.59.0",
 ]
 
 [[package]]
@@ -4560,9 +4656,9 @@ dependencies = [
 
 [[package]]
 name = "itoa"
-version = "1.0.13"
+version = "1.0.14"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "540654e97a3f4470a492cd30ff187bc95d89557a903a2bbf112e2fae98104ef2"
+checksum = "d75a2a4b1b190afb6f5425f10f6a8f959d2ea0b9c2b1d79553551850539e4674"
 
 [[package]]
 name = "jobserver"
@@ -4575,10 +4671,11 @@ dependencies = [
 
 [[package]]
 name = "js-sys"
-version = "0.3.72"
+version = "0.3.77"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "6a88f1bda2bd75b0452a14784937d796722fdebfe50df998aeb3f0b7603019a9"
+checksum = "1cfaf33c695fc6e08064efbc1f72ec937429614f25eef83af942d0e227c3a28f"
 dependencies = [
+ "once_cell",
  "wasm-bindgen",
 ]
 
@@ -4659,6 +4756,11 @@ version = "0.1.0"
 dependencies = [
  "arbitrary",
  "c-kzg",
+ "crate_crypto_internal_eth_kzg_bls12_381",
+ "crate_crypto_internal_eth_kzg_erasure_codes",
+ "crate_crypto_internal_eth_kzg_maybe_rayon",
+ "crate_crypto_internal_eth_kzg_polynomial",
+ "crate_crypto_kzg_multi_open_fk20",
  "criterion",
  "derivative",
  "ethereum_hashing",
@@ -4748,9 +4850,9 @@ dependencies = [
 
 [[package]]
 name = "libc"
-version = "0.2.164"
+version = "0.2.169"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "433bfe06b8c75da9b2e3fbea6e5329ff87748f0b144ef75306e674c3f6f7c13f"
+checksum = "b5aba8db14291edd000dfcc4d620c7ebfb122c613afb886ca8803fa4e128a20a"
 
 [[package]]
 name = "libflate"
@@ -4778,9 +4880,9 @@ dependencies = [
 
 [[package]]
 name = "libloading"
-version = "0.8.5"
+version = "0.8.6"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "4979f22fdb869068da03c9f7528f8297c6fd2606bc3a4affe42e6a823fdb8da4"
+checksum = "fc2f4eb4bc735547cfed7c0a4922cbd04a4655978c09b54f1f7b228750664c34"
 dependencies = [
  "cfg-if",
  "windows-targets 0.52.6",
@@ -4809,15 +4911,15 @@ dependencies = [
 
 [[package]]
 name = "libp2p"
-version = "0.54.1"
+version = "0.55.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "bbbe80f9c7e00526cd6b838075b9c171919404a4732cb2fa8ece0a093223bfc4"
+checksum = "b72dc443ddd0254cb49a794ed6b6728400ee446a0f7ab4a07d0209ee98de20e9"
 dependencies = [
  "bytes",
  "either",
  "futures",
  "futures-timer",
- "getrandom",
+ "getrandom 0.2.15",
  "libp2p-allow-block-list",
  "libp2p-connection-limits",
  "libp2p-core",
@@ -4836,38 +4938,36 @@ dependencies = [
  "multiaddr",
  "pin-project",
  "rw-stream-sink",
- "thiserror 1.0.69",
+ "thiserror 2.0.11",
 ]
 
 [[package]]
 name = "libp2p-allow-block-list"
-version = "0.4.0"
+version = "0.5.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "d1027ccf8d70320ed77e984f273bc8ce952f623762cb9bf2d126df73caef8041"
+checksum = "38944b7cb981cc93f2f0fb411ff82d0e983bd226fbcc8d559639a3a73236568b"
 dependencies = [
  "libp2p-core",
  "libp2p-identity",
  "libp2p-swarm",
- "void",
 ]
 
 [[package]]
 name = "libp2p-connection-limits"
-version = "0.4.0"
+version = "0.5.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "8d003540ee8baef0d254f7b6bfd79bac3ddf774662ca0abf69186d517ef82ad8"
+checksum = "efe9323175a17caa8a2ed4feaf8a548eeef5e0b72d03840a0eab4bcb0210ce1c"
 dependencies = [
  "libp2p-core",
  "libp2p-identity",
  "libp2p-swarm",
- "void",
 ]
 
 [[package]]
 name = "libp2p-core"
-version = "0.42.0"
+version = "0.43.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "a61f26c83ed111104cd820fe9bc3aaabbac5f1652a1d213ed6e900b7918a1298"
+checksum = "193c75710ba43f7504ad8f58a62ca0615b1d7e572cb0f1780bc607252c39e9ef"
 dependencies = [
  "either",
  "fnv",
@@ -4883,19 +4983,17 @@ dependencies = [
  "quick-protobuf",
  "rand",
  "rw-stream-sink",
- "smallvec",
- "thiserror 1.0.69",
+ "thiserror 2.0.11",
  "tracing",
  "unsigned-varint 0.8.0",
- "void",
  "web-time",
 ]
 
 [[package]]
 name = "libp2p-dns"
-version = "0.42.0"
+version = "0.43.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "97f37f30d5c7275db282ecd86e54f29dd2176bd3ac656f06abf43bedb21eb8bd"
+checksum = "1b780a1150214155b0ed1cdf09fbd2e1b0442604f9146a431d1b21d23eef7bd7"
 dependencies = [
  "async-trait",
  "futures",
@@ -4909,9 +5007,9 @@ dependencies = [
 
 [[package]]
 name = "libp2p-identify"
-version = "0.45.0"
+version = "0.46.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "1711b004a273be4f30202778856368683bd9a83c4c7dcc8f848847606831a4e3"
+checksum = "e8c06862544f02d05d62780ff590cc25a75f5c2b9df38ec7a370dcae8bb873cf"
 dependencies = [
  "asynchronous-codec",
  "either",
@@ -4921,13 +5019,11 @@ dependencies = [
  "libp2p-core",
  "libp2p-identity",
  "libp2p-swarm",
- "lru",
  "quick-protobuf",
  "quick-protobuf-codec",
  "smallvec",
- "thiserror 1.0.69",
+ "thiserror 2.0.11",
  "tracing",
- "void",
 ]
 
 [[package]]
@@ -4954,11 +5050,10 @@ dependencies = [
 
 [[package]]
 name = "libp2p-mdns"
-version = "0.46.0"
+version = "0.47.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "14b8546b6644032565eb29046b42744aee1e9f261ed99671b2c93fb140dba417"
+checksum = "11d0ba095e1175d797540e16b62e7576846b883cb5046d4159086837b36846cc"
 dependencies = [
- "data-encoding",
  "futures",
  "hickory-proto",
  "if-watch",
@@ -4970,14 +5065,13 @@ dependencies = [
  "socket2",
  "tokio",
  "tracing",
- "void",
 ]
 
 [[package]]
 name = "libp2p-metrics"
-version = "0.15.0"
+version = "0.16.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "77ebafa94a717c8442d8db8d3ae5d1c6a15e30f2d347e0cd31d057ca72e42566"
+checksum = "2ce58c64292e87af624fcb86465e7dd8342e46a388d71e8fec0ab37ee789630a"
 dependencies = [
  "futures",
  "libp2p-core",
@@ -4991,9 +5085,9 @@ dependencies = [
 
 [[package]]
 name = "libp2p-mplex"
-version = "0.42.0"
+version = "0.43.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "41187ab8f6c835ad864edf94224f666f636ee2d270601422c1441f739e0abccc"
+checksum = "8aaa6fee3722e355443058472fc4705d78681bc2d8e447a0bdeb3fecf40cd197"
 dependencies = [
  "asynchronous-codec",
  "bytes",
@@ -5010,13 +5104,12 @@ dependencies = [
 
 [[package]]
 name = "libp2p-noise"
-version = "0.45.0"
+version = "0.46.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "36b137cb1ae86ee39f8e5d6245a296518912014eaa87427d24e6ff58cfc1b28c"
+checksum = "afcc133e0f3cea07acde6eb8a9665cb11b600bd61110b010593a0210b8153b16"
 dependencies = [
  "asynchronous-codec",
  "bytes",
- "curve25519-dalek",
  "futures",
  "libp2p-core",
  "libp2p-identity",
@@ -5025,10 +5118,9 @@ dependencies = [
  "once_cell",
  "quick-protobuf",
  "rand",
- "sha2 0.10.8",
  "snow",
  "static_assertions",
- "thiserror 1.0.69",
+ "thiserror 2.0.11",
  "tracing",
  "x25519-dalek",
  "zeroize",
@@ -5036,9 +5128,9 @@ dependencies = [
 
 [[package]]
 name = "libp2p-plaintext"
-version = "0.42.0"
+version = "0.43.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "5b63d926c6be56a2489e0e7316b17fe95a70bc5c4f3e85740bb3e67c0f3c6a44"
+checksum = "7e659439578fc6d305da8303834beb9d62f155f40e7f5b9d81c9f2b2c69d1926"
 dependencies = [
  "asynchronous-codec",
  "bytes",
@@ -5052,33 +5144,31 @@ dependencies = [
 
 [[package]]
 name = "libp2p-quic"
-version = "0.11.1"
+version = "0.12.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "46352ac5cd040c70e88e7ff8257a2ae2f891a4076abad2c439584a31c15fd24e"
+checksum = "41432a159b00424a0abaa2c80d786cddff81055ac24aa127e0cf375f7858d880"
 dependencies = [
- "bytes",
  "futures",
  "futures-timer",
  "if-watch",
  "libp2p-core",
  "libp2p-identity",
  "libp2p-tls",
- "parking_lot 0.12.3",
  "quinn",
  "rand",
  "ring 0.17.8",
- "rustls 0.23.18",
+ "rustls 0.23.21",
  "socket2",
- "thiserror 1.0.69",
+ "thiserror 2.0.11",
  "tokio",
  "tracing",
 ]
 
 [[package]]
 name = "libp2p-swarm"
-version = "0.45.1"
+version = "0.46.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "d7dd6741793d2c1fb2088f67f82cf07261f25272ebe3c0b0c311e0c6b50e851a"
+checksum = "803399b4b6f68adb85e63ab573ac568154b193e9a640f03e0f2890eabbcb37f8"
 dependencies = [
  "either",
  "fnv",
@@ -5094,7 +5184,6 @@ dependencies = [
  "smallvec",
  "tokio",
  "tracing",
- "void",
  "web-time",
 ]
 
@@ -5107,21 +5196,20 @@ dependencies = [
  "heck 0.5.0",
  "proc-macro2",
  "quote",
- "syn 2.0.89",
+ "syn 2.0.96",
 ]
 
 [[package]]
 name = "libp2p-tcp"
-version = "0.42.0"
+version = "0.43.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "ad964f312c59dcfcac840acd8c555de8403e295d39edf96f5240048b5fcaa314"
+checksum = "65346fb4d36035b23fec4e7be4c320436ba53537ce9b6be1d1db1f70c905cad0"
 dependencies = [
  "futures",
  "futures-timer",
  "if-watch",
  "libc",
  "libp2p-core",
- "libp2p-identity",
  "socket2",
  "tokio",
  "tracing",
@@ -5129,9 +5217,9 @@ dependencies = [
 
 [[package]]
 name = "libp2p-tls"
-version = "0.5.0"
+version = "0.6.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "47b23dddc2b9c355f73c1e36eb0c3ae86f7dc964a3715f0731cfad352db4d847"
+checksum = "dcaebc1069dea12c5b86a597eaaddae0317c2c2cb9ec99dc94f82fd340f5c78b"
 dependencies = [
  "futures",
  "futures-rustls",
@@ -5139,39 +5227,38 @@ dependencies = [
  "libp2p-identity",
  "rcgen",
  "ring 0.17.8",
- "rustls 0.23.18",
+ "rustls 0.23.21",
  "rustls-webpki 0.101.7",
- "thiserror 1.0.69",
+ "thiserror 2.0.11",
  "x509-parser",
  "yasna",
 ]
 
 [[package]]
 name = "libp2p-upnp"
-version = "0.3.0"
+version = "0.4.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "01bf2d1b772bd3abca049214a3304615e6a36fa6ffc742bdd1ba774486200b8f"
+checksum = "d457b9ecceb66e7199f049926fad447f1f17f040e8d29d690c086b4cab8ed14a"
 dependencies = [
  "futures",
  "futures-timer",
- "igd-next",
+ "igd-next 0.15.1",
  "libp2p-core",
  "libp2p-swarm",
  "tokio",
  "tracing",
- "void",
 ]
 
 [[package]]
 name = "libp2p-yamux"
-version = "0.46.0"
+version = "0.47.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "788b61c80789dba9760d8c669a5bedb642c8267555c803fabd8396e4ca5c5882"
+checksum = "f15df094914eb4af272acf9adaa9e287baa269943f32ea348ba29cfb9bfc60d8"
 dependencies = [
  "either",
  "futures",
  "libp2p-core",
- "thiserror 1.0.69",
+ "thiserror 2.0.11",
  "tracing",
  "yamux 0.12.1",
  "yamux 0.13.4",
@@ -5183,7 +5270,7 @@ version = "0.1.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "c0ff37bd590ca25063e35af745c343cb7a0271906fb7b37e4813e8f79f00268d"
 dependencies = [
- "bitflags 2.6.0",
+ "bitflags 2.8.0",
  "libc",
 ]
 
@@ -5248,9 +5335,9 @@ dependencies = [
 
 [[package]]
 name = "libz-sys"
-version = "1.1.20"
+version = "1.1.21"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "d2d16453e800a8cf6dd2fc3eb4bc99b786a9b90c663b8559a5b1a041bf89e472"
+checksum = "df9b68e50e6e0b26f672573834882eb57759f6db9b3be2ea3c35c91188bb4eaa"
 dependencies = [
  "cc",
  "pkg-config",
@@ -5291,6 +5378,7 @@ dependencies = [
  "slasher",
  "slashing_protection",
  "slog",
+ "store",
  "task_executor",
  "tempfile",
  "types",
@@ -5365,12 +5453,6 @@ dependencies = [
  "target_info",
 ]
 
-[[package]]
-name = "linked-hash-map"
-version = "0.5.6"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "0717cef1bc8b636c6e1c1bbdefc09e6322da8a9321966e8928ef80d20f7f770f"
-
 [[package]]
 name = "linux-raw-sys"
 version = "0.1.4"
@@ -5379,9 +5461,9 @@ checksum = "f051f77a7c8e6957c0696eac88f26b0117e54f52d3fc682ab19397a8812846a4"
 
 [[package]]
 name = "linux-raw-sys"
-version = "0.4.14"
+version = "0.4.15"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "78b3ae25bc7c8c38cec158d1f2757ee79e9b3740fbc7ccf0e59e4b08d793fa89"
+checksum = "d26c52dbd32dccf2d10cac7725f8eae5296885fb5703b261f7d0a0739ec807ab"
 
 [[package]]
 name = "litemap"
@@ -5430,9 +5512,9 @@ dependencies = [
 
 [[package]]
 name = "log"
-version = "0.4.22"
+version = "0.4.25"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "a7a70ba024b9dc04c27ea2f0c0548feb474ec5c54bba33a7f72f873a39d07b24"
+checksum = "04cbf5b083de1c7e0222a7a51dbfdba1cbe1c6ab0b15e29fff3f6c077fd9cd9f"
 
 [[package]]
 name = "logging"
@@ -5455,22 +5537,26 @@ dependencies = [
  "tracing-subscriber",
 ]
 
+[[package]]
+name = "loom"
+version = "0.7.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "419e0dc8046cb947daa77eb95ae174acfbddb7673b4151f56d1eed8e93fbfaca"
+dependencies = [
+ "cfg-if",
+ "generator",
+ "scoped-tls",
+ "tracing",
+ "tracing-subscriber",
+]
+
 [[package]]
 name = "lru"
 version = "0.12.5"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "234cf4f4a04dc1f57e24b96cc0cd600cf2af460d4161ac5ecdd0af8e1f3b2a38"
 dependencies = [
- "hashbrown 0.15.1",
-]
-
-[[package]]
-name = "lru-cache"
-version = "0.1.2"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "31e24f1ad8321ca0e8a1e0ac13f23cb668e6f5466c2c57319f6a5cf1cc8e3b1c"
-dependencies = [
- "linked-hash-map",
+ "hashbrown 0.15.2",
 ]
 
 [[package]]
@@ -5686,22 +5772,21 @@ checksum = "68354c5c6bd36d73ff3feceb05efa59b6acb7626617f4962be322a825e61f79a"
 
 [[package]]
 name = "miniz_oxide"
-version = "0.8.0"
+version = "0.8.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "e2d80299ef12ff69b16a84bb182e3b9df68b5a91574d3d4fa6e41b65deec4df1"
+checksum = "b8402cab7aefae129c6977bb0ff1b8fd9a04eb5b51efc50a70bea51cda0c7924"
 dependencies = [
  "adler2",
 ]
 
 [[package]]
 name = "mio"
-version = "1.0.2"
+version = "1.0.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "80e04d1dcff3aae0704555fe5fee3bcfaf3d1fdf8a7e521d5b9d2b42acb52cec"
+checksum = "2886843bf800fba2e3377cff24abf6379b4c4d5c6681eaf9ea5b0d15090450bd"
 dependencies = [
- "hermit-abi 0.3.9",
  "libc",
- "wasi",
+ "wasi 0.11.0+wasi-snapshot-preview1",
  "windows-sys 0.52.0",
 ]
 
@@ -5711,11 +5796,31 @@ version = "0.3.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "9366861eb2a2c436c20b12c8dbec5f798cea6b47ad99216be0282942e2c81ea0"
 
+[[package]]
+name = "moka"
+version = "0.12.10"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "a9321642ca94a4282428e6ea4af8cc2ca4eac48ac7a6a4ea8f33f76d0ce70926"
+dependencies = [
+ "crossbeam-channel",
+ "crossbeam-epoch",
+ "crossbeam-utils",
+ "loom",
+ "parking_lot 0.12.3",
+ "portable-atomic",
+ "rustc_version 0.4.1",
+ "smallvec",
+ "tagptr",
+ "thiserror 1.0.69",
+ "uuid 1.12.1",
+]
+
 [[package]]
 name = "monitoring_api"
 version = "0.1.0"
 dependencies = [
  "eth2",
+ "health_metrics",
  "lighthouse_version",
  "metrics",
  "regex",
@@ -5767,9 +5872,9 @@ dependencies = [
 
 [[package]]
 name = "multihash"
-version = "0.19.2"
+version = "0.19.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "cc41f430805af9d1cf4adae4ed2149c759b877b01d909a1f40256188d09345d2"
+checksum = "6b430e7953c29dd6a09afc29ff0bb69c6e306329ee6794700aee27b76a1aea8d"
 dependencies = [
  "core2",
  "unsigned-varint 0.8.0",
@@ -5791,9 +5896,9 @@ dependencies = [
 
 [[package]]
 name = "native-tls"
-version = "0.2.12"
+version = "0.2.13"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "a8614eb2c83d59d1c8cc974dd3f920198647674a0a035e1af1fa58707e317466"
+checksum = "0dab59f8e050d5df8e4dd87d9206fb6f65a483e20ac9fda365ade4fab353196c"
 dependencies = [
  "libc",
  "log",
@@ -5845,24 +5950,23 @@ dependencies = [
 
 [[package]]
 name = "netlink-proto"
-version = "0.11.3"
+version = "0.11.5"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "86b33524dc0968bfad349684447bfce6db937a9ac3332a1fe60c0c5a5ce63f21"
+checksum = "72452e012c2f8d612410d89eea01e2d9b56205274abb35d53f60200b2ec41d60"
 dependencies = [
  "bytes",
  "futures",
  "log",
  "netlink-packet-core",
  "netlink-sys",
- "thiserror 1.0.69",
- "tokio",
+ "thiserror 2.0.11",
 ]
 
 [[package]]
 name = "netlink-sys"
-version = "0.8.6"
+version = "0.8.7"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "416060d346fbaf1f23f9512963e3e878f1a78e707cb699ba9215761754244307"
+checksum = "16c903aa70590cb93691bf97a767c8d1d6122d2cc9070433deb3bbf36ce8bd23"
 dependencies = [
  "bytes",
  "futures",
@@ -5893,7 +5997,7 @@ dependencies = [
  "genesis",
  "gossipsub",
  "hex",
- "igd-next",
+ "igd-next 0.16.0",
  "itertools 0.10.5",
  "kzg",
  "lighthouse_network",
@@ -5948,7 +6052,7 @@ version = "0.29.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "71e2746dc3a24dd78b3cfcb7be93368c6de9963d30f43a6a73998a9cf4b17b46"
 dependencies = [
- "bitflags 2.6.0",
+ "bitflags 2.8.0",
  "cfg-if",
  "cfg_aliases",
  "libc",
@@ -6082,9 +6186,9 @@ dependencies = [
 
 [[package]]
 name = "object"
-version = "0.36.5"
+version = "0.36.7"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "aedf0a2d09c573ed1d8d85b30c119153926a2b36dce0ab28322c09a117a4683e"
+checksum = "62948e14d923ea95ea2c7c86c71013138b66525b86bdc08d2dcc262bdb497b87"
 dependencies = [
  "memchr",
 ]
@@ -6150,11 +6254,11 @@ dependencies = [
 
 [[package]]
 name = "openssl"
-version = "0.10.68"
+version = "0.10.69"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "6174bc48f102d208783c2c84bf931bb75927a617866870de8a4ea85597f871f5"
+checksum = "f5e534d133a060a3c19daec1eb3e98ec6f4685978834f2dbadfe2ec215bab64e"
 dependencies = [
- "bitflags 2.6.0",
+ "bitflags 2.8.0",
  "cfg-if",
  "foreign-types",
  "libc",
@@ -6171,14 +6275,14 @@ checksum = "a948666b637a0f465e8564c73e89d4dde00d72d4d473cc972f390fc3dcee7d9c"
 dependencies = [
  "proc-macro2",
  "quote",
- "syn 2.0.89",
+ "syn 2.0.96",
 ]
 
 [[package]]
 name = "openssl-probe"
-version = "0.1.5"
+version = "0.1.6"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "ff011a302c396a5197692431fc1948019154afc178baf7d8e37367442a4601cf"
+checksum = "d05e27ee213611ffe7d6348b942e8f942b37114c00cc03cec254295a4a17852e"
 
 [[package]]
 name = "openssl-src"
@@ -6267,16 +6371,15 @@ dependencies = [
 
 [[package]]
 name = "parity-scale-codec"
-version = "3.7.0"
+version = "3.6.12"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "8be4817d39f3272f69c59fe05d0535ae6456c2dc2fa1ba02910296c7e0a5c590"
+checksum = "306800abfa29c7f16596b5970a588435e3d5b3149683d00c12b699cc19f895ee"
 dependencies = [
  "arrayvec",
  "bitvec 1.0.1",
  "byte-slice-cast",
  "impl-trait-for-tuples",
- "parity-scale-codec-derive 3.7.0",
- "rustversion",
+ "parity-scale-codec-derive 3.6.12",
  "serde",
 ]
 
@@ -6294,14 +6397,14 @@ dependencies = [
 
 [[package]]
 name = "parity-scale-codec-derive"
-version = "3.7.0"
+version = "3.6.12"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "8781a75c6205af67215f382092b6e0a4ff3734798523e69073d4bcd294ec767b"
+checksum = "d830939c76d294956402033aee57a6da7b438f2294eb94864c37b0569053a42c"
 dependencies = [
  "proc-macro-crate 3.2.0",
  "proc-macro2",
  "quote",
- "syn 2.0.89",
+ "syn 1.0.109",
 ]
 
 [[package]]
@@ -6353,7 +6456,7 @@ checksum = "1e401f977ab385c9e4e3ab30627d6f26d00e2c73eef317493c4ec6d468726cf8"
 dependencies = [
  "cfg-if",
  "libc",
- "redox_syscall 0.5.7",
+ "redox_syscall 0.5.8",
  "smallvec",
  "windows-targets 0.52.6",
 ]
@@ -6423,12 +6526,12 @@ checksum = "e3148f5046208a5d56bcfc03053e3ca6334e51da8dfb19b6cdc8b306fae3283e"
 
 [[package]]
 name = "pest"
-version = "2.7.14"
+version = "2.7.15"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "879952a81a83930934cbf1786752d6dedc3b1f29e8f8fb2ad1d0a36f377cf442"
+checksum = "8b7cafe60d6cf8e62e1b9b2ea516a089c008945bb5a275416789e7db0bc199dc"
 dependencies = [
  "memchr",
- "thiserror 1.0.69",
+ "thiserror 2.0.11",
  "ucd-trie",
 ]
 
@@ -6444,47 +6547,47 @@ dependencies = [
 
 [[package]]
 name = "phf"
-version = "0.11.2"
+version = "0.11.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "ade2d8b8f33c7333b51bcf0428d37e217e9f32192ae4772156f65063b8ce03dc"
+checksum = "1fd6780a80ae0c52cc120a26a1a42c1ae51b247a253e4e06113d23d2c2edd078"
 dependencies = [
  "phf_shared",
 ]
 
 [[package]]
 name = "phf_shared"
-version = "0.11.2"
+version = "0.11.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "90fcb95eef784c2ac79119d1dd819e162b5da872ce6f3c3abe1e8ca1c082f72b"
+checksum = "67eabc2ef2a60eb7faa00097bd1ffdb5bd28e62bf39990626a582201b7a754e5"
 dependencies = [
  "siphasher",
 ]
 
 [[package]]
 name = "pin-project"
-version = "1.1.7"
+version = "1.1.8"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "be57f64e946e500c8ee36ef6331845d40a93055567ec57e8fae13efd33759b95"
+checksum = "1e2ec53ad785f4d35dac0adea7f7dc6f1bb277ad84a680c7afefeae05d1f5916"
 dependencies = [
  "pin-project-internal",
 ]
 
 [[package]]
 name = "pin-project-internal"
-version = "1.1.7"
+version = "1.1.8"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "3c0f5fad0874fc7abcd4d750e76917eaebbecaa2c20bde22e1dbeeba8beb758c"
+checksum = "d56a66c0c55993aa927429d0f8a0abfd74f084e4d9c192cffed01e418d83eefb"
 dependencies = [
  "proc-macro2",
  "quote",
- "syn 2.0.89",
+ "syn 2.0.96",
 ]
 
 [[package]]
 name = "pin-project-lite"
-version = "0.2.15"
+version = "0.2.16"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "915a1e146535de9163f3987b8944ed8cf49a18bb0056bcebcdcece385cece4ff"
+checksum = "3b3cff922bd51709b605d9ead9aa71031d81447142d828eb4a6eba76fe619f9b"
 
 [[package]]
 name = "pin-utils"
@@ -6562,7 +6665,7 @@ dependencies = [
  "concurrent-queue",
  "hermit-abi 0.4.0",
  "pin-project-lite",
- "rustix 0.38.41",
+ "rustix 0.38.44",
  "tracing",
  "windows-sys 0.59.0",
 ]
@@ -6590,6 +6693,12 @@ dependencies = [
  "universal-hash",
 ]
 
+[[package]]
+name = "portable-atomic"
+version = "1.10.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "280dc24453071f1b63954171985a0b0d30058d287960968b9b2aca264c8d4ee6"
+
 [[package]]
 name = "postgres-protocol"
 version = "0.6.7"
@@ -6653,12 +6762,12 @@ dependencies = [
 
 [[package]]
 name = "prettyplease"
-version = "0.2.25"
+version = "0.2.29"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "64d1ec885c64d0457d564db4ec299b2dae3f9c02808b8ad9c3a089c591b18033"
+checksum = "6924ced06e1f7dfe3fa48d57b9f74f55d8915f5036121bef647ef4b204895fac"
 dependencies = [
  "proc-macro2",
- "syn 2.0.89",
+ "syn 2.0.96",
 ]
 
 [[package]]
@@ -6718,9 +6827,9 @@ dependencies = [
 
 [[package]]
 name = "proc-macro2"
-version = "1.0.92"
+version = "1.0.93"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "37d3544b3f2748c54e147655edb5025752e2303145b5aefb3c3ea2c78b973bb0"
+checksum = "60946a68e5f9d28b0dc1c21bb8a97ee7d018a8b322fa57838ba31cc878e22d99"
 dependencies = [
  "unicode-ident",
 ]
@@ -6775,7 +6884,7 @@ checksum = "440f724eba9f6996b75d63681b0a92b06947f1457076d503a4d2e2c8f56442b8"
 dependencies = [
  "proc-macro2",
  "quote",
- "syn 2.0.89",
+ "syn 2.0.96",
 ]
 
 [[package]]
@@ -6786,7 +6895,7 @@ checksum = "b4c2511913b88df1637da85cc8d96ec8e43a3f8bb8ccb71ee1ac240d6f3df58d"
 dependencies = [
  "bit-set",
  "bit-vec",
- "bitflags 2.6.0",
+ "bitflags 2.8.0",
  "lazy_static",
  "num-traits",
  "rand",
@@ -6800,13 +6909,13 @@ dependencies = [
 
 [[package]]
 name = "proptest-derive"
-version = "0.5.0"
+version = "0.5.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "6ff7ff745a347b87471d859a377a9a404361e7efc2a971d73424a6d183c0fc77"
+checksum = "4ee1c9ac207483d5e7db4940700de86a9aae46ef90c48b57f99fe7edb8345e49"
 dependencies = [
  "proc-macro2",
  "quote",
- "syn 2.0.89",
+ "syn 2.0.96",
 ]
 
 [[package]]
@@ -6907,10 +7016,10 @@ dependencies = [
  "pin-project-lite",
  "quinn-proto",
  "quinn-udp",
- "rustc-hash 2.0.0",
- "rustls 0.23.18",
+ "rustc-hash 2.1.0",
+ "rustls 0.23.21",
  "socket2",
- "thiserror 2.0.3",
+ "thiserror 2.0.11",
  "tokio",
  "tracing",
 ]
@@ -6922,14 +7031,14 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "a2fe5ef3495d7d2e377ff17b1a8ce2ee2ec2a18cde8b6ad6619d65d0701c135d"
 dependencies = [
  "bytes",
- "getrandom",
+ "getrandom 0.2.15",
  "rand",
  "ring 0.17.8",
- "rustc-hash 2.0.0",
- "rustls 0.23.18",
+ "rustc-hash 2.1.0",
+ "rustls 0.23.21",
  "rustls-pki-types",
  "slab",
- "thiserror 2.0.3",
+ "thiserror 2.0.11",
  "tinyvec",
  "tracing",
  "web-time",
@@ -6937,9 +7046,9 @@ dependencies = [
 
 [[package]]
 name = "quinn-udp"
-version = "0.5.7"
+version = "0.5.9"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "7d5a626c6807713b15cac82a6acaccd6043c9a5408c24baae07611fec3f243da"
+checksum = "1c40286217b4ba3a71d644d752e6a0b71f13f1b6a2c5311acfcbe0c2418ed904"
 dependencies = [
  "cfg_aliases",
  "libc",
@@ -6951,9 +7060,9 @@ dependencies = [
 
 [[package]]
 name = "quote"
-version = "1.0.37"
+version = "1.0.38"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "b5b9d34b8991d19d98081b46eacdd8eb58c6f2b201139f7c5f643cc155a633af"
+checksum = "0e4dccaaaf89514f546c693ddc140f729f958c247918a13380cccc6078391acc"
 dependencies = [
  "proc-macro2",
 ]
@@ -7019,7 +7128,7 @@ version = "0.6.4"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "ec0be4795e2f6a28069bec0b5ff3e2ac9bafc99e6a9a7dc3547996c5c816922c"
 dependencies = [
- "getrandom",
+ "getrandom 0.2.15",
 ]
 
 [[package]]
@@ -7065,9 +7174,9 @@ dependencies = [
 
 [[package]]
 name = "redb"
-version = "2.2.0"
+version = "2.4.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "84b1de48a7cf7ba193e81e078d17ee2b786236eed1d3f7c60f8a09545efc4925"
+checksum = "ea0a72cd7140de9fc3e318823b883abf819c20d478ec89ce880466dc2ef263c6"
 dependencies = [
  "libc",
 ]
@@ -7083,11 +7192,11 @@ dependencies = [
 
 [[package]]
 name = "redox_syscall"
-version = "0.5.7"
+version = "0.5.8"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "9b6dfecf2c74bce2466cabf93f6664d6998a69eb21e39f4207930065b27b771f"
+checksum = "03a862b389f93e68874fbf580b9de08dd02facb9a788ebadaf4a3fd33cf58834"
 dependencies = [
- "bitflags 2.6.0",
+ "bitflags 2.8.0",
 ]
 
 [[package]]
@@ -7096,7 +7205,7 @@ version = "0.4.6"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "ba009ff324d1fc1b900bd1fdb31564febe58a8ccc8a6fdbb93b543d33b13ca43"
 dependencies = [
- "getrandom",
+ "getrandom 0.2.15",
  "libredox",
  "thiserror 1.0.69",
 ]
@@ -7156,10 +7265,10 @@ dependencies = [
  "encoding_rs",
  "futures-core",
  "futures-util",
- "h2",
+ "h2 0.3.26",
  "http 0.2.12",
  "http-body 0.4.6",
- "hyper 0.14.31",
+ "hyper 0.14.32",
  "hyper-rustls",
  "hyper-tls",
  "ipnet",
@@ -7261,7 +7370,7 @@ checksum = "c17fa4cb658e3583423e915b9f3acc01cceaee1860e33d59ebae66adc3a2dc0d"
 dependencies = [
  "cc",
  "cfg-if",
- "getrandom",
+ "getrandom 0.2.15",
  "libc",
  "spin 0.9.8",
  "untrusted 0.9.0",
@@ -7334,19 +7443,21 @@ dependencies = [
 
 [[package]]
 name = "ruint"
-version = "1.12.3"
+version = "1.12.4"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "2c3cc4c2511671f327125da14133d0c5c5d137f006a1017a16f557bc85b16286"
+checksum = "f5ef8fb1dd8de3870cb8400d51b4c2023854bbafd5431a3ac7e7317243e22d2f"
 dependencies = [
  "alloy-rlp",
  "arbitrary",
  "ark-ff 0.3.0",
  "ark-ff 0.4.2",
  "bytes",
- "fastrlp",
+ "fastrlp 0.3.1",
+ "fastrlp 0.4.0",
  "num-bigint",
+ "num-integer",
  "num-traits",
- "parity-scale-codec 3.7.0",
+ "parity-scale-codec 3.6.12",
  "primitive-types 0.12.2",
  "proptest",
  "rand",
@@ -7405,9 +7516,9 @@ checksum = "08d43f7aa6b08d49f382cde6a7982047c3426db949b1424bc4b7ec9ae12c6ce2"
 
 [[package]]
 name = "rustc-hash"
-version = "2.0.0"
+version = "2.1.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "583034fd73374156e66797ed8e5b0d5690409c9226b22d87cb7f19821c05d152"
+checksum = "c7fb8039b3032c191086b10f11f319a6e99e1e82889c5cc6046f515c9db1d497"
 
 [[package]]
 name = "rustc-hex"
@@ -7430,7 +7541,7 @@ version = "0.4.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "cfcb3a22ef46e85b45de6ee7e79d063319ebb6594faafcf1c225ea92ab6e9b92"
 dependencies = [
- "semver 1.0.23",
+ "semver 1.0.25",
 ]
 
 [[package]]
@@ -7458,15 +7569,15 @@ dependencies = [
 
 [[package]]
 name = "rustix"
-version = "0.38.41"
+version = "0.38.44"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "d7f649912bc1495e167a6edee79151c84b1bad49748cb4f1f1167f459f6224f6"
+checksum = "fdb5bc1ae2baa591800df16c9ca78619bf65c0488b41b96ccec5d11220d8c154"
 dependencies = [
- "bitflags 2.6.0",
+ "bitflags 2.8.0",
  "errno",
  "libc",
- "linux-raw-sys 0.4.14",
- "windows-sys 0.52.0",
+ "linux-raw-sys 0.4.15",
+ "windows-sys 0.59.0",
 ]
 
 [[package]]
@@ -7497,9 +7608,9 @@ dependencies = [
 
 [[package]]
 name = "rustls"
-version = "0.23.18"
+version = "0.23.21"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "9c9cc1d47e243d655ace55ed38201c19ae02c148ae56412ab8750e8f0166ab7f"
+checksum = "8f287924602bf649d949c63dc8ac8b235fa5387d394020705b80c4eb597ce5b8"
 dependencies = [
  "once_cell",
  "ring 0.17.8",
@@ -7529,9 +7640,9 @@ dependencies = [
 
 [[package]]
 name = "rustls-pki-types"
-version = "1.10.0"
+version = "1.11.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "16f1201b3c9a7ee8039bcadc17b7e605e2945b27eee7631788c1bd2b0643674b"
+checksum = "917ce264624a4b4db1c364dcc35bfca9ded014d0a958cd47ad3e960e988ea51c"
 dependencies = [
  "web-time",
 ]
@@ -7559,9 +7670,9 @@ dependencies = [
 
 [[package]]
 name = "rustversion"
-version = "1.0.18"
+version = "1.0.19"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "0e819f2bc632f285be6d7cd36e25940d45b2391dd6d9b939e79de557f7014248"
+checksum = "f7c45b9784283f1b2e7fb61b42047c2fd678ef0960d4f6f1eba131594cc369d4"
 
 [[package]]
 name = "rusty-fork"
@@ -7588,9 +7699,9 @@ dependencies = [
 
 [[package]]
 name = "ryu"
-version = "1.0.18"
+version = "1.0.19"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "f3cb5ba0dc43242ce17de99c180e96db90b235b8a9fdc9543c96d2209116bd9f"
+checksum = "6ea1a2d0a644769cc99faa24c3ad26b379b786fe7c36fd3c546254801650e6dd"
 
 [[package]]
 name = "safe_arith"
@@ -7622,7 +7733,7 @@ checksum = "346a3b32eba2640d17a9cb5927056b08f3de90f65b72fe09402c2ad07d684d0b"
 dependencies = [
  "cfg-if",
  "derive_more 1.0.0",
- "parity-scale-codec 3.7.0",
+ "parity-scale-codec 3.6.12",
  "scale-info-derive",
 ]
 
@@ -7635,7 +7746,7 @@ dependencies = [
  "proc-macro-crate 3.2.0",
  "proc-macro2",
  "quote",
- "syn 2.0.89",
+ "syn 2.0.96",
 ]
 
 [[package]]
@@ -7724,7 +7835,7 @@ version = "2.11.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "897b2245f0b511c87893af39b033e5ca9cce68824c4d7e7630b5a1d339658d02"
 dependencies = [
- "bitflags 2.6.0",
+ "bitflags 2.8.0",
  "core-foundation",
  "core-foundation-sys",
  "libc",
@@ -7733,9 +7844,9 @@ dependencies = [
 
 [[package]]
 name = "security-framework-sys"
-version = "2.12.1"
+version = "2.14.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "fa39c7303dc58b5543c94d22c1766b0d31f2ee58306363ea622b10bbc075eaa2"
+checksum = "49db231d56a190491cb4aeda9527f1ad45345af50b0851622a7adb8c03b01c32"
 dependencies = [
  "core-foundation-sys",
  "libc",
@@ -7752,9 +7863,9 @@ dependencies = [
 
 [[package]]
 name = "semver"
-version = "1.0.23"
+version = "1.0.25"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "61697e0a1c7e512e84a621326239844a24d8207b4669b41bc18b32ea5cbf988b"
+checksum = "f79dfe2d285b0488816f30e700a7438c5a73d816b5b7d3ac72fbc48b0d185e03"
 dependencies = [
  "serde",
 ]
@@ -7790,9 +7901,9 @@ dependencies = [
 
 [[package]]
 name = "serde"
-version = "1.0.215"
+version = "1.0.217"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "6513c1ad0b11a9376da888e3e0baa0077f1aed55c17f50e7b2397136129fb88f"
+checksum = "02fc4265df13d6fa1d00ecff087228cc0a2b5f3c0e87e258d8b94a156e984c70"
 dependencies = [
  "serde_derive",
 ]
@@ -7809,20 +7920,20 @@ dependencies = [
 
 [[package]]
 name = "serde_derive"
-version = "1.0.215"
+version = "1.0.217"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "ad1e866f866923f252f05c889987993144fb74e722403468a4ebd70c3cd756c0"
+checksum = "5a9bf7cf98d04a2b28aead066b7496853d4779c9cc183c440dbac457641e19a0"
 dependencies = [
  "proc-macro2",
  "quote",
- "syn 2.0.89",
+ "syn 2.0.96",
 ]
 
 [[package]]
 name = "serde_json"
-version = "1.0.133"
+version = "1.0.138"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "c7fceb2473b9166b2294ef05efcb65a3db80803f0b03ef86a5fc88a2b85ee377"
+checksum = "d434192e7da787e94a6ea7e9670b26a036d0ca41e0b7efb2676dd32bae872949"
 dependencies = [
  "itoa",
  "memchr",
@@ -7848,7 +7959,7 @@ checksum = "6c64451ba24fc7a6a2d60fc75dd9c83c90903b19028d4eff35e88fc1e86564e9"
 dependencies = [
  "proc-macro2",
  "quote",
- "syn 2.0.89",
+ "syn 2.0.96",
 ]
 
 [[package]]
@@ -7900,7 +8011,7 @@ version = "0.9.34+deprecated"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "6a8b1a1a2ebf674015cc02edccce75287f1a0130d394307b36743c2f5d504b47"
 dependencies = [
- "indexmap 2.6.0",
+ "indexmap 2.7.1",
  "itoa",
  "ryu",
  "serde",
@@ -8036,13 +8147,13 @@ dependencies = [
 
 [[package]]
 name = "simple_asn1"
-version = "0.6.2"
+version = "0.6.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "adc4e5204eb1910f40f9cfa375f6f05b68c3abac4b6fd879c8ff5e7ae8a0a085"
+checksum = "297f631f50729c8c99b84667867963997ec0b50f32b2a7dbcab828ef0541e8bb"
 dependencies = [
  "num-bigint",
  "num-traits",
- "thiserror 1.0.69",
+ "thiserror 2.0.11",
  "time",
 ]
 
@@ -8067,9 +8178,9 @@ dependencies = [
 
 [[package]]
 name = "siphasher"
-version = "0.3.11"
+version = "1.0.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "38b58827f4464d87d377d175e90bf58eb00fd8716ff0a62f80356b5e61555d0d"
+checksum = "56199f7ddabf13fe5074ce809e7d3f42b42ae711800501b5b16ea82ad029c39d"
 
 [[package]]
 name = "slab"
@@ -8292,9 +8403,9 @@ dependencies = [
 
 [[package]]
 name = "socket2"
-version = "0.5.7"
+version = "0.5.8"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "ce305eb0b4296696835b71df73eb912e0f1ffd2556a501fcede6e0c50349191c"
+checksum = "c970269d99b64e60ec3bd6ad27270092a5394c4e309314b18ae3fe575695fbe8"
 dependencies = [
  "libc",
  "windows-sys 0.52.0",
@@ -8419,6 +8530,7 @@ dependencies = [
  "metrics",
  "parking_lot 0.12.3",
  "rand",
+ "redb",
  "safe_arith",
  "serde",
  "slog",
@@ -8521,9 +8633,9 @@ dependencies = [
 
 [[package]]
 name = "syn"
-version = "2.0.89"
+version = "2.0.96"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "44d46482f1c1c87acd84dea20c1bf5ebff4c757009ed6bf19cfd36fb10e92c4e"
+checksum = "d5d0adab1ae378d7f53bdebc67a39f1f151407ef230f0ce2883572f5d8985c80"
 dependencies = [
  "proc-macro2",
  "quote",
@@ -8550,7 +8662,7 @@ checksum = "c8af7666ab7b6390ab78131fb5b0fce11d6b7a6951602017c35fa82800708971"
 dependencies = [
  "proc-macro2",
  "quote",
- "syn 2.0.89",
+ "syn 2.0.96",
 ]
 
 [[package]]
@@ -8585,7 +8697,7 @@ version = "0.6.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "3c879d448e9d986b661742763247d3693ed13609438cf3d006f51f5368a5ba6b"
 dependencies = [
- "bitflags 2.6.0",
+ "bitflags 2.8.0",
  "core-foundation",
  "system-configuration-sys 0.6.0",
 ]
@@ -8621,6 +8733,12 @@ dependencies = [
  "types",
 ]
 
+[[package]]
+name = "tagptr"
+version = "0.2.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "7b2093cf4c8eb1e67749a6762251bc9cd836b6fc171623bd0a9d324d37af2417"
+
 [[package]]
 name = "take_mut"
 version = "0.2.2"
@@ -8662,14 +8780,15 @@ dependencies = [
 
 [[package]]
 name = "tempfile"
-version = "3.14.0"
+version = "3.16.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "28cce251fcbc87fac86a866eeb0d6c2d536fc16d06f184bb61aeae11aa4cee0c"
+checksum = "38c246215d7d24f48ae091a2902398798e05d978b24315d6efbc00ede9a8bb91"
 dependencies = [
  "cfg-if",
  "fastrand",
+ "getrandom 0.3.1",
  "once_cell",
- "rustix 0.38.41",
+ "rustix 0.38.44",
  "windows-sys 0.59.0",
 ]
 
@@ -8695,11 +8814,11 @@ dependencies = [
 
 [[package]]
 name = "terminal_size"
-version = "0.4.0"
+version = "0.4.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "4f599bd7ca042cfdf8f4512b277c02ba102247820f9d9d4a9f521f496751a6ef"
+checksum = "5352447f921fda68cf61b4101566c0bdb5104eff6804d0678e5227580ab6a4e9"
 dependencies = [
- "rustix 0.38.41",
+ "rustix 0.38.44",
  "windows-sys 0.59.0",
 ]
 
@@ -8747,11 +8866,11 @@ dependencies = [
 
 [[package]]
 name = "thiserror"
-version = "2.0.3"
+version = "2.0.11"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "c006c85c7651b3cf2ada4584faa36773bd07bac24acfb39f3c431b36d7e667aa"
+checksum = "d452f284b73e6d76dd36758a0c8684b1d5be31f92b89d07fd5822175732206fc"
 dependencies = [
- "thiserror-impl 2.0.3",
+ "thiserror-impl 2.0.11",
 ]
 
 [[package]]
@@ -8762,18 +8881,18 @@ checksum = "4fee6c4efc90059e10f81e6d42c60a18f76588c3d74cb83a0b242a2b6c7504c1"
 dependencies = [
  "proc-macro2",
  "quote",
- "syn 2.0.89",
+ "syn 2.0.96",
 ]
 
 [[package]]
 name = "thiserror-impl"
-version = "2.0.3"
+version = "2.0.11"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "f077553d607adc1caf65430528a576c757a71ed73944b66ebb58ef2bbd243568"
+checksum = "26afc1baea8a989337eeb52b6e72a039780ce45c3edfcc9c5b9d112feeb173c2"
 dependencies = [
  "proc-macro2",
  "quote",
- "syn 2.0.89",
+ "syn 2.0.96",
 ]
 
 [[package]]
@@ -8828,9 +8947,9 @@ dependencies = [
 
 [[package]]
 name = "time"
-version = "0.3.36"
+version = "0.3.37"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "5dfd88e563464686c916c7e46e623e520ddc6d79fa6641390f2e3fa86e83e885"
+checksum = "35e7868883861bd0e56d9ac6efcaaca0d6d5d82a2a7ec8209ff492c07cf37b21"
 dependencies = [
  "deranged",
  "itoa",
@@ -8849,9 +8968,9 @@ checksum = "ef927ca75afb808a4d64dd374f00a2adf8d0fcff8e7b184af886c3c87ec4a3f3"
 
 [[package]]
 name = "time-macros"
-version = "0.2.18"
+version = "0.2.19"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "3f252a68540fde3a3877aeea552b832b40ab9a69e318efd078774a01ddee1ccf"
+checksum = "2834e6017e3e5e4b9834939793b282bc03b37a3336245fa820e35e233e2a85de"
 dependencies = [
  "num-conv",
  "time-core",
@@ -8918,9 +9037,9 @@ dependencies = [
 
 [[package]]
 name = "tinyvec"
-version = "1.8.0"
+version = "1.8.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "445e881f4f6d382d5f27c034e25eb92edd7c784ceab92a0937db7f2e9471b938"
+checksum = "022db8904dfa342efe721985167e9fcd16c29b226db4397ed752a761cfce81e8"
 dependencies = [
  "tinyvec_macros",
 ]
@@ -8933,9 +9052,9 @@ checksum = "1f3ccbac311fea05f86f61904b462b55fb3df8837a366dfc601a0161d0532f20"
 
 [[package]]
 name = "tokio"
-version = "1.41.1"
+version = "1.43.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "22cfb5bee7a6a52939ca9224d6ac897bb669134078daa8735560897f69de4d33"
+checksum = "3d61fa4ffa3de412bfea335c6ecff681de2b609ba3c77ef3e00e521813a9ed9e"
 dependencies = [
  "backtrace",
  "bytes",
@@ -8960,13 +9079,13 @@ dependencies = [
 
 [[package]]
 name = "tokio-macros"
-version = "2.4.0"
+version = "2.5.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "693d596312e88961bc67d7f1f97af8a70227d9f90c31bba5806eec004978d752"
+checksum = "6e06d43f1345a3bcd39f6a56dbb7dcab2ba47e68e8ac134855e7e2bdbaf8cab8"
 dependencies = [
  "proc-macro2",
  "quote",
- "syn 2.0.89",
+ "syn 2.0.96",
 ]
 
 [[package]]
@@ -9028,9 +9147,9 @@ dependencies = [
 
 [[package]]
 name = "tokio-stream"
-version = "0.1.16"
+version = "0.1.17"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "4f4e6ce100d0eb49a2734f8c0812bcd324cf357d21810932c5df6b96ef2b86f1"
+checksum = "eca58d7bba4a75707817a2c44174253f9236b2d5fbd055602e9d5c07c139a047"
 dependencies = [
  "futures-core",
  "pin-project-lite",
@@ -9040,9 +9159,9 @@ dependencies = [
 
 [[package]]
 name = "tokio-util"
-version = "0.7.12"
+version = "0.7.13"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "61e7c3654c13bcd040d4a03abee2c75b1d14a37b423cf5a813ceae1cc903ec6a"
+checksum = "d7fcaa8d55a2bdd6b83ace262b016eca0d79ee02818c5c1bcdf0305114081078"
 dependencies = [
  "bytes",
  "futures-core",
@@ -9089,7 +9208,7 @@ version = "0.19.15"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "1b5bb770da30e5cbfde35a2d7b9b8a2c4b8ef89548a7a6aeab5c9a576e3e7421"
 dependencies = [
- "indexmap 2.6.0",
+ "indexmap 2.7.1",
  "toml_datetime",
  "winnow 0.5.40",
 ]
@@ -9100,23 +9219,23 @@ version = "0.22.22"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "4ae48d6208a266e853d946088ed816055e556cc6028c5e8e2b84d9fa5dd7c7f5"
 dependencies = [
- "indexmap 2.6.0",
+ "indexmap 2.7.1",
  "serde",
  "serde_spanned",
  "toml_datetime",
- "winnow 0.6.20",
+ "winnow 0.6.25",
 ]
 
 [[package]]
 name = "tower"
-version = "0.5.1"
+version = "0.5.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "2873938d487c3cfb9aed7546dc9f2711d867c9f90c46b889989a2cb84eba6b4f"
+checksum = "d039ad9159c98b70ecfd540b2573b97f7f52c3e8d9f8ad57a24b916a536975f9"
 dependencies = [
  "futures-core",
  "futures-util",
  "pin-project-lite",
- "sync_wrapper 0.1.2",
+ "sync_wrapper 1.0.2",
  "tokio",
  "tower-layer",
  "tower-service",
@@ -9137,9 +9256,9 @@ checksum = "8df9b6e13f2d32c91b9bd719c00d1958837bc7dec474d94952798cc8e69eeec3"
 
 [[package]]
 name = "tracing"
-version = "0.1.40"
+version = "0.1.41"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "c3523ab5a71916ccf420eebdf5521fcef02141234bbc0b8a49f2fdc4544364ef"
+checksum = "784e0ac535deb450455cbfa28a6f0df145ea1bb7ae51b821cf5e7927fdcfbdd0"
 dependencies = [
  "log",
  "pin-project-lite",
@@ -9161,20 +9280,20 @@ dependencies = [
 
 [[package]]
 name = "tracing-attributes"
-version = "0.1.27"
+version = "0.1.28"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "34704c8d6ebcbc939824180af020566b01a7c01f80641264eba0999f6c2b6be7"
+checksum = "395ae124c09f9e6918a2310af6038fba074bcf474ac352496d5910dd59a2226d"
 dependencies = [
  "proc-macro2",
  "quote",
- "syn 2.0.89",
+ "syn 2.0.96",
 ]
 
 [[package]]
 name = "tracing-core"
-version = "0.1.32"
+version = "0.1.33"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "c06d3da6113f116aaee68e4d601191614c9053067f9ab7f6edbcb161237daa54"
+checksum = "e672c95779cf947c5311f83787af4fa8fffd12fb27e4993211a84bdfd9610f9c"
 dependencies = [
  "once_cell",
  "valuable",
@@ -9203,9 +9322,9 @@ dependencies = [
 
 [[package]]
 name = "tracing-subscriber"
-version = "0.3.18"
+version = "0.3.19"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "ad0f048c97dbd9faa9b7df56362b8ebcaa52adb06b498c050d2f4e32f90a7a8b"
+checksum = "e8189decb5ac0fa7bc8b96b7cb9b2701d60d48805aca84a238004d665fcc4008"
 dependencies = [
  "matchers",
  "nu-ansi-term",
@@ -9258,7 +9377,7 @@ dependencies = [
  "darling 0.20.10",
  "proc-macro2",
  "quote",
- "syn 2.0.89",
+ "syn 2.0.96",
 ]
 
 [[package]]
@@ -9390,21 +9509,21 @@ checksum = "ccb97dac3243214f8d8507998906ca3e2e0b900bf9bf4870477f125b82e68f6e"
 
 [[package]]
 name = "unicase"
-version = "2.8.0"
+version = "2.8.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "7e51b68083f157f853b6379db119d1c1be0e6e4dec98101079dec41f6f5cf6df"
+checksum = "75b844d17643ee918803943289730bec8aac480150456169e647ed0b576ba539"
 
 [[package]]
 name = "unicode-bidi"
-version = "0.3.17"
+version = "0.3.18"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "5ab17db44d7388991a428b2ee655ce0c212e862eff1768a455c58f9aad6e7893"
+checksum = "5c1cb5db39152898a79168971543b1cb5020dff7fe43c8dc468b0885f5e29df5"
 
 [[package]]
 name = "unicode-ident"
-version = "1.0.14"
+version = "1.0.16"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "adb9e6ca4f869e1180728b7950e35922a7fc6397f7b641499e8f3ef06e50dc83"
+checksum = "a210d160f08b701c8721ba1c726c11662f877ea6b7094007e1ca9a1041945034"
 
 [[package]]
 name = "unicode-normalization"
@@ -9487,7 +9606,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "32f8b686cadd1473f4bd0117a5d28d36b1ade384ea9b5069a1c40aefed7fda60"
 dependencies = [
  "form_urlencoded",
- "idna 1.0.3",
+ "idna",
  "percent-encoding",
 ]
 
@@ -9515,10 +9634,19 @@ version = "0.8.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "bc5cf98d8186244414c848017f0e2676b3fcb46807f6668a97dfe67359a3c4b7"
 dependencies = [
- "getrandom",
+ "getrandom 0.2.15",
  "serde",
 ]
 
+[[package]]
+name = "uuid"
+version = "1.12.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "b3758f5e68192bb96cc8f9b7e2c2cfdabb435499a28499a42f8f984092adad4b"
+dependencies = [
+ "getrandom 0.2.15",
+]
+
 [[package]]
 name = "validator_client"
 version = "0.3.5"
@@ -9534,7 +9662,7 @@ dependencies = [
  "eth2",
  "fdlimit",
  "graffiti_file",
- "hyper 1.5.1",
+ "hyper 1.6.0",
  "initialized_validators",
  "metrics",
  "monitoring_api",
@@ -9561,7 +9689,6 @@ dependencies = [
  "bls",
  "deposit_contract",
  "derivative",
- "directory",
  "eth2_keystore",
  "filesystem",
  "hex",
@@ -9589,6 +9716,7 @@ dependencies = [
  "filesystem",
  "futures",
  "graffiti_file",
+ "health_metrics",
  "initialized_validators",
  "itertools 0.10.5",
  "lighthouse_version",
@@ -9621,6 +9749,7 @@ dependencies = [
 name = "validator_http_metrics"
 version = "0.1.0"
 dependencies = [
+ "health_metrics",
  "lighthouse_version",
  "malloc_utils",
  "metrics",
@@ -9675,6 +9804,7 @@ dependencies = [
  "beacon_node_fallback",
  "bls",
  "doppelganger_service",
+ "either",
  "environment",
  "eth2",
  "futures",
@@ -9710,9 +9840,9 @@ dependencies = [
 
 [[package]]
 name = "valuable"
-version = "0.1.0"
+version = "0.1.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "830b7e5d4d90034032940e4ace0d9a9a057e7a45cd94e6c007832e39edb82f6d"
+checksum = "ba73ea9cf16a25df0c8caa16c51acb937d5712a8429db78a3ee29d5dcacd3a65"
 
 [[package]]
 name = "vcpkg"
@@ -9777,7 +9907,7 @@ dependencies = [
  "futures-util",
  "headers",
  "http 0.2.12",
- "hyper 0.14.31",
+ "hyper 0.14.32",
  "log",
  "mime",
  "mime_guess",
@@ -9799,7 +9929,6 @@ dependencies = [
 name = "warp_utils"
 version = "0.1.0"
 dependencies = [
- "beacon_chain",
  "bytes",
  "eth2",
  "headers",
@@ -9808,7 +9937,6 @@ dependencies = [
  "serde",
  "serde_array_query",
  "serde_json",
- "state_processing",
  "tokio",
  "types",
  "warp",
@@ -9820,6 +9948,15 @@ version = "0.11.0+wasi-snapshot-preview1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "9c8d87e72b64a3b4db28d11ce29237c246188f4f51057d65a7eab63b7987e423"
 
+[[package]]
+name = "wasi"
+version = "0.13.3+wasi-0.2.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "26816d2e1a4a36a2940b96c5296ce403917633dff8f3440e9b236ed6f6bacad2"
+dependencies = [
+ "wit-bindgen-rt",
+]
+
 [[package]]
 name = "wasite"
 version = "0.1.0"
@@ -9828,47 +9965,48 @@ checksum = "b8dad83b4f25e74f184f64c43b150b91efe7647395b42289f38e50566d82855b"
 
 [[package]]
 name = "wasm-bindgen"
-version = "0.2.95"
+version = "0.2.100"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "128d1e363af62632b8eb57219c8fd7877144af57558fb2ef0368d0087bddeb2e"
+checksum = "1edc8929d7499fc4e8f0be2262a241556cfc54a0bea223790e71446f2aab1ef5"
 dependencies = [
  "cfg-if",
  "once_cell",
+ "rustversion",
  "wasm-bindgen-macro",
 ]
 
 [[package]]
 name = "wasm-bindgen-backend"
-version = "0.2.95"
+version = "0.2.100"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "cb6dd4d3ca0ddffd1dd1c9c04f94b868c37ff5fac97c30b97cff2d74fce3a358"
+checksum = "2f0a0651a5c2bc21487bde11ee802ccaf4c51935d0d3d42a6101f98161700bc6"
 dependencies = [
  "bumpalo",
  "log",
- "once_cell",
  "proc-macro2",
  "quote",
- "syn 2.0.89",
+ "syn 2.0.96",
  "wasm-bindgen-shared",
 ]
 
 [[package]]
 name = "wasm-bindgen-futures"
-version = "0.4.45"
+version = "0.4.50"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "cc7ec4f8827a71586374db3e87abdb5a2bb3a15afed140221307c3ec06b1f63b"
+checksum = "555d470ec0bc3bb57890405e5d4322cc9ea83cebb085523ced7be4144dac1e61"
 dependencies = [
  "cfg-if",
  "js-sys",
+ "once_cell",
  "wasm-bindgen",
  "web-sys",
 ]
 
 [[package]]
 name = "wasm-bindgen-macro"
-version = "0.2.95"
+version = "0.2.100"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "e79384be7f8f5a9dd5d7167216f022090cf1f9ec128e6e6a482a2cb5c5422c56"
+checksum = "7fe63fc6d09ed3792bd0897b314f53de8e16568c2b3f7982f468c0bf9bd0b407"
 dependencies = [
  "quote",
  "wasm-bindgen-macro-support",
@@ -9876,22 +10014,25 @@ dependencies = [
 
 [[package]]
 name = "wasm-bindgen-macro-support"
-version = "0.2.95"
+version = "0.2.100"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "26c6ab57572f7a24a4985830b120de1594465e5d500f24afe89e16b4e833ef68"
+checksum = "8ae87ea40c9f689fc23f209965b6fb8a99ad69aeeb0231408be24920604395de"
 dependencies = [
  "proc-macro2",
  "quote",
- "syn 2.0.89",
+ "syn 2.0.96",
  "wasm-bindgen-backend",
  "wasm-bindgen-shared",
 ]
 
 [[package]]
 name = "wasm-bindgen-shared"
-version = "0.2.95"
+version = "0.2.100"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "65fc09f10666a9f147042251e0dda9c18f166ff7de300607007e96bdebc1068d"
+checksum = "1a05d73b933a847d6cccdda8f838a22ff101ad9bf93e33684f39c1f5f0eece3d"
+dependencies = [
+ "unicode-ident",
+]
 
 [[package]]
 name = "wasm-streams"
@@ -9936,7 +10077,7 @@ dependencies = [
  "env_logger 0.9.3",
  "eth2",
  "http_api",
- "hyper 1.5.1",
+ "hyper 1.6.0",
  "log",
  "logging",
  "network",
@@ -9957,9 +10098,9 @@ dependencies = [
 
 [[package]]
 name = "web-sys"
-version = "0.3.72"
+version = "0.3.77"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "f6488b90108c040df0fe62fa815cbdee25124641df01814dd7282749234c6112"
+checksum = "33b6dd2ef9186f1f2072e409e99cd22a975331a6b3591b12c764e0e55c60d5d2"
 dependencies = [
  "js-sys",
  "wasm-bindgen",
@@ -10018,7 +10159,7 @@ dependencies = [
  "either",
  "home",
  "once_cell",
- "rustix 0.38.41",
+ "rustix 0.38.44",
 ]
 
 [[package]]
@@ -10027,7 +10168,7 @@ version = "1.5.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "372d5b87f58ec45c384ba03563b03544dc5fadc3983e434b286913f5b4a9bb6d"
 dependencies = [
- "redox_syscall 0.5.7",
+ "redox_syscall 0.5.8",
  "wasite",
  "web-sys",
 ]
@@ -10085,6 +10226,16 @@ dependencies = [
  "windows-targets 0.52.6",
 ]
 
+[[package]]
+name = "windows"
+version = "0.58.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "dd04d41d93c4992d421894c18c8b43496aa748dd4c081bac0dc93eb0489272b6"
+dependencies = [
+ "windows-core 0.58.0",
+ "windows-targets 0.52.6",
+]
+
 [[package]]
 name = "windows-acl"
 version = "0.3.0"
@@ -10112,10 +10263,45 @@ version = "0.53.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "9dcc5b895a6377f1ab9fa55acedab1fd5ac0db66ad1e6c7f47e28a22e446a5dd"
 dependencies = [
- "windows-result",
+ "windows-result 0.1.2",
  "windows-targets 0.52.6",
 ]
 
+[[package]]
+name = "windows-core"
+version = "0.58.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "6ba6d44ec8c2591c134257ce647b7ea6b20335bf6379a27dac5f1641fcf59f99"
+dependencies = [
+ "windows-implement",
+ "windows-interface",
+ "windows-result 0.2.0",
+ "windows-strings",
+ "windows-targets 0.52.6",
+]
+
+[[package]]
+name = "windows-implement"
+version = "0.58.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "2bbd5b46c938e506ecbce286b6628a02171d56153ba733b6c741fc627ec9579b"
+dependencies = [
+ "proc-macro2",
+ "quote",
+ "syn 2.0.96",
+]
+
+[[package]]
+name = "windows-interface"
+version = "0.58.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "053c4c462dc91d3b1504c6fe5a726dd15e216ba718e84a0e46a88fbe5ded3515"
+dependencies = [
+ "proc-macro2",
+ "quote",
+ "syn 2.0.96",
+]
+
 [[package]]
 name = "windows-result"
 version = "0.1.2"
@@ -10125,6 +10311,25 @@ dependencies = [
  "windows-targets 0.52.6",
 ]
 
+[[package]]
+name = "windows-result"
+version = "0.2.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "1d1043d8214f791817bab27572aaa8af63732e11bf84aa21a45a78d6c317ae0e"
+dependencies = [
+ "windows-targets 0.52.6",
+]
+
+[[package]]
+name = "windows-strings"
+version = "0.1.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "4cd9b125c486025df0eabcb585e62173c6c9eddcec5d117d3b6e8c30e2ee4d10"
+dependencies = [
+ "windows-result 0.2.0",
+ "windows-targets 0.52.6",
+]
+
 [[package]]
 name = "windows-sys"
 version = "0.45.0"
@@ -10350,9 +10555,9 @@ dependencies = [
 
 [[package]]
 name = "winnow"
-version = "0.6.20"
+version = "0.6.25"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "36c1fec1a2bb5866f07c25f68c26e565c4c200aebb96d7e55710c19d3e8ac49b"
+checksum = "ad699df48212c6cc6eb4435f35500ac6fd3b9913324f938aea302022ce19d310"
 dependencies = [
  "memchr",
 ]
@@ -10367,6 +10572,15 @@ dependencies = [
  "windows-sys 0.48.0",
 ]
 
+[[package]]
+name = "wit-bindgen-rt"
+version = "0.33.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "3268f3d866458b787f390cf61f4bbb563b922d091359f9608842999eaee3943c"
+dependencies = [
+ "bitflags 2.8.0",
+]
+
 [[package]]
 name = "write16"
 version = "1.0.0"
@@ -10458,9 +10672,9 @@ dependencies = [
 
 [[package]]
 name = "xml-rs"
-version = "0.8.23"
+version = "0.8.25"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "af310deaae937e48a26602b730250b4949e125f468f11e6990be3e5304ddd96f"
+checksum = "c5b940ebc25896e71dd073bad2dbaa2abfe97b0a391415e22ad1326d9c54e3c4"
 
 [[package]]
 name = "xmltree"
@@ -10542,7 +10756,7 @@ checksum = "2380878cad4ac9aac1e2435f3eb4020e8374b5f13c296cb75b4620ff8e229154"
 dependencies = [
  "proc-macro2",
  "quote",
- "syn 2.0.89",
+ "syn 2.0.96",
  "synstructure",
 ]
 
@@ -10564,7 +10778,7 @@ checksum = "fa4f8080344d4671fb4e831a13ad1e68092748387dfc4f55e356242fae12ce3e"
 dependencies = [
  "proc-macro2",
  "quote",
- "syn 2.0.89",
+ "syn 2.0.96",
 ]
 
 [[package]]
@@ -10584,7 +10798,7 @@ checksum = "595eed982f7d355beb85837f651fa22e90b3c044842dc7f2c2842c086f295808"
 dependencies = [
  "proc-macro2",
  "quote",
- "syn 2.0.89",
+ "syn 2.0.96",
  "synstructure",
 ]
 
@@ -10606,7 +10820,7 @@ checksum = "ce36e65b0d2999d2aafac989fb249189a141aee1f53c612c1f37d72631959f69"
 dependencies = [
  "proc-macro2",
  "quote",
- "syn 2.0.89",
+ "syn 2.0.96",
 ]
 
 [[package]]
@@ -10628,7 +10842,7 @@ checksum = "6eafa6dfb17584ea3e2bd6e76e0cc15ad7af12b09abdd1ca55961bed9b1063c6"
 dependencies = [
  "proc-macro2",
  "quote",
- "syn 2.0.89",
+ "syn 2.0.96",
 ]
 
 [[package]]
diff --git a/Cargo.toml b/Cargo.toml
index 23e52a306b..e30b6aa2b6 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -9,11 +9,13 @@ members = [
     "beacon_node/client",
     "beacon_node/eth1",
     "beacon_node/execution_layer",
+    "beacon_node/genesis",
     "beacon_node/http_api",
     "beacon_node/http_metrics",
     "beacon_node/lighthouse_network",
     "beacon_node/lighthouse_network/gossipsub",
     "beacon_node/network",
+    "beacon_node/operation_pool",
     "beacon_node/store",
     "beacon_node/timer",
 
@@ -30,6 +32,8 @@ members = [
     "common/eth2_interop_keypairs",
     "common/eth2_network_config",
     "common/eth2_wallet_manager",
+    "common/filesystem",
+    "common/health_metrics",
     "common/lighthouse_version",
     "common/lockfile",
     "common/logging",
@@ -48,14 +52,16 @@ members = [
     "common/unused_port",
     "common/validator_dir",
     "common/warp_utils",
+
     "consensus/fixed_bytes",
     "consensus/fork_choice",
-
     "consensus/int_to_bytes",
+    "consensus/merkle_proof",
     "consensus/proto_array",
     "consensus/safe_arith",
     "consensus/state_processing",
     "consensus/swap_or_not_shuffle",
+    "consensus/types",
 
     "crypto/bls",
     "crypto/eth2_key_derivation",
@@ -247,6 +253,7 @@ filesystem = { path = "common/filesystem" }
 fork_choice = { path = "consensus/fork_choice" }
 genesis = { path = "beacon_node/genesis" }
 gossipsub = { path = "beacon_node/lighthouse_network/gossipsub/" }
+health_metrics = { path = "common/health_metrics" }
 http_api = { path = "beacon_node/http_api" }
 initialized_validators = { path = "validator_client/initialized_validators" }
 int_to_bytes = { path = "consensus/int_to_bytes" }
diff --git a/Cross.toml b/Cross.toml
index 871391253d..8181967f32 100644
--- a/Cross.toml
+++ b/Cross.toml
@@ -3,3 +3,14 @@ pre-build = ["apt-get install -y cmake clang-5.0"]
 
 [target.aarch64-unknown-linux-gnu]
 pre-build = ["apt-get install -y cmake clang-5.0"]
+
+# Allow setting page size limits for jemalloc at build time:
+# For certain architectures (like aarch64), we must compile
+# jemalloc with support for large page sizes, otherwise the host's
+# system page size will be used, which may not work on the target systems.
+# JEMALLOC_SYS_WITH_LG_PAGE=16 tells jemalloc to support up to 64-KiB
+# pages. See: https://github.com/sigp/lighthouse/issues/5244
+[build.env]
+passthrough = [
+    "JEMALLOC_SYS_WITH_LG_PAGE",
+]
diff --git a/Dockerfile b/Dockerfile
index 0f334e2ac8..437c864c30 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -1,4 +1,4 @@
-FROM rust:1.80.0-bullseye AS builder
+FROM rust:1.84.0-bullseye AS builder
 RUN apt-get update && apt-get -y upgrade && apt-get install -y cmake libclang-dev
 COPY . lighthouse
 ARG FEATURES
diff --git a/Makefile b/Makefile
index 8faf8a2e54..81477634fe 100644
--- a/Makefile
+++ b/Makefile
@@ -14,7 +14,7 @@ BUILD_PATH_AARCH64 = "target/$(AARCH64_TAG)/release"
 PINNED_NIGHTLY ?= nightly
 
 # List of features to use when cross-compiling. Can be overridden via the environment.
-CROSS_FEATURES ?= gnosis,slasher-lmdb,slasher-mdbx,slasher-redb,jemalloc
+CROSS_FEATURES ?= gnosis,slasher-lmdb,slasher-mdbx,slasher-redb,jemalloc,beacon-node-leveldb,beacon-node-redb
 
 # Cargo profile for Cross builds. Default is for local builds, CI uses an override.
 CROSS_PROFILE ?= release
@@ -30,7 +30,7 @@ PROFILE ?= release
 
 # List of all hard forks. This list is used to set env variables for several tests so that
 # they run for different forks.
-FORKS=phase0 altair bellatrix capella deneb electra
+FORKS=phase0 altair bellatrix capella deneb electra fulu
 
 # Extra flags for Cargo
 CARGO_INSTALL_EXTRA_FLAGS?=
@@ -63,12 +63,18 @@ install-lcli:
 build-x86_64:
 	cross build --bin lighthouse --target x86_64-unknown-linux-gnu --features "portable,$(CROSS_FEATURES)" --profile "$(CROSS_PROFILE)" --locked
 build-aarch64:
-	cross build --bin lighthouse --target aarch64-unknown-linux-gnu --features "portable,$(CROSS_FEATURES)" --profile "$(CROSS_PROFILE)" --locked
+	# JEMALLOC_SYS_WITH_LG_PAGE=16 tells jemalloc to support up to 64-KiB
+	# pages, which are commonly used by aarch64 systems.
+	# See: https://github.com/sigp/lighthouse/issues/5244
+	JEMALLOC_SYS_WITH_LG_PAGE=16 cross build --bin lighthouse --target aarch64-unknown-linux-gnu --features "portable,$(CROSS_FEATURES)" --profile "$(CROSS_PROFILE)" --locked
 
 build-lcli-x86_64:
 	cross build --bin lcli --target x86_64-unknown-linux-gnu --features "portable" --profile "$(CROSS_PROFILE)" --locked
 build-lcli-aarch64:
-	cross build --bin lcli --target aarch64-unknown-linux-gnu --features "portable" --profile "$(CROSS_PROFILE)" --locked
+	# JEMALLOC_SYS_WITH_LG_PAGE=16 tells jemalloc to support up to 64-KiB
+	# pages, which are commonly used by aarch64 systems.
+	# See: https://github.com/sigp/lighthouse/issues/5244
+	JEMALLOC_SYS_WITH_LG_PAGE=16 cross build --bin lcli --target aarch64-unknown-linux-gnu --features "portable" --profile "$(CROSS_PROFILE)" --locked
 
 # Create a `.tar.gz` containing a binary for a specific target.
 define tarball_release_binary
@@ -222,7 +228,7 @@ lint-fix:
 
 # Also run the lints on the optimized-only tests
 lint-full:
-	RUSTFLAGS="-C debug-assertions=no $(RUSTFLAGS)" $(MAKE) lint
+	TEST_FEATURES="beacon-node-leveldb,beacon-node-redb,${TEST_FEATURES}"  RUSTFLAGS="-C debug-assertions=no $(RUSTFLAGS)" $(MAKE) lint
 
 # Runs the makefile in the `ef_tests` repo.
 #
diff --git a/account_manager/src/validator/create.rs b/account_manager/src/validator/create.rs
index 73e0ad54d4..3db8c3f152 100644
--- a/account_manager/src/validator/create.rs
+++ b/account_manager/src/validator/create.rs
@@ -6,14 +6,13 @@ use account_utils::{
 };
 use clap::{Arg, ArgAction, ArgMatches, Command};
 use clap_utils::FLAG_HEADER;
-use directory::{
-    ensure_dir_exists, parse_path_or_default_with_flag, DEFAULT_SECRET_DIR, DEFAULT_WALLET_DIR,
-};
+use directory::{parse_path_or_default_with_flag, DEFAULT_SECRET_DIR, DEFAULT_WALLET_DIR};
 use environment::Environment;
 use eth2_wallet_manager::WalletManager;
 use slashing_protection::{SlashingDatabase, SLASHING_PROTECTION_FILENAME};
 use std::ffi::OsStr;
 use std::fs;
+use std::fs::create_dir_all;
 use std::path::{Path, PathBuf};
 use types::EthSpec;
 use validator_dir::Builder as ValidatorDirBuilder;
@@ -156,8 +155,10 @@ pub fn cli_run<E: EthSpec>(
         ));
     }
 
-    ensure_dir_exists(&validator_dir)?;
-    ensure_dir_exists(&secrets_dir)?;
+    create_dir_all(&validator_dir)
+        .map_err(|e| format!("Could not create validator dir at {validator_dir:?}: {e:?}"))?;
+    create_dir_all(&secrets_dir)
+        .map_err(|e| format!("Could not create secrets dir at {secrets_dir:?}: {e:?}"))?;
 
     eprintln!("secrets-dir path {:?}", secrets_dir);
     eprintln!("wallets-dir path {:?}", wallet_base_dir);
diff --git a/account_manager/src/validator/recover.rs b/account_manager/src/validator/recover.rs
index ddf754edac..19d161a468 100644
--- a/account_manager/src/validator/recover.rs
+++ b/account_manager/src/validator/recover.rs
@@ -5,10 +5,10 @@ use account_utils::eth2_keystore::{keypair_from_secret, Keystore, KeystoreBuilde
 use account_utils::{random_password, read_mnemonic_from_cli, STDIN_INPUTS_FLAG};
 use clap::{Arg, ArgAction, ArgMatches, Command};
 use clap_utils::FLAG_HEADER;
-use directory::ensure_dir_exists;
 use directory::{parse_path_or_default_with_flag, DEFAULT_SECRET_DIR};
 use eth2_wallet::bip39::Seed;
 use eth2_wallet::{recover_validator_secret_from_mnemonic, KeyType, ValidatorKeystores};
+use std::fs::create_dir_all;
 use std::path::PathBuf;
 use validator_dir::Builder as ValidatorDirBuilder;
 pub const CMD: &str = "recover";
@@ -91,8 +91,10 @@ pub fn cli_run(matches: &ArgMatches, validator_dir: PathBuf) -> Result<(), Strin
 
     eprintln!("secrets-dir path: {:?}", secrets_dir);
 
-    ensure_dir_exists(&validator_dir)?;
-    ensure_dir_exists(&secrets_dir)?;
+    create_dir_all(&validator_dir)
+        .map_err(|e| format!("Could not create validator dir at {validator_dir:?}: {e:?}"))?;
+    create_dir_all(&secrets_dir)
+        .map_err(|e| format!("Could not create secrets dir at {secrets_dir:?}: {e:?}"))?;
 
     eprintln!();
     eprintln!("WARNING: KEY RECOVERY CAN LEAD TO DUPLICATING VALIDATORS KEYS, WHICH CAN LEAD TO SLASHING.");
diff --git a/account_manager/src/wallet/mod.rs b/account_manager/src/wallet/mod.rs
index 020858db77..c34f0363a4 100644
--- a/account_manager/src/wallet/mod.rs
+++ b/account_manager/src/wallet/mod.rs
@@ -5,7 +5,8 @@ pub mod recover;
 use crate::WALLETS_DIR_FLAG;
 use clap::{Arg, ArgAction, ArgMatches, Command};
 use clap_utils::FLAG_HEADER;
-use directory::{ensure_dir_exists, parse_path_or_default_with_flag, DEFAULT_WALLET_DIR};
+use directory::{parse_path_or_default_with_flag, DEFAULT_WALLET_DIR};
+use std::fs::create_dir_all;
 use std::path::PathBuf;
 
 pub const CMD: &str = "wallet";
@@ -44,7 +45,7 @@ pub fn cli_run(matches: &ArgMatches) -> Result<(), String> {
     } else {
         parse_path_or_default_with_flag(matches, WALLETS_DIR_FLAG, DEFAULT_WALLET_DIR)?
     };
-    ensure_dir_exists(&wallet_base_dir)?;
+    create_dir_all(&wallet_base_dir).map_err(|_| "Could not create wallet base dir")?;
 
     eprintln!("wallet-dir path: {:?}", wallet_base_dir);
 
diff --git a/beacon_node/beacon_chain/src/attestation_rewards.rs b/beacon_node/beacon_chain/src/attestation_rewards.rs
index 87b7384ea6..3b37b09e40 100644
--- a/beacon_node/beacon_chain/src/attestation_rewards.rs
+++ b/beacon_node/beacon_chain/src/attestation_rewards.rs
@@ -51,13 +51,10 @@ impl<T: BeaconChainTypes> BeaconChain<T> {
             .get_state(&state_root, Some(state_slot))?
             .ok_or(BeaconChainError::MissingBeaconState(state_root))?;
 
-        match state {
-            BeaconState::Base(_) => self.compute_attestation_rewards_base(state, validators),
-            BeaconState::Altair(_)
-            | BeaconState::Bellatrix(_)
-            | BeaconState::Capella(_)
-            | BeaconState::Deneb(_)
-            | BeaconState::Electra(_) => self.compute_attestation_rewards_altair(state, validators),
+        if state.fork_name_unchecked().altair_enabled() {
+            self.compute_attestation_rewards_altair(state, validators)
+        } else {
+            self.compute_attestation_rewards_base(state, validators)
         }
     }
 
diff --git a/beacon_node/beacon_chain/src/attestation_verification.rs b/beacon_node/beacon_chain/src/attestation_verification.rs
index c3dea3dbb4..a69eb99a51 100644
--- a/beacon_node/beacon_chain/src/attestation_verification.rs
+++ b/beacon_node/beacon_chain/src/attestation_verification.rs
@@ -62,7 +62,7 @@ use tree_hash::TreeHash;
 use types::{
     Attestation, AttestationRef, BeaconCommittee, BeaconStateError::NoCommitteeFound, ChainSpec,
     CommitteeIndex, Epoch, EthSpec, Hash256, IndexedAttestation, SelectionProof,
-    SignedAggregateAndProof, Slot, SubnetId,
+    SignedAggregateAndProof, SingleAttestation, Slot, SubnetId,
 };
 
 pub use batch::{batch_verify_aggregated_attestations, batch_verify_unaggregated_attestations};
@@ -317,12 +317,22 @@ pub struct VerifiedUnaggregatedAttestation<'a, T: BeaconChainTypes> {
     attestation: AttestationRef<'a, T::EthSpec>,
     indexed_attestation: IndexedAttestation<T::EthSpec>,
     subnet_id: SubnetId,
+    validator_index: usize,
 }
 
 impl<T: BeaconChainTypes> VerifiedUnaggregatedAttestation<'_, T> {
     pub fn into_indexed_attestation(self) -> IndexedAttestation<T::EthSpec> {
         self.indexed_attestation
     }
+
+    pub fn single_attestation(&self) -> Option<SingleAttestation> {
+        Some(SingleAttestation {
+            committee_index: self.attestation.committee_index()?,
+            attester_index: self.validator_index as u64,
+            data: self.attestation.data().clone(),
+            signature: self.attestation.signature().clone(),
+        })
+    }
 }
 
 /// Custom `Clone` implementation is to avoid the restrictive trait bounds applied by the usual derive
@@ -1035,6 +1045,7 @@ impl<'a, T: BeaconChainTypes> VerifiedUnaggregatedAttestation<'a, T> {
             attestation,
             indexed_attestation,
             subnet_id,
+            validator_index: validator_index as usize,
         })
     }
 
diff --git a/beacon_node/beacon_chain/src/beacon_block_streamer.rs b/beacon_node/beacon_chain/src/beacon_block_streamer.rs
index b76dba88fd..32ec776868 100644
--- a/beacon_node/beacon_chain/src/beacon_block_streamer.rs
+++ b/beacon_node/beacon_chain/src/beacon_block_streamer.rs
@@ -15,7 +15,7 @@ use types::{
 };
 use types::{
     ExecutionPayload, ExecutionPayloadBellatrix, ExecutionPayloadCapella, ExecutionPayloadElectra,
-    ExecutionPayloadHeader,
+    ExecutionPayloadFulu, ExecutionPayloadHeader,
 };
 
 #[derive(PartialEq)]
@@ -99,6 +99,7 @@ fn reconstruct_default_header_block<E: EthSpec>(
         ForkName::Capella => ExecutionPayloadCapella::default().into(),
         ForkName::Deneb => ExecutionPayloadDeneb::default().into(),
         ForkName::Electra => ExecutionPayloadElectra::default().into(),
+        ForkName::Fulu => ExecutionPayloadFulu::default().into(),
         ForkName::Base | ForkName::Altair => {
             return Err(Error::PayloadReconstruction(format!(
                 "Block with fork variant {} has execution payload",
@@ -742,13 +743,14 @@ mod tests {
     }
 
     #[tokio::test]
-    async fn check_all_blocks_from_altair_to_electra() {
+    async fn check_all_blocks_from_altair_to_fulu() {
         let slots_per_epoch = MinimalEthSpec::slots_per_epoch() as usize;
-        let num_epochs = 10;
+        let num_epochs = 12;
         let bellatrix_fork_epoch = 2usize;
         let capella_fork_epoch = 4usize;
         let deneb_fork_epoch = 6usize;
         let electra_fork_epoch = 8usize;
+        let fulu_fork_epoch = 10usize;
         let num_blocks_produced = num_epochs * slots_per_epoch;
 
         let mut spec = test_spec::<MinimalEthSpec>();
@@ -757,6 +759,7 @@ mod tests {
         spec.capella_fork_epoch = Some(Epoch::new(capella_fork_epoch as u64));
         spec.deneb_fork_epoch = Some(Epoch::new(deneb_fork_epoch as u64));
         spec.electra_fork_epoch = Some(Epoch::new(electra_fork_epoch as u64));
+        spec.fulu_fork_epoch = Some(Epoch::new(fulu_fork_epoch as u64));
         let spec = Arc::new(spec);
 
         let harness = get_harness(VALIDATOR_COUNT, spec.clone());
diff --git a/beacon_node/beacon_chain/src/beacon_chain.rs b/beacon_node/beacon_chain/src/beacon_chain.rs
index 14d902d50f..9f3f06ab8c 100644
--- a/beacon_node/beacon_chain/src/beacon_chain.rs
+++ b/beacon_node/beacon_chain/src/beacon_chain.rs
@@ -34,6 +34,7 @@ use crate::execution_payload::{get_execution_payload, NotifyExecutionLayer, Prep
 use crate::fork_choice_signal::{ForkChoiceSignalRx, ForkChoiceSignalTx, ForkChoiceWaitResult};
 use crate::graffiti_calculator::GraffitiCalculator;
 use crate::head_tracker::{HeadTracker, HeadTrackerReader, SszHeadTracker};
+use crate::kzg_utils::reconstruct_blobs;
 use crate::light_client_finality_update_verification::{
     Error as LightClientFinalityUpdateError, VerifiedLightClientFinalityUpdate,
 };
@@ -117,10 +118,11 @@ use std::sync::Arc;
 use std::time::Duration;
 use store::iter::{BlockRootsIterator, ParentRootBlockIterator, StateRootsIterator};
 use store::{
-    DatabaseBlock, Error as DBError, HotColdDB, KeyValueStore, KeyValueStoreOp, StoreItem, StoreOp,
+    BlobSidecarListFromRoot, DatabaseBlock, Error as DBError, HotColdDB, KeyValueStore,
+    KeyValueStoreOp, StoreItem, StoreOp,
 };
 use task_executor::{ShutdownReason, TaskExecutor};
-use tokio::sync::mpsc::Receiver;
+use tokio::sync::oneshot;
 use tokio_stream::Stream;
 use tree_hash::TreeHash;
 use types::blob_sidecar::FixedBlobSidecarList;
@@ -575,7 +577,7 @@ impl<T: BeaconChainTypes> BeaconChain<T> {
             .start_slot(T::EthSpec::slots_per_epoch());
         let is_canonical = self
             .block_root_at_slot(block_slot, WhenSlotSkipped::None)?
-            .map_or(false, |canonical_root| block_root == &canonical_root);
+            .is_some_and(|canonical_root| block_root == &canonical_root);
         Ok(block_slot <= finalized_slot && is_canonical)
     }
 
@@ -606,7 +608,7 @@ impl<T: BeaconChainTypes> BeaconChain<T> {
         let slot_is_finalized = state_slot <= finalized_slot;
         let canonical = self
             .state_root_at_slot(state_slot)?
-            .map_or(false, |canonical_root| state_root == &canonical_root);
+            .is_some_and(|canonical_root| state_root == &canonical_root);
         Ok(FinalizationAndCanonicity {
             slot_is_finalized,
             canonical,
@@ -1149,9 +1151,10 @@ impl<T: BeaconChainTypes> BeaconChain<T> {
     pub fn get_blobs_checking_early_attester_cache(
         &self,
         block_root: &Hash256,
-    ) -> Result<BlobSidecarList<T::EthSpec>, Error> {
+    ) -> Result<BlobSidecarListFromRoot<T::EthSpec>, Error> {
         self.early_attester_cache
             .get_blobs(*block_root)
+            .map(Into::into)
             .map_or_else(|| self.get_blobs(block_root), Ok)
     }
 
@@ -1242,10 +1245,59 @@ impl<T: BeaconChainTypes> BeaconChain<T> {
     ///
     /// ## Errors
     /// May return a database error.
-    pub fn get_blobs(&self, block_root: &Hash256) -> Result<BlobSidecarList<T::EthSpec>, Error> {
-        match self.store.get_blobs(block_root)? {
-            Some(blobs) => Ok(blobs),
-            None => Ok(BlobSidecarList::default()),
+    pub fn get_blobs(
+        &self,
+        block_root: &Hash256,
+    ) -> Result<BlobSidecarListFromRoot<T::EthSpec>, Error> {
+        self.store.get_blobs(block_root).map_err(Error::from)
+    }
+
+    /// Returns the data columns at the given root, if any.
+    ///
+    /// ## Errors
+    /// May return a database error.
+    pub fn get_data_columns(
+        &self,
+        block_root: &Hash256,
+    ) -> Result<Option<DataColumnSidecarList<T::EthSpec>>, Error> {
+        self.store.get_data_columns(block_root).map_err(Error::from)
+    }
+
+    /// Returns the blobs at the given root, if any.
+    ///
+    /// Uses the `block.epoch()` to determine whether to retrieve blobs or columns from the store.
+    ///
+    /// If at least 50% of columns are retrieved, blobs will be reconstructed and returned,
+    /// otherwise an error `InsufficientColumnsToReconstructBlobs` is returned.
+    ///
+    /// ## Errors
+    /// May return a database error.
+    pub fn get_or_reconstruct_blobs(
+        &self,
+        block_root: &Hash256,
+    ) -> Result<Option<BlobSidecarList<T::EthSpec>>, Error> {
+        let Some(block) = self.store.get_blinded_block(block_root)? else {
+            return Ok(None);
+        };
+
+        if self.spec.is_peer_das_enabled_for_epoch(block.epoch()) {
+            if let Some(columns) = self.store.get_data_columns(block_root)? {
+                let num_required_columns = self.spec.number_of_columns / 2;
+                let reconstruction_possible = columns.len() >= num_required_columns as usize;
+                if reconstruction_possible {
+                    reconstruct_blobs(&self.kzg, &columns, None, &block, &self.spec)
+                        .map(Some)
+                        .map_err(Error::FailedToReconstructBlobs)
+                } else {
+                    Err(Error::InsufficientColumnsToReconstructBlobs {
+                        columns_found: columns.len(),
+                    })
+                }
+            } else {
+                Ok(None)
+            }
+        } else {
+            self.get_blobs(block_root).map(|b| b.blobs())
         }
     }
 
@@ -2161,10 +2213,30 @@ impl<T: BeaconChainTypes> BeaconChain<T> {
             |v| {
                 // This method is called for API and gossip attestations, so this covers all unaggregated attestation events
                 if let Some(event_handler) = self.event_handler.as_ref() {
+                    if event_handler.has_single_attestation_subscribers() {
+                        let current_fork = self
+                            .spec
+                            .fork_name_at_slot::<T::EthSpec>(v.attestation().data().slot);
+                        if current_fork.electra_enabled() {
+                            // I don't see a situation where this could return None. The upstream unaggregated attestation checks
+                            // should have already verified that this is an attestation with a single committee bit set.
+                            if let Some(single_attestation) = v.single_attestation() {
+                                event_handler.register(EventKind::SingleAttestation(Box::new(
+                                    single_attestation,
+                                )));
+                            }
+                        }
+                    }
+
                     if event_handler.has_attestation_subscribers() {
-                        event_handler.register(EventKind::Attestation(Box::new(
-                            v.attestation().clone_as_attestation(),
-                        )));
+                        let current_fork = self
+                            .spec
+                            .fork_name_at_slot::<T::EthSpec>(v.attestation().data().slot);
+                        if !current_fork.electra_enabled() {
+                            event_handler.register(EventKind::Attestation(Box::new(
+                                v.attestation().clone_as_attestation(),
+                            )));
+                        }
                     }
                 }
                 metrics::inc_counter(&metrics::UNAGGREGATED_ATTESTATION_PROCESSING_SUCCESSES);
@@ -3214,7 +3286,7 @@ impl<T: BeaconChainTypes> BeaconChain<T> {
         slot: Slot,
         block_root: Hash256,
         blobs: FixedBlobSidecarList<T::EthSpec>,
-        data_column_recv: Option<Receiver<DataColumnSidecarList<T::EthSpec>>>,
+        data_column_recv: Option<oneshot::Receiver<DataColumnSidecarList<T::EthSpec>>>,
     ) -> Result<AvailabilityProcessingStatus, BlockError> {
         // If this block has already been imported to forkchoice it must have been available, so
         // we don't need to process its blobs again.
@@ -3342,7 +3414,7 @@ impl<T: BeaconChainTypes> BeaconChain<T> {
                 };
 
                 let r = self
-                    .process_availability(slot, availability, None, || Ok(()))
+                    .process_availability(slot, availability, || Ok(()))
                     .await;
                 self.remove_notified(&block_root, r)
                     .map(|availability_processing_status| {
@@ -3470,7 +3542,7 @@ impl<T: BeaconChainTypes> BeaconChain<T> {
 
             match executed_block {
                 ExecutedBlock::Available(block) => {
-                    self.import_available_block(Box::new(block), None).await
+                    self.import_available_block(Box::new(block)).await
                 }
                 ExecutedBlock::AvailabilityPending(block) => {
                     self.check_block_availability_and_import(block).await
@@ -3602,7 +3674,7 @@ impl<T: BeaconChainTypes> BeaconChain<T> {
         let availability = self
             .data_availability_checker
             .put_pending_executed_block(block)?;
-        self.process_availability(slot, availability, None, || Ok(()))
+        self.process_availability(slot, availability, || Ok(()))
             .await
     }
 
@@ -3618,7 +3690,7 @@ impl<T: BeaconChainTypes> BeaconChain<T> {
         }
         let availability = self.data_availability_checker.put_gossip_blob(blob)?;
 
-        self.process_availability(slot, availability, None, || Ok(()))
+        self.process_availability(slot, availability, || Ok(()))
             .await
     }
 
@@ -3641,7 +3713,7 @@ impl<T: BeaconChainTypes> BeaconChain<T> {
             .data_availability_checker
             .put_gossip_data_columns(block_root, data_columns)?;
 
-        self.process_availability(slot, availability, None, publish_fn)
+        self.process_availability(slot, availability, publish_fn)
             .await
     }
 
@@ -3685,7 +3757,7 @@ impl<T: BeaconChainTypes> BeaconChain<T> {
             .data_availability_checker
             .put_rpc_blobs(block_root, blobs)?;
 
-        self.process_availability(slot, availability, None, || Ok(()))
+        self.process_availability(slot, availability, || Ok(()))
             .await
     }
 
@@ -3694,14 +3766,14 @@ impl<T: BeaconChainTypes> BeaconChain<T> {
         slot: Slot,
         block_root: Hash256,
         blobs: FixedBlobSidecarList<T::EthSpec>,
-        data_column_recv: Option<Receiver<DataColumnSidecarList<T::EthSpec>>>,
+        data_column_recv: Option<oneshot::Receiver<DataColumnSidecarList<T::EthSpec>>>,
     ) -> Result<AvailabilityProcessingStatus, BlockError> {
         self.check_blobs_for_slashability(block_root, &blobs)?;
-        let availability = self
-            .data_availability_checker
-            .put_engine_blobs(block_root, blobs)?;
+        let availability =
+            self.data_availability_checker
+                .put_engine_blobs(block_root, blobs, data_column_recv)?;
 
-        self.process_availability(slot, availability, data_column_recv, || Ok(()))
+        self.process_availability(slot, availability, || Ok(()))
             .await
     }
 
@@ -3741,7 +3813,7 @@ impl<T: BeaconChainTypes> BeaconChain<T> {
             .data_availability_checker
             .put_rpc_custody_columns(block_root, custody_columns)?;
 
-        self.process_availability(slot, availability, None, || Ok(()))
+        self.process_availability(slot, availability, || Ok(()))
             .await
     }
 
@@ -3753,14 +3825,13 @@ impl<T: BeaconChainTypes> BeaconChain<T> {
         self: &Arc<Self>,
         slot: Slot,
         availability: Availability<T::EthSpec>,
-        recv: Option<Receiver<DataColumnSidecarList<T::EthSpec>>>,
         publish_fn: impl FnOnce() -> Result<(), BlockError>,
     ) -> Result<AvailabilityProcessingStatus, BlockError> {
         match availability {
             Availability::Available(block) => {
                 publish_fn()?;
                 // Block is fully available, import into fork choice
-                self.import_available_block(block, recv).await
+                self.import_available_block(block).await
             }
             Availability::MissingComponents(block_root) => Ok(
                 AvailabilityProcessingStatus::MissingComponents(slot, block_root),
@@ -3771,7 +3842,6 @@ impl<T: BeaconChainTypes> BeaconChain<T> {
     pub async fn import_available_block(
         self: &Arc<Self>,
         block: Box<AvailableExecutedBlock<T::EthSpec>>,
-        data_column_recv: Option<Receiver<DataColumnSidecarList<T::EthSpec>>>,
     ) -> Result<AvailabilityProcessingStatus, BlockError> {
         let AvailableExecutedBlock {
             block,
@@ -3786,6 +3856,7 @@ impl<T: BeaconChainTypes> BeaconChain<T> {
             parent_eth1_finalization_data,
             confirmed_state_roots,
             consensus_context,
+            data_column_recv,
         } = import_data;
 
         // Record the time at which this block's blobs became available.
@@ -3852,7 +3923,7 @@ impl<T: BeaconChainTypes> BeaconChain<T> {
         parent_block: SignedBlindedBeaconBlock<T::EthSpec>,
         parent_eth1_finalization_data: Eth1FinalizationData,
         mut consensus_context: ConsensusContext<T::EthSpec>,
-        data_column_recv: Option<Receiver<DataColumnSidecarList<T::EthSpec>>>,
+        data_column_recv: Option<oneshot::Receiver<DataColumnSidecarList<T::EthSpec>>>,
     ) -> Result<Hash256, BlockError> {
         // ----------------------------- BLOCK NOT YET ATTESTABLE ----------------------------------
         // Everything in this initial section is on the hot path between processing the block and
@@ -4020,44 +4091,32 @@ impl<T: BeaconChainTypes> BeaconChain<T> {
         // end up with blocks in fork choice that are missing from disk.
         // See https://github.com/sigp/lighthouse/issues/2028
         let (_, signed_block, blobs, data_columns) = signed_block.deconstruct();
-        // TODO(das) we currently store all subnet sampled columns. Tracking issue to exclude non
-        // custody columns: https://github.com/sigp/lighthouse/issues/6465
-        let custody_columns_count = self.data_availability_checker.get_sampling_column_count();
-        // if block is made available via blobs, dropped the data columns.
-        let data_columns = data_columns.filter(|columns| columns.len() == custody_columns_count);
 
-        let data_columns = match (data_columns, data_column_recv) {
-            // If the block was made available via custody columns received from gossip / rpc, use them
-            // since we already have them.
-            (Some(columns), _) => Some(columns),
-            // Otherwise, it means blobs were likely available via fetching from EL, in this case we
-            // wait for the data columns to be computed (blocking).
-            (None, Some(mut data_column_recv)) => {
-                let _column_recv_timer =
-                    metrics::start_timer(&metrics::BLOCK_PROCESSING_DATA_COLUMNS_WAIT);
-                // Unable to receive data columns from sender, sender is either dropped or
-                // failed to compute data columns from blobs. We restore fork choice here and
-                // return to avoid inconsistency in database.
-                if let Some(columns) = data_column_recv.blocking_recv() {
-                    Some(columns)
-                } else {
-                    let err_msg = "Did not receive data columns from sender";
-                    error!(
-                        self.log,
-                        "Failed to store data columns into the database";
-                        "msg" => "Restoring fork choice from disk",
-                        "error" => err_msg,
-                    );
-                    return Err(self
-                        .handle_import_block_db_write_error(fork_choice)
-                        .err()
-                        .unwrap_or(BlockError::InternalError(err_msg.to_string())));
-                }
+        match self.get_blobs_or_columns_store_op(
+            block_root,
+            signed_block.epoch(),
+            blobs,
+            data_columns,
+            data_column_recv,
+        ) {
+            Ok(Some(blobs_or_columns_store_op)) => {
+                ops.push(blobs_or_columns_store_op);
             }
-            // No data columns present and compute data columns task was not spawned.
-            // Could either be no blobs in the block or before PeerDAS activation.
-            (None, None) => None,
-        };
+            Ok(None) => {}
+            Err(e) => {
+                error!(
+                    self.log,
+                    "Failed to store data columns into the database";
+                    "msg" => "Restoring fork choice from disk",
+                    "error" => &e,
+                    "block_root" => ?block_root
+                );
+                return Err(self
+                    .handle_import_block_db_write_error(fork_choice)
+                    .err()
+                    .unwrap_or(BlockError::InternalError(e)));
+            }
+        }
 
         let block = signed_block.message();
         let db_write_timer = metrics::start_timer(&metrics::BLOCK_PROCESSING_DB_WRITE);
@@ -4069,30 +4128,6 @@ impl<T: BeaconChainTypes> BeaconChain<T> {
         ops.push(StoreOp::PutBlock(block_root, signed_block.clone()));
         ops.push(StoreOp::PutState(block.state_root(), &state));
 
-        if let Some(blobs) = blobs {
-            if !blobs.is_empty() {
-                debug!(
-                    self.log, "Writing blobs to store";
-                    "block_root" => %block_root,
-                    "count" => blobs.len(),
-                );
-                ops.push(StoreOp::PutBlobs(block_root, blobs));
-            }
-        }
-
-        if let Some(data_columns) = data_columns {
-            // TODO(das): `available_block includes all sampled columns, but we only need to store
-            // custody columns. To be clarified in spec.
-            if !data_columns.is_empty() {
-                debug!(
-                    self.log, "Writing data_columns to store";
-                    "block_root" => %block_root,
-                    "count" => data_columns.len(),
-                );
-                ops.push(StoreOp::PutDataColumns(block_root, data_columns));
-            }
-        }
-
         let txn_lock = self.store.hot_db.begin_rw_transaction();
 
         if let Err(e) = self.store.do_atomically_with_block_and_blobs_cache(ops) {
@@ -5246,9 +5281,9 @@ impl<T: BeaconChainTypes> BeaconChain<T> {
                 .start_of(slot)
                 .unwrap_or_else(|| Duration::from_secs(0)),
         );
-        block_delays.observed.map_or(false, |delay| {
-            delay >= self.slot_clock.unagg_attestation_production_delay()
-        })
+        block_delays
+            .observed
+            .is_some_and(|delay| delay >= self.slot_clock.unagg_attestation_production_delay())
     }
 
     /// Produce a block for some `slot` upon the given `state`.
@@ -5445,23 +5480,19 @@ impl<T: BeaconChainTypes> BeaconChain<T> {
 
         // If required, start the process of loading an execution payload from the EL early. This
         // allows it to run concurrently with things like attestation packing.
-        let prepare_payload_handle = match &state {
-            BeaconState::Base(_) | BeaconState::Altair(_) => None,
-            BeaconState::Bellatrix(_)
-            | BeaconState::Capella(_)
-            | BeaconState::Deneb(_)
-            | BeaconState::Electra(_) => {
-                let prepare_payload_handle = get_execution_payload(
-                    self.clone(),
-                    &state,
-                    parent_root,
-                    proposer_index,
-                    builder_params,
-                    builder_boost_factor,
-                    block_production_version,
-                )?;
-                Some(prepare_payload_handle)
-            }
+        let prepare_payload_handle = if state.fork_name_unchecked().bellatrix_enabled() {
+            let prepare_payload_handle = get_execution_payload(
+                self.clone(),
+                &state,
+                parent_root,
+                proposer_index,
+                builder_params,
+                builder_boost_factor,
+                block_production_version,
+            )?;
+            Some(prepare_payload_handle)
+        } else {
+            None
         };
 
         let (mut proposer_slashings, mut attester_slashings, mut voluntary_exits) =
@@ -5879,6 +5910,48 @@ impl<T: BeaconChainTypes> BeaconChain<T> {
                     execution_payload_value,
                 )
             }
+            BeaconState::Fulu(_) => {
+                let (
+                    payload,
+                    kzg_commitments,
+                    maybe_blobs_and_proofs,
+                    maybe_requests,
+                    execution_payload_value,
+                ) = block_contents
+                    .ok_or(BlockProductionError::MissingExecutionPayload)?
+                    .deconstruct();
+
+                (
+                    BeaconBlock::Fulu(BeaconBlockFulu {
+                        slot,
+                        proposer_index,
+                        parent_root,
+                        state_root: Hash256::zero(),
+                        body: BeaconBlockBodyFulu {
+                            randao_reveal,
+                            eth1_data,
+                            graffiti,
+                            proposer_slashings: proposer_slashings.into(),
+                            attester_slashings: attester_slashings_electra.into(),
+                            attestations: attestations_electra.into(),
+                            deposits: deposits.into(),
+                            voluntary_exits: voluntary_exits.into(),
+                            sync_aggregate: sync_aggregate
+                                .ok_or(BlockProductionError::MissingSyncAggregate)?,
+                            execution_payload: payload
+                                .try_into()
+                                .map_err(|_| BlockProductionError::InvalidPayloadFork)?,
+                            bls_to_execution_changes: bls_to_execution_changes.into(),
+                            blob_kzg_commitments: kzg_commitments
+                                .ok_or(BlockProductionError::InvalidPayloadFork)?,
+                            execution_requests: maybe_requests
+                                .ok_or(BlockProductionError::MissingExecutionRequests)?,
+                        },
+                    }),
+                    maybe_blobs_and_proofs,
+                    execution_payload_value,
+                )
+            }
         };
 
         let block = SignedBeaconBlock::from_block(
@@ -5955,6 +6028,7 @@ impl<T: BeaconChainTypes> BeaconChain<T> {
 
                 let kzg = self.kzg.as_ref();
 
+                // TODO(fulu): we no longer need blob proofs from PeerDAS and could avoid computing.
                 kzg_utils::validate_blobs::<T::EthSpec>(
                     kzg,
                     expected_kzg_commitments,
@@ -7307,6 +7381,68 @@ impl<T: BeaconChainTypes> BeaconChain<T> {
             reqresp_pre_import_cache_len: self.reqresp_pre_import_cache.read().len(),
         }
     }
+
+    fn get_blobs_or_columns_store_op(
+        &self,
+        block_root: Hash256,
+        block_epoch: Epoch,
+        blobs: Option<BlobSidecarList<T::EthSpec>>,
+        data_columns: Option<DataColumnSidecarList<T::EthSpec>>,
+        data_column_recv: Option<oneshot::Receiver<DataColumnSidecarList<T::EthSpec>>>,
+    ) -> Result<Option<StoreOp<T::EthSpec>>, String> {
+        if self.spec.is_peer_das_enabled_for_epoch(block_epoch) {
+            // TODO(das) we currently store all subnet sampled columns. Tracking issue to exclude non
+            // custody columns: https://github.com/sigp/lighthouse/issues/6465
+            let custody_columns_count = self.data_availability_checker.get_sampling_column_count();
+
+            let custody_columns_available = data_columns
+                .as_ref()
+                .as_ref()
+                .is_some_and(|columns| columns.len() == custody_columns_count);
+
+            let data_columns_to_persist = if custody_columns_available {
+                // If the block was made available via custody columns received from gossip / rpc, use them
+                // since we already have them.
+                data_columns
+            } else if let Some(data_column_recv) = data_column_recv {
+                // Blobs were available from the EL, in this case we wait for the data columns to be computed (blocking).
+                let _column_recv_timer =
+                    metrics::start_timer(&metrics::BLOCK_PROCESSING_DATA_COLUMNS_WAIT);
+                // Unable to receive data columns from sender, sender is either dropped or
+                // failed to compute data columns from blobs. We restore fork choice here and
+                // return to avoid inconsistency in database.
+                let computed_data_columns = data_column_recv
+                    .blocking_recv()
+                    .map_err(|e| format!("Did not receive data columns from sender: {e:?}"))?;
+                Some(computed_data_columns)
+            } else {
+                // No blobs in the block.
+                None
+            };
+
+            if let Some(data_columns) = data_columns_to_persist {
+                if !data_columns.is_empty() {
+                    debug!(
+                        self.log, "Writing data_columns to store";
+                        "block_root" => %block_root,
+                        "count" => data_columns.len(),
+                    );
+                    return Ok(Some(StoreOp::PutDataColumns(block_root, data_columns)));
+                }
+            }
+        } else if let Some(blobs) = blobs {
+            if !blobs.is_empty() {
+                debug!(
+                    self.log, "Writing blobs to store";
+                    "block_root" => %block_root,
+                    "count" => blobs.len(),
+                );
+                return Ok(Some(StoreOp::PutBlobs(block_root, blobs)));
+            }
+        }
+
+        Ok(None)
+    }
 }
 
 impl<T: BeaconChainTypes> Drop for BeaconChain<T> {
diff --git a/beacon_node/beacon_chain/src/blob_verification.rs b/beacon_node/beacon_chain/src/blob_verification.rs
index 6c87deb826..786b627bb7 100644
--- a/beacon_node/beacon_chain/src/blob_verification.rs
+++ b/beacon_node/beacon_chain/src/blob_verification.rs
@@ -400,7 +400,7 @@ pub fn validate_blob_sidecar_for_gossip<T: BeaconChainTypes, O: ObservationStrat
     // since we only subscribe to `MaxBlobsPerBlock` subnets over gossip network.
     // We include this check only for completeness.
     // Getting this error would imply something very wrong with our networking decoding logic.
-    if blob_index >= T::EthSpec::max_blobs_per_block() as u64 {
+    if blob_index >= chain.spec.max_blobs_per_block(blob_epoch) {
         return Err(GossipBlobError::InvalidSubnet {
             expected: subnet,
             received: blob_index,
diff --git a/beacon_node/beacon_chain/src/block_verification.rs b/beacon_node/beacon_chain/src/block_verification.rs
index ddb7bb614a..1265276376 100644
--- a/beacon_node/beacon_chain/src/block_verification.rs
+++ b/beacon_node/beacon_chain/src/block_verification.rs
@@ -208,24 +208,18 @@ pub enum BlockError {
     ///
     /// The block is invalid and the peer is faulty.
     IncorrectBlockProposer { block: u64, local_shuffling: u64 },
-    /// The proposal signature in invalid.
-    ///
-    /// ## Peer scoring
-    ///
-    /// The block is invalid and the peer is faulty.
-    ProposalSignatureInvalid,
     /// The `block.proposal_index` is not known.
     ///
     /// ## Peer scoring
     ///
     /// The block is invalid and the peer is faulty.
     UnknownValidator(u64),
-    /// A signature in the block is invalid (exactly which is unknown).
+    /// A signature in the block is invalid
     ///
     /// ## Peer scoring
     ///
     /// The block is invalid and the peer is faulty.
-    InvalidSignature,
+    InvalidSignature(InvalidSignature),
     /// The provided block is not from a later slot than its parent.
     ///
     /// ## Peer scoring
@@ -329,6 +323,17 @@ pub enum BlockError {
     InternalError(String),
 }
 
+/// Which specific signature(s) are invalid in a SignedBeaconBlock
+#[derive(Debug)]
+pub enum InvalidSignature {
+    // The outer signature in a SignedBeaconBlock
+    ProposerSignature,
+    // One or more signatures in BeaconBlockBody
+    BlockBodySignatures,
+    // One or more signatures in SignedBeaconBlock
+    Unknown,
+}
+
 impl From<AvailabilityCheckError> for BlockError {
     fn from(e: AvailabilityCheckError) -> Self {
         Self::AvailabilityCheck(e)
@@ -523,7 +528,9 @@ pub enum BlockSlashInfo<TErr> {
 impl BlockSlashInfo<BlockError> {
     pub fn from_early_error_block(header: SignedBeaconBlockHeader, e: BlockError) -> Self {
         match e {
-            BlockError::ProposalSignatureInvalid => BlockSlashInfo::SignatureInvalid(e),
+            BlockError::InvalidSignature(InvalidSignature::ProposerSignature) => {
+                BlockSlashInfo::SignatureInvalid(e)
+            }
             // `InvalidSignature` could indicate any signature in the block, so we want
             // to recheck the proposer signature alone.
             _ => BlockSlashInfo::SignatureNotChecked(header, e),
@@ -652,7 +659,7 @@ pub fn signature_verify_chain_segment<T: BeaconChainTypes>(
     }
 
     if signature_verifier.verify().is_err() {
-        return Err(BlockError::InvalidSignature);
+        return Err(BlockError::InvalidSignature(InvalidSignature::Unknown));
     }
 
     drop(pubkey_cache);
@@ -964,7 +971,9 @@ impl<T: BeaconChainTypes> GossipVerifiedBlock<T> {
         };
 
         if !signature_is_valid {
-            return Err(BlockError::ProposalSignatureInvalid);
+            return Err(BlockError::InvalidSignature(
+                InvalidSignature::ProposerSignature,
+            ));
         }
 
         chain
@@ -1098,7 +1107,26 @@ impl<T: BeaconChainTypes> SignatureVerifiedBlock<T> {
                 parent: Some(parent),
             })
         } else {
-            Err(BlockError::InvalidSignature)
+            // Re-verify the proposer signature in isolation to attribute fault
+            let pubkey = pubkey_cache
+                .get(block.message().proposer_index() as usize)
+                .ok_or_else(|| BlockError::UnknownValidator(block.message().proposer_index()))?;
+            if block.as_block().verify_signature(
+                Some(block_root),
+                pubkey,
+                &state.fork(),
+                chain.genesis_validators_root,
+                &chain.spec,
+            ) {
+                // Proposer signature is valid, the invalid signature must be in the body
+                Err(BlockError::InvalidSignature(
+                    InvalidSignature::BlockBodySignatures,
+                ))
+            } else {
+                Err(BlockError::InvalidSignature(
+                    InvalidSignature::ProposerSignature,
+                ))
+            }
         }
     }
 
@@ -1153,7 +1181,9 @@ impl<T: BeaconChainTypes> SignatureVerifiedBlock<T> {
                 consensus_context,
             })
         } else {
-            Err(BlockError::InvalidSignature)
+            Err(BlockError::InvalidSignature(
+                InvalidSignature::BlockBodySignatures,
+            ))
         }
     }
 
@@ -1677,6 +1707,7 @@ impl<T: BeaconChainTypes> ExecutionPendingBlock<T> {
                 parent_eth1_finalization_data,
                 confirmed_state_roots,
                 consensus_context,
+                data_column_recv: None,
             },
             payload_verification_handle,
         })
@@ -1980,7 +2011,7 @@ impl BlockBlobError for BlockError {
     }
 
     fn proposer_signature_invalid() -> Self {
-        BlockError::ProposalSignatureInvalid
+        BlockError::InvalidSignature(InvalidSignature::ProposerSignature)
     }
 }
 
diff --git a/beacon_node/beacon_chain/src/block_verification_types.rs b/beacon_node/beacon_chain/src/block_verification_types.rs
index 420c83081c..38d0fc708c 100644
--- a/beacon_node/beacon_chain/src/block_verification_types.rs
+++ b/beacon_node/beacon_chain/src/block_verification_types.rs
@@ -4,14 +4,14 @@ use crate::data_column_verification::{CustodyDataColumn, CustodyDataColumnList};
 use crate::eth1_finalization_cache::Eth1FinalizationData;
 use crate::{get_block_root, PayloadVerificationOutcome};
 use derivative::Derivative;
-use ssz_types::VariableList;
 use state_processing::ConsensusContext;
 use std::fmt::{Debug, Formatter};
 use std::sync::Arc;
-use types::blob_sidecar::{BlobIdentifier, FixedBlobSidecarList};
+use tokio::sync::oneshot;
+use types::blob_sidecar::BlobIdentifier;
 use types::{
-    BeaconBlockRef, BeaconState, BlindedPayload, BlobSidecarList, ChainSpec, Epoch, EthSpec,
-    Hash256, RuntimeVariableList, SignedBeaconBlock, SignedBeaconBlockHeader, Slot,
+    BeaconBlockRef, BeaconState, BlindedPayload, BlobSidecarList, ChainSpec, DataColumnSidecarList,
+    Epoch, EthSpec, Hash256, RuntimeVariableList, SignedBeaconBlock, SignedBeaconBlockHeader, Slot,
 };
 
 /// A block that has been received over RPC. It has 2 internal variants:
@@ -165,7 +165,7 @@ impl<E: EthSpec> RpcBlock<E> {
         let inner = if !custody_columns.is_empty() {
             RpcBlockInner::BlockAndCustodyColumns(
                 block,
-                RuntimeVariableList::new(custody_columns, spec.number_of_columns)?,
+                RuntimeVariableList::new(custody_columns, spec.number_of_columns as usize)?,
             )
         } else {
             RpcBlockInner::Block(block)
@@ -176,23 +176,6 @@ impl<E: EthSpec> RpcBlock<E> {
         })
     }
 
-    pub fn new_from_fixed(
-        block_root: Hash256,
-        block: Arc<SignedBeaconBlock<E>>,
-        blobs: FixedBlobSidecarList<E>,
-    ) -> Result<Self, AvailabilityCheckError> {
-        let filtered = blobs
-            .into_iter()
-            .filter_map(|b| b.clone())
-            .collect::<Vec<_>>();
-        let blobs = if filtered.is_empty() {
-            None
-        } else {
-            Some(VariableList::from(filtered))
-        };
-        Self::new(Some(block_root), block, blobs)
-    }
-
     #[allow(clippy::type_complexity)]
     pub fn deconstruct(
         self,
@@ -355,7 +338,8 @@ impl<E: EthSpec> AvailabilityPendingExecutedBlock<E> {
     }
 }
 
-#[derive(Debug, PartialEq)]
+#[derive(Debug, Derivative)]
+#[derivative(PartialEq)]
 pub struct BlockImportData<E: EthSpec> {
     pub block_root: Hash256,
     pub state: BeaconState<E>,
@@ -363,6 +347,12 @@ pub struct BlockImportData<E: EthSpec> {
     pub parent_eth1_finalization_data: Eth1FinalizationData,
     pub confirmed_state_roots: Vec<Hash256>,
     pub consensus_context: ConsensusContext<E>,
+    #[derivative(PartialEq = "ignore")]
+    /// An optional receiver for `DataColumnSidecarList`.
+    ///
+    /// This field is `Some` when data columns are being computed asynchronously.
+    /// The resulting `DataColumnSidecarList` will be sent through this receiver.
+    pub data_column_recv: Option<oneshot::Receiver<DataColumnSidecarList<E>>>,
 }
 
 impl<E: EthSpec> BlockImportData<E> {
@@ -381,6 +371,7 @@ impl<E: EthSpec> BlockImportData<E> {
             },
             confirmed_state_roots: vec![],
             consensus_context: ConsensusContext::new(Slot::new(0)),
+            data_column_recv: None,
         }
     }
 }
diff --git a/beacon_node/beacon_chain/src/builder.rs b/beacon_node/beacon_chain/src/builder.rs
index d1088b849c..2a201b1aeb 100644
--- a/beacon_node/beacon_chain/src/builder.rs
+++ b/beacon_node/beacon_chain/src/builder.rs
@@ -9,6 +9,7 @@ use crate::fork_choice_signal::ForkChoiceSignalTx;
 use crate::fork_revert::{reset_fork_choice_to_finalization, revert_to_fork_boundary};
 use crate::graffiti_calculator::{GraffitiCalculator, GraffitiOrigin};
 use crate::head_tracker::HeadTracker;
+use crate::kzg_utils::blobs_to_data_column_sidecars;
 use crate::light_client_server_cache::LightClientServerCache;
 use crate::migrate::{BackgroundMigrator, MigratorConfig};
 use crate::observed_data_sidecars::ObservedDataSidecars;
@@ -562,9 +563,30 @@ where
             .put_block(&weak_subj_block_root, weak_subj_block.clone())
             .map_err(|e| format!("Failed to store weak subjectivity block: {e:?}"))?;
         if let Some(blobs) = weak_subj_blobs {
-            store
-                .put_blobs(&weak_subj_block_root, blobs)
-                .map_err(|e| format!("Failed to store weak subjectivity blobs: {e:?}"))?;
+            if self
+                .spec
+                .is_peer_das_enabled_for_epoch(weak_subj_block.epoch())
+            {
+                // After PeerDAS recompute columns from blobs to not force the checkpointz server
+                // into exposing another route.
+                let blobs = blobs
+                    .iter()
+                    .map(|blob_sidecar| &blob_sidecar.blob)
+                    .collect::<Vec<_>>();
+                let data_columns =
+                    blobs_to_data_column_sidecars(&blobs, &weak_subj_block, &self.kzg, &self.spec)
+                        .map_err(|e| {
+                            format!("Failed to compute weak subjectivity data_columns: {e:?}")
+                        })?;
+                // TODO(das): only persist the columns under custody
+                store
+                    .put_data_columns(&weak_subj_block_root, data_columns)
+                    .map_err(|e| format!("Failed to store weak subjectivity data_column: {e:?}"))?;
+            } else {
+                store
+                    .put_blobs(&weak_subj_block_root, blobs)
+                    .map_err(|e| format!("Failed to store weak subjectivity blobs: {e:?}"))?;
+            }
         }
 
         // Stage the database's metadata fields for atomic storage when `build` is called.
diff --git a/beacon_node/beacon_chain/src/canonical_head.rs b/beacon_node/beacon_chain/src/canonical_head.rs
index 9cbeb03246..9c0067e3b4 100644
--- a/beacon_node/beacon_chain/src/canonical_head.rs
+++ b/beacon_node/beacon_chain/src/canonical_head.rs
@@ -1259,11 +1259,7 @@ pub fn find_reorg_slot<E: EthSpec>(
         ($state: ident, $block_root: ident) => {
             std::iter::once(Ok(($state.slot(), $block_root)))
                 .chain($state.rev_iter_block_roots(spec))
-                .skip_while(|result| {
-                    result
-                        .as_ref()
-                        .map_or(false, |(slot, _)| *slot > lowest_slot)
-                })
+                .skip_while(|result| result.as_ref().is_ok_and(|(slot, _)| *slot > lowest_slot))
         };
     }
 
diff --git a/beacon_node/beacon_chain/src/data_availability_checker.rs b/beacon_node/beacon_chain/src/data_availability_checker.rs
index 72806a74d2..aa4689121c 100644
--- a/beacon_node/beacon_chain/src/data_availability_checker.rs
+++ b/beacon_node/beacon_chain/src/data_availability_checker.rs
@@ -15,6 +15,7 @@ use std::num::NonZeroUsize;
 use std::sync::Arc;
 use std::time::Duration;
 use task_executor::TaskExecutor;
+use tokio::sync::oneshot;
 use types::blob_sidecar::{BlobIdentifier, BlobSidecar, FixedBlobSidecarList};
 use types::{
     BlobSidecarList, ChainSpec, DataColumnIdentifier, DataColumnSidecar, DataColumnSidecarList,
@@ -116,21 +117,16 @@ impl<T: BeaconChainTypes> DataAvailabilityChecker<T> {
         spec: Arc<ChainSpec>,
         log: Logger,
     ) -> Result<Self, AvailabilityCheckError> {
-        let custody_subnet_count = if import_all_data_columns {
-            spec.data_column_sidecar_subnet_count as usize
-        } else {
-            spec.custody_requirement as usize
-        };
-
-        let subnet_sampling_size =
-            std::cmp::max(custody_subnet_count, spec.samples_per_slot as usize);
-        let sampling_column_count =
-            subnet_sampling_size.saturating_mul(spec.data_columns_per_subnet());
+        let custody_group_count = spec.custody_group_count(import_all_data_columns);
+        // This should only panic if the chain spec contains invalid values.
+        let sampling_size = spec
+            .sampling_size(custody_group_count)
+            .expect("should compute node sampling size from valid chain spec");
 
         let inner = DataAvailabilityCheckerInner::new(
             OVERFLOW_LRU_CAPACITY,
             store,
-            sampling_column_count,
+            sampling_size as usize,
             spec.clone(),
         )?;
         Ok(Self {
@@ -147,7 +143,7 @@ impl<T: BeaconChainTypes> DataAvailabilityChecker<T> {
     }
 
     pub(crate) fn is_supernode(&self) -> bool {
-        self.get_sampling_column_count() == self.spec.number_of_columns
+        self.get_sampling_column_count() == self.spec.number_of_columns as usize
     }
 
     /// Checks if the block root is currenlty in the availability cache awaiting import because
@@ -215,12 +211,15 @@ impl<T: BeaconChainTypes> DataAvailabilityChecker<T> {
         // Note: currently not reporting which specific blob is invalid because we fetch all blobs
         // from the same peer for both lookup and range sync.
 
-        let verified_blobs =
-            KzgVerifiedBlobList::new(blobs.iter().flatten().cloned(), &self.kzg, seen_timestamp)
-                .map_err(AvailabilityCheckError::InvalidBlobs)?;
+        let verified_blobs = KzgVerifiedBlobList::new(
+            blobs.into_vec().into_iter().flatten(),
+            &self.kzg,
+            seen_timestamp,
+        )
+        .map_err(AvailabilityCheckError::InvalidBlobs)?;
 
         self.availability_cache
-            .put_kzg_verified_blobs(block_root, verified_blobs, &self.log)
+            .put_kzg_verified_blobs(block_root, verified_blobs, None, &self.log)
     }
 
     /// Put a list of custody columns received via RPC into the availability cache. This performs KZG
@@ -260,6 +259,7 @@ impl<T: BeaconChainTypes> DataAvailabilityChecker<T> {
         &self,
         block_root: Hash256,
         blobs: FixedBlobSidecarList<T::EthSpec>,
+        data_column_recv: Option<oneshot::Receiver<DataColumnSidecarList<T::EthSpec>>>,
     ) -> Result<Availability<T::EthSpec>, AvailabilityCheckError> {
         let seen_timestamp = self
             .slot_clock
@@ -269,8 +269,12 @@ impl<T: BeaconChainTypes> DataAvailabilityChecker<T> {
         let verified_blobs =
             KzgVerifiedBlobList::from_verified(blobs.iter().flatten().cloned(), seen_timestamp);
 
-        self.availability_cache
-            .put_kzg_verified_blobs(block_root, verified_blobs, &self.log)
+        self.availability_cache.put_kzg_verified_blobs(
+            block_root,
+            verified_blobs,
+            data_column_recv,
+            &self.log,
+        )
     }
 
     /// Check if we've cached other blobs for this block. If it completes a set and we also
@@ -285,6 +289,7 @@ impl<T: BeaconChainTypes> DataAvailabilityChecker<T> {
         self.availability_cache.put_kzg_verified_blobs(
             gossip_blob.block_root(),
             vec![gossip_blob.into_inner()],
+            None,
             &self.log,
         )
     }
@@ -400,14 +405,13 @@ impl<T: BeaconChainTypes> DataAvailabilityChecker<T> {
         blocks: Vec<RpcBlock<T::EthSpec>>,
     ) -> Result<Vec<MaybeAvailableBlock<T::EthSpec>>, AvailabilityCheckError> {
         let mut results = Vec::with_capacity(blocks.len());
-        let all_blobs: BlobSidecarList<T::EthSpec> = blocks
+        let all_blobs = blocks
             .iter()
             .filter(|block| self.blobs_required_for_block(block.as_block()))
             // this clone is cheap as it's cloning an Arc
             .filter_map(|block| block.blobs().cloned())
             .flatten()
-            .collect::<Vec<_>>()
-            .into();
+            .collect::<Vec<_>>();
 
         // verify kzg for all blobs at once
         if !all_blobs.is_empty() {
@@ -424,7 +428,7 @@ impl<T: BeaconChainTypes> DataAvailabilityChecker<T> {
             .map(CustodyDataColumn::into_inner)
             .collect::<Vec<_>>();
         let all_data_columns =
-            RuntimeVariableList::from_vec(all_data_columns, self.spec.number_of_columns);
+            RuntimeVariableList::from_vec(all_data_columns, self.spec.number_of_columns as usize);
 
         // verify kzg for all data columns at once
         if !all_data_columns.is_empty() {
@@ -519,13 +523,13 @@ impl<T: BeaconChainTypes> DataAvailabilityChecker<T> {
     /// Returns true if the given epoch lies within the da boundary and false otherwise.
     pub fn da_check_required_for_epoch(&self, block_epoch: Epoch) -> bool {
         self.data_availability_boundary()
-            .map_or(false, |da_epoch| block_epoch >= da_epoch)
+            .is_some_and(|da_epoch| block_epoch >= da_epoch)
     }
 
     /// Returns `true` if the current epoch is greater than or equal to the `Deneb` epoch.
     pub fn is_deneb(&self) -> bool {
-        self.slot_clock.now().map_or(false, |slot| {
-            self.spec.deneb_fork_epoch.map_or(false, |deneb_epoch| {
+        self.slot_clock.now().is_some_and(|slot| {
+            self.spec.deneb_fork_epoch.is_some_and(|deneb_epoch| {
                 let now_epoch = slot.epoch(T::EthSpec::slots_per_epoch());
                 now_epoch >= deneb_epoch
             })
@@ -801,7 +805,6 @@ impl<E: EthSpec> AvailableBlock<E> {
             block,
             blobs,
             data_columns,
-            blobs_available_timestamp: _,
             ..
         } = self;
         (block_root, block, blobs, data_columns)
diff --git a/beacon_node/beacon_chain/src/data_availability_checker/overflow_lru_cache.rs b/beacon_node/beacon_chain/src/data_availability_checker/overflow_lru_cache.rs
index 40361574af..cd793c8394 100644
--- a/beacon_node/beacon_chain/src/data_availability_checker/overflow_lru_cache.rs
+++ b/beacon_node/beacon_chain/src/data_availability_checker/overflow_lru_cache.rs
@@ -10,40 +10,55 @@ use crate::BeaconChainTypes;
 use lru::LruCache;
 use parking_lot::RwLock;
 use slog::{debug, Logger};
-use ssz_types::FixedVector;
 use std::num::NonZeroUsize;
 use std::sync::Arc;
+use tokio::sync::oneshot;
 use types::blob_sidecar::BlobIdentifier;
 use types::{
-    BlobSidecar, ChainSpec, ColumnIndex, DataColumnIdentifier, DataColumnSidecar, Epoch, EthSpec,
-    Hash256, SignedBeaconBlock,
+    BlobSidecar, ChainSpec, ColumnIndex, DataColumnIdentifier, DataColumnSidecar,
+    DataColumnSidecarList, Epoch, EthSpec, Hash256, RuntimeFixedVector, RuntimeVariableList,
+    SignedBeaconBlock,
 };
 
 /// This represents the components of a partially available block
 ///
 /// The blobs are all gossip and kzg verified.
 /// The block has completed all verifications except the availability check.
-/// TODO(das): this struct can potentially be reafactored as blobs and data columns are mutually
-/// exclusive and this could simplify `is_importable`.
-#[derive(Clone)]
 pub struct PendingComponents<E: EthSpec> {
     pub block_root: Hash256,
-    pub verified_blobs: FixedVector<Option<KzgVerifiedBlob<E>>, E::MaxBlobsPerBlock>,
+    pub verified_blobs: RuntimeFixedVector<Option<KzgVerifiedBlob<E>>>,
     pub verified_data_columns: Vec<KzgVerifiedCustodyDataColumn<E>>,
     pub executed_block: Option<DietAvailabilityPendingExecutedBlock<E>>,
     pub reconstruction_started: bool,
+    /// Receiver for data columns that are computed asynchronously;
+    ///
+    /// If `data_column_recv` is `Some`, it means data column computation or reconstruction has been
+    /// started. This can happen either via engine blobs fetching or data column reconstruction
+    /// (triggered when >= 50% columns are received via gossip).
+    pub data_column_recv: Option<oneshot::Receiver<DataColumnSidecarList<E>>>,
 }
 
 impl<E: EthSpec> PendingComponents<E> {
+    /// Clones the `PendingComponent` without cloning `data_column_recv`, as `Receiver` is not cloneable.
+    /// This should only be used when the receiver is no longer needed.
+    pub fn clone_without_column_recv(&self) -> Self {
+        PendingComponents {
+            block_root: self.block_root,
+            verified_blobs: self.verified_blobs.clone(),
+            verified_data_columns: self.verified_data_columns.clone(),
+            executed_block: self.executed_block.clone(),
+            reconstruction_started: self.reconstruction_started,
+            data_column_recv: None,
+        }
+    }
+
     /// Returns an immutable reference to the cached block.
     pub fn get_cached_block(&self) -> &Option<DietAvailabilityPendingExecutedBlock<E>> {
         &self.executed_block
     }
 
     /// Returns an immutable reference to the fixed vector of cached blobs.
-    pub fn get_cached_blobs(
-        &self,
-    ) -> &FixedVector<Option<KzgVerifiedBlob<E>>, E::MaxBlobsPerBlock> {
+    pub fn get_cached_blobs(&self) -> &RuntimeFixedVector<Option<KzgVerifiedBlob<E>>> {
         &self.verified_blobs
     }
 
@@ -64,9 +79,7 @@ impl<E: EthSpec> PendingComponents<E> {
     }
 
     /// Returns a mutable reference to the fixed vector of cached blobs.
-    pub fn get_cached_blobs_mut(
-        &mut self,
-    ) -> &mut FixedVector<Option<KzgVerifiedBlob<E>>, E::MaxBlobsPerBlock> {
+    pub fn get_cached_blobs_mut(&mut self) -> &mut RuntimeFixedVector<Option<KzgVerifiedBlob<E>>> {
         &mut self.verified_blobs
     }
 
@@ -138,10 +151,7 @@ impl<E: EthSpec> PendingComponents<E> {
     /// Blobs are only inserted if:
     /// 1. The blob entry at the index is empty and no block exists.
     /// 2. The block exists and its commitment matches the blob's commitment.
-    pub fn merge_blobs(
-        &mut self,
-        blobs: FixedVector<Option<KzgVerifiedBlob<E>>, E::MaxBlobsPerBlock>,
-    ) {
+    pub fn merge_blobs(&mut self, blobs: RuntimeFixedVector<Option<KzgVerifiedBlob<E>>>) {
         for (index, blob) in blobs.iter().cloned().enumerate() {
             let Some(blob) = blob else { continue };
             self.merge_single_blob(index, blob);
@@ -185,7 +195,7 @@ impl<E: EthSpec> PendingComponents<E> {
     /// Blobs that don't match the new block's commitments are evicted.
     pub fn merge_block(&mut self, block: DietAvailabilityPendingExecutedBlock<E>) {
         self.insert_block(block);
-        let reinsert = std::mem::take(self.get_cached_blobs_mut());
+        let reinsert = self.get_cached_blobs_mut().take();
         self.merge_blobs(reinsert);
     }
 
@@ -228,25 +238,23 @@ impl<E: EthSpec> PendingComponents<E> {
         );
 
         let all_blobs_received = block_kzg_commitments_count_opt
-            .map_or(false, |num_expected_blobs| {
-                num_expected_blobs == num_received_blobs
-            });
+            .is_some_and(|num_expected_blobs| num_expected_blobs == num_received_blobs);
 
-        let all_columns_received = expected_columns_opt.map_or(false, |num_expected_columns| {
-            num_expected_columns == num_received_columns
-        });
+        let all_columns_received = expected_columns_opt
+            .is_some_and(|num_expected_columns| num_expected_columns == num_received_columns);
 
         all_blobs_received || all_columns_received
     }
 
     /// Returns an empty `PendingComponents` object with the given block root.
-    pub fn empty(block_root: Hash256) -> Self {
+    pub fn empty(block_root: Hash256, max_len: usize) -> Self {
         Self {
             block_root,
-            verified_blobs: FixedVector::default(),
+            verified_blobs: RuntimeFixedVector::new(vec![None; max_len]),
             verified_data_columns: vec![],
             executed_block: None,
             reconstruction_started: false,
+            data_column_recv: None,
         }
     }
 
@@ -271,6 +279,7 @@ impl<E: EthSpec> PendingComponents<E> {
             verified_blobs,
             verified_data_columns,
             executed_block,
+            data_column_recv,
             ..
         } = self;
 
@@ -302,17 +311,22 @@ impl<E: EthSpec> PendingComponents<E> {
             else {
                 return Err(AvailabilityCheckError::Unexpected);
             };
-            (Some(verified_blobs), None)
+            let max_len = spec.max_blobs_per_block(diet_executed_block.as_block().epoch()) as usize;
+            (
+                Some(RuntimeVariableList::new(verified_blobs, max_len)?),
+                None,
+            )
         };
-
         let executed_block = recover(diet_executed_block)?;
 
         let AvailabilityPendingExecutedBlock {
             block,
-            import_data,
+            mut import_data,
             payload_verification_outcome,
         } = executed_block;
 
+        import_data.data_column_recv = data_column_recv;
+
         let available_block = AvailableBlock {
             block_root,
             block,
@@ -344,10 +358,7 @@ impl<E: EthSpec> PendingComponents<E> {
                 }
 
                 if let Some(kzg_verified_data_column) = self.verified_data_columns.first() {
-                    let epoch = kzg_verified_data_column
-                        .as_data_column()
-                        .slot()
-                        .epoch(E::slots_per_epoch());
+                    let epoch = kzg_verified_data_column.as_data_column().epoch();
                     return Some(epoch);
                 }
 
@@ -454,13 +465,31 @@ impl<T: BeaconChainTypes> DataAvailabilityCheckerInner<T> {
         f(self.critical.read().peek(block_root))
     }
 
+    /// Puts the KZG verified blobs into the availability cache as pending components.
+    ///
+    /// The `data_column_recv` parameter is an optional `Receiver` for data columns that are
+    /// computed asynchronously. This method remains **used** after PeerDAS activation, because
+    /// blocks can be made available if the EL already has the blobs and returns them via the
+    /// `getBlobsV1` engine method. More details in [fetch_blobs.rs](https://github.com/sigp/lighthouse/blob/44f8add41ea2252769bb967864af95b3c13af8ca/beacon_node/beacon_chain/src/fetch_blobs.rs).
     pub fn put_kzg_verified_blobs<I: IntoIterator<Item = KzgVerifiedBlob<T::EthSpec>>>(
         &self,
         block_root: Hash256,
         kzg_verified_blobs: I,
+        data_column_recv: Option<oneshot::Receiver<DataColumnSidecarList<T::EthSpec>>>,
         log: &Logger,
     ) -> Result<Availability<T::EthSpec>, AvailabilityCheckError> {
-        let mut fixed_blobs = FixedVector::default();
+        let mut kzg_verified_blobs = kzg_verified_blobs.into_iter().peekable();
+
+        let Some(epoch) = kzg_verified_blobs
+            .peek()
+            .map(|verified_blob| verified_blob.as_blob().epoch())
+        else {
+            // Verified blobs list should be non-empty.
+            return Err(AvailabilityCheckError::Unexpected);
+        };
+
+        let mut fixed_blobs =
+            RuntimeFixedVector::new(vec![None; self.spec.max_blobs_per_block(epoch) as usize]);
 
         for blob in kzg_verified_blobs {
             if let Some(blob_opt) = fixed_blobs.get_mut(blob.blob_index() as usize) {
@@ -474,14 +503,24 @@ impl<T: BeaconChainTypes> DataAvailabilityCheckerInner<T> {
         let mut pending_components = write_lock
             .pop_entry(&block_root)
             .map(|(_, v)| v)
-            .unwrap_or_else(|| PendingComponents::empty(block_root));
+            .unwrap_or_else(|| {
+                PendingComponents::empty(block_root, self.spec.max_blobs_per_block(epoch) as usize)
+            });
 
         // Merge in the blobs.
         pending_components.merge_blobs(fixed_blobs);
 
+        if data_column_recv.is_some() {
+            // If `data_column_recv` is `Some`, it means we have all the blobs from engine, and have
+            // started computing data columns. We store the receiver in `PendingComponents` for
+            // later use when importing the block.
+            pending_components.data_column_recv = data_column_recv;
+        }
+
         if pending_components.is_available(self.sampling_column_count, log) {
-            write_lock.put(block_root, pending_components.clone());
-            // No need to hold the write lock anymore
+            // We keep the pending components in the availability cache during block import (#5845).
+            // `data_column_recv` is returned as part of the available block and is no longer needed here.
+            write_lock.put(block_root, pending_components.clone_without_column_recv());
             drop(write_lock);
             pending_components.make_available(&self.spec, |diet_block| {
                 self.state_cache.recover_pending_executed_block(diet_block)
@@ -501,20 +540,32 @@ impl<T: BeaconChainTypes> DataAvailabilityCheckerInner<T> {
         kzg_verified_data_columns: I,
         log: &Logger,
     ) -> Result<Availability<T::EthSpec>, AvailabilityCheckError> {
+        let mut kzg_verified_data_columns = kzg_verified_data_columns.into_iter().peekable();
+        let Some(epoch) = kzg_verified_data_columns
+            .peek()
+            .map(|verified_blob| verified_blob.as_data_column().epoch())
+        else {
+            // Verified data_columns list should be non-empty.
+            return Err(AvailabilityCheckError::Unexpected);
+        };
+
         let mut write_lock = self.critical.write();
 
         // Grab existing entry or create a new entry.
         let mut pending_components = write_lock
             .pop_entry(&block_root)
             .map(|(_, v)| v)
-            .unwrap_or_else(|| PendingComponents::empty(block_root));
+            .unwrap_or_else(|| {
+                PendingComponents::empty(block_root, self.spec.max_blobs_per_block(epoch) as usize)
+            });
 
         // Merge in the data columns.
         pending_components.merge_data_columns(kzg_verified_data_columns)?;
 
         if pending_components.is_available(self.sampling_column_count, log) {
-            write_lock.put(block_root, pending_components.clone());
-            // No need to hold the write lock anymore
+            // We keep the pending components in the availability cache during block import (#5845).
+            // `data_column_recv` is returned as part of the available block and is no longer needed here.
+            write_lock.put(block_root, pending_components.clone_without_column_recv());
             drop(write_lock);
             pending_components.make_available(&self.spec, |diet_block| {
                 self.state_cache.recover_pending_executed_block(diet_block)
@@ -546,7 +597,7 @@ impl<T: BeaconChainTypes> DataAvailabilityCheckerInner<T> {
 
         // If we're sampling all columns, it means we must be custodying all columns.
         let custody_column_count = self.sampling_column_count();
-        let total_column_count = self.spec.number_of_columns;
+        let total_column_count = self.spec.number_of_columns as usize;
         let received_column_count = pending_components.verified_data_columns.len();
 
         if pending_components.reconstruction_started {
@@ -555,7 +606,7 @@ impl<T: BeaconChainTypes> DataAvailabilityCheckerInner<T> {
         if custody_column_count != total_column_count {
             return ReconstructColumnsDecision::No("not required for full node");
         }
-        if received_column_count == self.spec.number_of_columns {
+        if received_column_count >= total_column_count {
             return ReconstructColumnsDecision::No("all columns received");
         }
         if received_column_count < total_column_count / 2 {
@@ -563,7 +614,7 @@ impl<T: BeaconChainTypes> DataAvailabilityCheckerInner<T> {
         }
 
         pending_components.reconstruction_started = true;
-        ReconstructColumnsDecision::Yes(pending_components.clone())
+        ReconstructColumnsDecision::Yes(pending_components.clone_without_column_recv())
     }
 
     /// This could mean some invalid data columns made it through to the `DataAvailabilityChecker`.
@@ -584,6 +635,7 @@ impl<T: BeaconChainTypes> DataAvailabilityCheckerInner<T> {
         log: &Logger,
     ) -> Result<Availability<T::EthSpec>, AvailabilityCheckError> {
         let mut write_lock = self.critical.write();
+        let epoch = executed_block.as_block().epoch();
         let block_root = executed_block.import_data.block_root;
 
         // register the block to get the diet block
@@ -595,15 +647,18 @@ impl<T: BeaconChainTypes> DataAvailabilityCheckerInner<T> {
         let mut pending_components = write_lock
             .pop_entry(&block_root)
             .map(|(_, v)| v)
-            .unwrap_or_else(|| PendingComponents::empty(block_root));
+            .unwrap_or_else(|| {
+                PendingComponents::empty(block_root, self.spec.max_blobs_per_block(epoch) as usize)
+            });
 
         // Merge in the block.
         pending_components.merge_block(diet_executed_block);
 
         // Check if we have all components and entire set is consistent.
         if pending_components.is_available(self.sampling_column_count, log) {
-            write_lock.put(block_root, pending_components.clone());
-            // No need to hold the write lock anymore
+            // We keep the pending components in the availability cache during block import (#5845).
+            // `data_column_recv` is returned as part of the available block and is no longer needed here.
+            write_lock.put(block_root, pending_components.clone_without_column_recv());
             drop(write_lock);
             pending_components.make_available(&self.spec, |diet_block| {
                 self.state_cache.recover_pending_executed_block(diet_block)
@@ -676,7 +731,7 @@ mod test {
     use slog::{info, Logger};
     use state_processing::ConsensusContext;
     use std::collections::VecDeque;
-    use store::{HotColdDB, ItemStore, LevelDB, StoreConfig};
+    use store::{database::interface::BeaconNodeBackend, HotColdDB, ItemStore, StoreConfig};
     use tempfile::{tempdir, TempDir};
     use types::non_zero_usize::new_non_zero_usize;
     use types::{ExecPayload, MinimalEthSpec};
@@ -688,7 +743,7 @@ mod test {
         db_path: &TempDir,
         spec: Arc<ChainSpec>,
         log: Logger,
-    ) -> Arc<HotColdDB<E, LevelDB<E>, LevelDB<E>>> {
+    ) -> Arc<HotColdDB<E, BeaconNodeBackend<E>, BeaconNodeBackend<E>>> {
         let hot_path = db_path.path().join("hot_db");
         let cold_path = db_path.path().join("cold_db");
         let blobs_path = db_path.path().join("blobs_db");
@@ -815,7 +870,8 @@ mod test {
         info!(log, "done printing kzg commitments");
 
         let gossip_verified_blobs = if let Some((kzg_proofs, blobs)) = maybe_blobs {
-            let sidecars = BlobSidecar::build_sidecars(blobs, &block, kzg_proofs).unwrap();
+            let sidecars =
+                BlobSidecar::build_sidecars(blobs, &block, kzg_proofs, &chain.spec).unwrap();
             Vec::from(sidecars)
                 .into_iter()
                 .map(|sidecar| {
@@ -837,6 +893,7 @@ mod test {
             parent_eth1_finalization_data,
             confirmed_state_roots: vec![],
             consensus_context,
+            data_column_recv: None,
         };
 
         let payload_verification_outcome = PayloadVerificationOutcome {
@@ -862,7 +919,11 @@ mod test {
     )
     where
         E: EthSpec,
-        T: BeaconChainTypes<HotStore = LevelDB<E>, ColdStore = LevelDB<E>, EthSpec = E>,
+        T: BeaconChainTypes<
+            HotStore = BeaconNodeBackend<E>,
+            ColdStore = BeaconNodeBackend<E>,
+            EthSpec = E,
+        >,
     {
         let log = test_logger();
         let chain_db_path = tempdir().expect("should get temp dir");
@@ -939,7 +1000,7 @@ mod test {
         for (blob_index, gossip_blob) in blobs.into_iter().enumerate() {
             kzg_verified_blobs.push(gossip_blob.into_inner());
             let availability = cache
-                .put_kzg_verified_blobs(root, kzg_verified_blobs.clone(), harness.logger())
+                .put_kzg_verified_blobs(root, kzg_verified_blobs.clone(), None, harness.logger())
                 .expect("should put blob");
             if blob_index == blobs_expected - 1 {
                 assert!(matches!(availability, Availability::Available(_)));
@@ -948,6 +1009,8 @@ mod test {
                 assert_eq!(cache.critical.read().len(), 1);
             }
         }
+        // remove the blob to simulate successful import
+        cache.remove_pending_components(root);
         assert!(
             cache.critical.read().is_empty(),
             "cache should be empty now that all components available"
@@ -965,7 +1028,7 @@ mod test {
         for gossip_blob in blobs {
             kzg_verified_blobs.push(gossip_blob.into_inner());
             let availability = cache
-                .put_kzg_verified_blobs(root, kzg_verified_blobs.clone(), harness.logger())
+                .put_kzg_verified_blobs(root, kzg_verified_blobs.clone(), None, harness.logger())
                 .expect("should put blob");
             assert_eq!(
                 availability,
@@ -1128,7 +1191,7 @@ mod pending_components_tests {
     use super::*;
     use crate::block_verification_types::BlockImportData;
     use crate::eth1_finalization_cache::Eth1FinalizationData;
-    use crate::test_utils::{generate_rand_block_and_blobs, NumBlobs};
+    use crate::test_utils::{generate_rand_block_and_blobs, test_spec, NumBlobs};
     use crate::PayloadVerificationOutcome;
     use fork_choice::PayloadVerificationStatus;
     use kzg::KzgCommitment;
@@ -1144,15 +1207,19 @@ mod pending_components_tests {
 
     type Setup<E> = (
         SignedBeaconBlock<E>,
-        FixedVector<Option<Arc<BlobSidecar<E>>>, <E as EthSpec>::MaxBlobsPerBlock>,
-        FixedVector<Option<Arc<BlobSidecar<E>>>, <E as EthSpec>::MaxBlobsPerBlock>,
+        RuntimeFixedVector<Option<Arc<BlobSidecar<E>>>>,
+        RuntimeFixedVector<Option<Arc<BlobSidecar<E>>>>,
+        usize,
     );
 
     pub fn pre_setup() -> Setup<E> {
         let mut rng = StdRng::seed_from_u64(0xDEADBEEF0BAD5EEDu64);
+        let spec = test_spec::<E>();
         let (block, blobs_vec) =
-            generate_rand_block_and_blobs::<E>(ForkName::Deneb, NumBlobs::Random, &mut rng);
-        let mut blobs: FixedVector<_, <E as EthSpec>::MaxBlobsPerBlock> = FixedVector::default();
+            generate_rand_block_and_blobs::<E>(ForkName::Deneb, NumBlobs::Random, &mut rng, &spec);
+        let max_len = spec.max_blobs_per_block(block.epoch()) as usize;
+        let mut blobs: RuntimeFixedVector<Option<Arc<BlobSidecar<E>>>> =
+            RuntimeFixedVector::default(max_len);
 
         for blob in blobs_vec {
             if let Some(b) = blobs.get_mut(blob.index as usize) {
@@ -1160,10 +1227,8 @@ mod pending_components_tests {
             }
         }
 
-        let mut invalid_blobs: FixedVector<
-            Option<Arc<BlobSidecar<E>>>,
-            <E as EthSpec>::MaxBlobsPerBlock,
-        > = FixedVector::default();
+        let mut invalid_blobs: RuntimeFixedVector<Option<Arc<BlobSidecar<E>>>> =
+            RuntimeFixedVector::default(max_len);
         for (index, blob) in blobs.iter().enumerate() {
             if let Some(invalid_blob) = blob {
                 let mut blob_copy = invalid_blob.as_ref().clone();
@@ -1172,21 +1237,21 @@ mod pending_components_tests {
             }
         }
 
-        (block, blobs, invalid_blobs)
+        (block, blobs, invalid_blobs, max_len)
     }
 
     type PendingComponentsSetup<E> = (
         DietAvailabilityPendingExecutedBlock<E>,
-        FixedVector<Option<KzgVerifiedBlob<E>>, <E as EthSpec>::MaxBlobsPerBlock>,
-        FixedVector<Option<KzgVerifiedBlob<E>>, <E as EthSpec>::MaxBlobsPerBlock>,
+        RuntimeFixedVector<Option<KzgVerifiedBlob<E>>>,
+        RuntimeFixedVector<Option<KzgVerifiedBlob<E>>>,
     );
 
     pub fn setup_pending_components(
         block: SignedBeaconBlock<E>,
-        valid_blobs: FixedVector<Option<Arc<BlobSidecar<E>>>, <E as EthSpec>::MaxBlobsPerBlock>,
-        invalid_blobs: FixedVector<Option<Arc<BlobSidecar<E>>>, <E as EthSpec>::MaxBlobsPerBlock>,
+        valid_blobs: RuntimeFixedVector<Option<Arc<BlobSidecar<E>>>>,
+        invalid_blobs: RuntimeFixedVector<Option<Arc<BlobSidecar<E>>>>,
     ) -> PendingComponentsSetup<E> {
-        let blobs = FixedVector::from(
+        let blobs = RuntimeFixedVector::new(
             valid_blobs
                 .iter()
                 .map(|blob_opt| {
@@ -1196,7 +1261,7 @@ mod pending_components_tests {
                 })
                 .collect::<Vec<_>>(),
         );
-        let invalid_blobs = FixedVector::from(
+        let invalid_blobs = RuntimeFixedVector::new(
             invalid_blobs
                 .iter()
                 .map(|blob_opt| {
@@ -1219,6 +1284,7 @@ mod pending_components_tests {
                 },
                 confirmed_state_roots: vec![],
                 consensus_context: ConsensusContext::new(Slot::new(0)),
+                data_column_recv: None,
             },
             payload_verification_outcome: PayloadVerificationOutcome {
                 payload_verification_status: PayloadVerificationStatus::Verified,
@@ -1228,10 +1294,10 @@ mod pending_components_tests {
         (block.into(), blobs, invalid_blobs)
     }
 
-    pub fn assert_cache_consistent(cache: PendingComponents<E>) {
+    pub fn assert_cache_consistent(cache: PendingComponents<E>, max_len: usize) {
         if let Some(cached_block) = cache.get_cached_block() {
             let cached_block_commitments = cached_block.get_commitments();
-            for index in 0..E::max_blobs_per_block() {
+            for index in 0..max_len {
                 let block_commitment = cached_block_commitments.get(index).copied();
                 let blob_commitment_opt = cache.get_cached_blobs().get(index).unwrap();
                 let blob_commitment = blob_commitment_opt.as_ref().map(|b| *b.get_commitment());
@@ -1250,40 +1316,40 @@ mod pending_components_tests {
 
     #[test]
     fn valid_block_invalid_blobs_valid_blobs() {
-        let (block_commitments, blobs, random_blobs) = pre_setup();
+        let (block_commitments, blobs, random_blobs, max_len) = pre_setup();
         let (block_commitments, blobs, random_blobs) =
             setup_pending_components(block_commitments, blobs, random_blobs);
         let block_root = Hash256::zero();
-        let mut cache = <PendingComponents<E>>::empty(block_root);
+        let mut cache = <PendingComponents<E>>::empty(block_root, max_len);
         cache.merge_block(block_commitments);
         cache.merge_blobs(random_blobs);
         cache.merge_blobs(blobs);
 
-        assert_cache_consistent(cache);
+        assert_cache_consistent(cache, max_len);
     }
 
     #[test]
     fn invalid_blobs_block_valid_blobs() {
-        let (block_commitments, blobs, random_blobs) = pre_setup();
+        let (block_commitments, blobs, random_blobs, max_len) = pre_setup();
         let (block_commitments, blobs, random_blobs) =
             setup_pending_components(block_commitments, blobs, random_blobs);
         let block_root = Hash256::zero();
-        let mut cache = <PendingComponents<E>>::empty(block_root);
+        let mut cache = <PendingComponents<E>>::empty(block_root, max_len);
         cache.merge_blobs(random_blobs);
         cache.merge_block(block_commitments);
         cache.merge_blobs(blobs);
 
-        assert_cache_consistent(cache);
+        assert_cache_consistent(cache, max_len);
     }
 
     #[test]
     fn invalid_blobs_valid_blobs_block() {
-        let (block_commitments, blobs, random_blobs) = pre_setup();
+        let (block_commitments, blobs, random_blobs, max_len) = pre_setup();
         let (block_commitments, blobs, random_blobs) =
             setup_pending_components(block_commitments, blobs, random_blobs);
 
         let block_root = Hash256::zero();
-        let mut cache = <PendingComponents<E>>::empty(block_root);
+        let mut cache = <PendingComponents<E>>::empty(block_root, max_len);
         cache.merge_blobs(random_blobs);
         cache.merge_blobs(blobs);
         cache.merge_block(block_commitments);
@@ -1293,46 +1359,46 @@ mod pending_components_tests {
 
     #[test]
     fn block_valid_blobs_invalid_blobs() {
-        let (block_commitments, blobs, random_blobs) = pre_setup();
+        let (block_commitments, blobs, random_blobs, max_len) = pre_setup();
         let (block_commitments, blobs, random_blobs) =
             setup_pending_components(block_commitments, blobs, random_blobs);
 
         let block_root = Hash256::zero();
-        let mut cache = <PendingComponents<E>>::empty(block_root);
+        let mut cache = <PendingComponents<E>>::empty(block_root, max_len);
         cache.merge_block(block_commitments);
         cache.merge_blobs(blobs);
         cache.merge_blobs(random_blobs);
 
-        assert_cache_consistent(cache);
+        assert_cache_consistent(cache, max_len);
     }
 
     #[test]
     fn valid_blobs_block_invalid_blobs() {
-        let (block_commitments, blobs, random_blobs) = pre_setup();
+        let (block_commitments, blobs, random_blobs, max_len) = pre_setup();
         let (block_commitments, blobs, random_blobs) =
             setup_pending_components(block_commitments, blobs, random_blobs);
 
         let block_root = Hash256::zero();
-        let mut cache = <PendingComponents<E>>::empty(block_root);
+        let mut cache = <PendingComponents<E>>::empty(block_root, max_len);
         cache.merge_blobs(blobs);
         cache.merge_block(block_commitments);
         cache.merge_blobs(random_blobs);
 
-        assert_cache_consistent(cache);
+        assert_cache_consistent(cache, max_len);
     }
 
     #[test]
     fn valid_blobs_invalid_blobs_block() {
-        let (block_commitments, blobs, random_blobs) = pre_setup();
+        let (block_commitments, blobs, random_blobs, max_len) = pre_setup();
         let (block_commitments, blobs, random_blobs) =
             setup_pending_components(block_commitments, blobs, random_blobs);
 
         let block_root = Hash256::zero();
-        let mut cache = <PendingComponents<E>>::empty(block_root);
+        let mut cache = <PendingComponents<E>>::empty(block_root, max_len);
         cache.merge_blobs(blobs);
         cache.merge_blobs(random_blobs);
         cache.merge_block(block_commitments);
 
-        assert_cache_consistent(cache);
+        assert_cache_consistent(cache, max_len);
     }
 }
diff --git a/beacon_node/beacon_chain/src/data_availability_checker/state_lru_cache.rs b/beacon_node/beacon_chain/src/data_availability_checker/state_lru_cache.rs
index 5b9b7c7023..2a2a0431cc 100644
--- a/beacon_node/beacon_chain/src/data_availability_checker/state_lru_cache.rs
+++ b/beacon_node/beacon_chain/src/data_availability_checker/state_lru_cache.rs
@@ -136,6 +136,7 @@ impl<T: BeaconChainTypes> StateLRUCache<T> {
                 consensus_context: diet_executed_block
                     .consensus_context
                     .into_consensus_context(),
+                data_column_recv: None,
             },
             payload_verification_outcome: diet_executed_block.payload_verification_outcome,
         })
diff --git a/beacon_node/beacon_chain/src/data_column_verification.rs b/beacon_node/beacon_chain/src/data_column_verification.rs
index 6cfd26786a..565e76704e 100644
--- a/beacon_node/beacon_chain/src/data_column_verification.rs
+++ b/beacon_node/beacon_chain/src/data_column_verification.rs
@@ -423,7 +423,7 @@ fn verify_data_column_sidecar<E: EthSpec>(
     data_column: &DataColumnSidecar<E>,
     spec: &ChainSpec,
 ) -> Result<(), GossipDataColumnError> {
-    if data_column.index >= spec.number_of_columns as u64 {
+    if data_column.index >= spec.number_of_columns {
         return Err(GossipDataColumnError::InvalidColumnIndex(data_column.index));
     }
     if data_column.kzg_commitments.is_empty() {
@@ -611,7 +611,7 @@ fn verify_index_matches_subnet<E: EthSpec>(
     spec: &ChainSpec,
 ) -> Result<(), GossipDataColumnError> {
     let expected_subnet: u64 =
-        DataColumnSubnetId::from_column_index::<E>(data_column.index as usize, spec).into();
+        DataColumnSubnetId::from_column_index(data_column.index, spec).into();
     if expected_subnet != subnet {
         return Err(GossipDataColumnError::InvalidSubnetId {
             received: subnet,
@@ -699,7 +699,7 @@ mod test {
 
     #[tokio::test]
     async fn empty_data_column_sidecars_fails_validation() {
-        let spec = ForkName::latest().make_genesis_spec(E::default_spec());
+        let spec = ForkName::Fulu.make_genesis_spec(E::default_spec());
         let harness = BeaconChainHarness::builder(E::default())
             .spec(spec.into())
             .deterministic_keypairs(64)
diff --git a/beacon_node/beacon_chain/src/early_attester_cache.rs b/beacon_node/beacon_chain/src/early_attester_cache.rs
index 606610a748..c94ea0e941 100644
--- a/beacon_node/beacon_chain/src/early_attester_cache.rs
+++ b/beacon_node/beacon_chain/src/early_attester_cache.rs
@@ -145,7 +145,7 @@ impl<E: EthSpec> EarlyAttesterCache<E> {
         self.item
             .read()
             .as_ref()
-            .map_or(false, |item| item.beacon_block_root == block_root)
+            .is_some_and(|item| item.beacon_block_root == block_root)
     }
 
     /// Returns the block, if `block_root` matches the cached item.
diff --git a/beacon_node/beacon_chain/src/errors.rs b/beacon_node/beacon_chain/src/errors.rs
index 0fc6a32435..f59fe55571 100644
--- a/beacon_node/beacon_chain/src/errors.rs
+++ b/beacon_node/beacon_chain/src/errors.rs
@@ -228,6 +228,10 @@ pub enum BeaconChainError {
     EmptyRpcCustodyColumns,
     AttestationError(AttestationError),
     AttestationCommitteeIndexNotSet,
+    InsufficientColumnsToReconstructBlobs {
+        columns_found: usize,
+    },
+    FailedToReconstructBlobs(String),
 }
 
 easy_from_to!(SlotProcessingError, BeaconChainError);
diff --git a/beacon_node/beacon_chain/src/eth1_chain.rs b/beacon_node/beacon_chain/src/eth1_chain.rs
index cb6e4c34f3..ad4f106517 100644
--- a/beacon_node/beacon_chain/src/eth1_chain.rs
+++ b/beacon_node/beacon_chain/src/eth1_chain.rs
@@ -153,7 +153,7 @@ fn get_sync_status<E: EthSpec>(
     // Lighthouse is "cached and ready" when it has cached enough blocks to cover the start of the
     // current voting period.
     let lighthouse_is_cached_and_ready =
-        latest_cached_block_timestamp.map_or(false, |t| t >= voting_target_timestamp);
+        latest_cached_block_timestamp.is_some_and(|t| t >= voting_target_timestamp);
 
     Some(Eth1SyncStatusData {
         head_block_number,
diff --git a/beacon_node/beacon_chain/src/events.rs b/beacon_node/beacon_chain/src/events.rs
index 267d56220c..8c342893ae 100644
--- a/beacon_node/beacon_chain/src/events.rs
+++ b/beacon_node/beacon_chain/src/events.rs
@@ -8,6 +8,7 @@ const DEFAULT_CHANNEL_CAPACITY: usize = 16;
 
 pub struct ServerSentEventHandler<E: EthSpec> {
     attestation_tx: Sender<EventKind<E>>,
+    single_attestation_tx: Sender<EventKind<E>>,
     block_tx: Sender<EventKind<E>>,
     blob_sidecar_tx: Sender<EventKind<E>>,
     finalized_tx: Sender<EventKind<E>>,
@@ -37,6 +38,7 @@ impl<E: EthSpec> ServerSentEventHandler<E> {
 
     pub fn new_with_capacity(log: Logger, capacity: usize) -> Self {
         let (attestation_tx, _) = broadcast::channel(capacity);
+        let (single_attestation_tx, _) = broadcast::channel(capacity);
         let (block_tx, _) = broadcast::channel(capacity);
         let (blob_sidecar_tx, _) = broadcast::channel(capacity);
         let (finalized_tx, _) = broadcast::channel(capacity);
@@ -56,6 +58,7 @@ impl<E: EthSpec> ServerSentEventHandler<E> {
 
         Self {
             attestation_tx,
+            single_attestation_tx,
             block_tx,
             blob_sidecar_tx,
             finalized_tx,
@@ -90,6 +93,10 @@ impl<E: EthSpec> ServerSentEventHandler<E> {
                 .attestation_tx
                 .send(kind)
                 .map(|count| log_count("attestation", count)),
+            EventKind::SingleAttestation(_) => self
+                .single_attestation_tx
+                .send(kind)
+                .map(|count| log_count("single_attestation", count)),
             EventKind::Block(_) => self
                 .block_tx
                 .send(kind)
@@ -164,6 +171,10 @@ impl<E: EthSpec> ServerSentEventHandler<E> {
         self.attestation_tx.subscribe()
     }
 
+    pub fn subscribe_single_attestation(&self) -> Receiver<EventKind<E>> {
+        self.single_attestation_tx.subscribe()
+    }
+
     pub fn subscribe_block(&self) -> Receiver<EventKind<E>> {
         self.block_tx.subscribe()
     }
@@ -232,6 +243,10 @@ impl<E: EthSpec> ServerSentEventHandler<E> {
         self.attestation_tx.receiver_count() > 0
     }
 
+    pub fn has_single_attestation_subscribers(&self) -> bool {
+        self.single_attestation_tx.receiver_count() > 0
+    }
+
     pub fn has_block_subscribers(&self) -> bool {
         self.block_tx.receiver_count() > 0
     }
diff --git a/beacon_node/beacon_chain/src/execution_payload.rs b/beacon_node/beacon_chain/src/execution_payload.rs
index ef4b81e9ff..9b44c47eeb 100644
--- a/beacon_node/beacon_chain/src/execution_payload.rs
+++ b/beacon_node/beacon_chain/src/execution_payload.rs
@@ -140,9 +140,9 @@ impl<T: BeaconChainTypes> PayloadNotifier<T> {
 /// contains a few extra checks by running `partially_verify_execution_payload` first:
 ///
 /// https://github.com/ethereum/consensus-specs/blob/v1.1.9/specs/bellatrix/beacon-chain.md#notify_new_payload
-async fn notify_new_payload<'a, T: BeaconChainTypes>(
+async fn notify_new_payload<T: BeaconChainTypes>(
     chain: &Arc<BeaconChain<T>>,
-    block: BeaconBlockRef<'a, T::EthSpec>,
+    block: BeaconBlockRef<'_, T::EthSpec>,
     il_transactions: InclusionListTransactions<T::EthSpec>,
 ) -> Result<PayloadVerificationStatus, BlockError> {
     let execution_layer = chain
@@ -258,9 +258,9 @@ async fn notify_new_payload<'a, T: BeaconChainTypes>(
 /// Equivalent to the `validate_merge_block` function in the merge Fork Choice Changes:
 ///
 /// https://github.com/ethereum/consensus-specs/blob/v1.1.5/specs/merge/fork-choice.md#validate_merge_block
-pub async fn validate_merge_block<'a, T: BeaconChainTypes>(
+pub async fn validate_merge_block<T: BeaconChainTypes>(
     chain: &Arc<BeaconChain<T>>,
-    block: BeaconBlockRef<'a, T::EthSpec>,
+    block: BeaconBlockRef<'_, T::EthSpec>,
     allow_optimistic_import: AllowOptimisticImport,
 ) -> Result<(), BlockError> {
     let spec = &chain.spec;
@@ -402,19 +402,15 @@ pub fn get_execution_payload<T: BeaconChainTypes>(
     let latest_execution_payload_header = state.latest_execution_payload_header()?;
     let latest_execution_payload_header_block_hash = latest_execution_payload_header.block_hash();
     let latest_execution_payload_header_gas_limit = latest_execution_payload_header.gas_limit();
-    let withdrawals = match state {
-        &BeaconState::Capella(_) | &BeaconState::Deneb(_) | &BeaconState::Electra(_) => {
-            Some(get_expected_withdrawals(state, spec)?.0.into())
-        }
-        &BeaconState::Bellatrix(_) => None,
-        // These shouldn't happen but they're here to make the pattern irrefutable
-        &BeaconState::Base(_) | &BeaconState::Altair(_) => None,
+    let withdrawals = if state.fork_name_unchecked().capella_enabled() {
+        Some(get_expected_withdrawals(state, spec)?.0.into())
+    } else {
+        None
     };
-    let parent_beacon_block_root = match state {
-        BeaconState::Deneb(_) | BeaconState::Electra(_) => Some(parent_block_root),
-        BeaconState::Bellatrix(_) | BeaconState::Capella(_) => None,
-        // These shouldn't happen but they're here to make the pattern irrefutable
-        BeaconState::Base(_) | BeaconState::Altair(_) => None,
+    let parent_beacon_block_root = if state.fork_name_unchecked().deneb_enabled() {
+        Some(parent_block_root)
+    } else {
+        None
     };
 
     // Spawn a task to obtain the execution payload from the EL via a series of async calls. The
diff --git a/beacon_node/beacon_chain/src/fetch_blobs.rs b/beacon_node/beacon_chain/src/fetch_blobs.rs
index f740b693fb..5bc2b92ec3 100644
--- a/beacon_node/beacon_chain/src/fetch_blobs.rs
+++ b/beacon_node/beacon_chain/src/fetch_blobs.rs
@@ -18,11 +18,11 @@ use slog::{debug, error, o, Logger};
 use ssz_types::FixedVector;
 use state_processing::per_block_processing::deneb::kzg_commitment_to_versioned_hash;
 use std::sync::Arc;
-use tokio::sync::mpsc::Receiver;
+use tokio::sync::oneshot;
 use types::blob_sidecar::{BlobSidecarError, FixedBlobSidecarList};
 use types::{
-    BeaconStateError, BlobSidecar, DataColumnSidecar, DataColumnSidecarList, EthSpec, FullPayload,
-    Hash256, SignedBeaconBlock, SignedBeaconBlockHeader,
+    BeaconStateError, BlobSidecar, ChainSpec, DataColumnSidecar, DataColumnSidecarList, EthSpec,
+    FullPayload, Hash256, SignedBeaconBlock, SignedBeaconBlockHeader,
 };
 
 pub enum BlobsOrDataColumns<T: BeaconChainTypes> {
@@ -112,6 +112,7 @@ pub async fn fetch_and_process_engine_blobs<T: BeaconChainTypes>(
         response,
         signed_block_header,
         &kzg_commitments_proof,
+        &chain.spec,
     )?;
 
     let num_fetched_blobs = fixed_blob_sidecar_list
@@ -162,6 +163,20 @@ pub async fn fetch_and_process_engine_blobs<T: BeaconChainTypes>(
             return Ok(None);
         }
 
+        if chain
+            .canonical_head
+            .fork_choice_read_lock()
+            .contains_block(&block_root)
+        {
+            // Avoid computing columns if block has already been imported.
+            debug!(
+                log,
+                "Ignoring EL blobs response";
+                "info" => "block has already been imported",
+            );
+            return Ok(None);
+        }
+
         let data_columns_receiver = spawn_compute_and_publish_data_columns_task(
             &chain,
             block.clone(),
@@ -212,9 +227,9 @@ fn spawn_compute_and_publish_data_columns_task<T: BeaconChainTypes>(
     blobs: FixedBlobSidecarList<T::EthSpec>,
     publish_fn: impl Fn(BlobsOrDataColumns<T>) + Send + 'static,
     log: Logger,
-) -> Receiver<Vec<Arc<DataColumnSidecar<T::EthSpec>>>> {
+) -> oneshot::Receiver<Vec<Arc<DataColumnSidecar<T::EthSpec>>>> {
     let chain_cloned = chain.clone();
-    let (data_columns_sender, data_columns_receiver) = tokio::sync::mpsc::channel(1);
+    let (data_columns_sender, data_columns_receiver) = oneshot::channel();
 
     chain.task_executor.spawn_blocking(
         move || {
@@ -247,18 +262,21 @@ fn spawn_compute_and_publish_data_columns_task<T: BeaconChainTypes>(
                 }
             };
 
-            if let Err(e) = data_columns_sender.try_send(all_data_columns.clone()) {
-                error!(log, "Failed to send computed data columns"; "error" => ?e);
+            if data_columns_sender.send(all_data_columns.clone()).is_err() {
+                // Data column receiver have been dropped - block may have already been imported.
+                // This race condition exists because gossip columns may arrive and trigger block
+                // import during the computation. Here we just drop the computed columns.
+                debug!(
+                    log,
+                    "Failed to send computed data columns";
+                );
+                return;
             };
 
-            // Check indices from cache before sending the columns, to make sure we don't
-            // publish components already seen on gossip.
-            let is_supernode = chain_cloned.data_availability_checker.is_supernode();
-
             // At the moment non supernodes are not required to publish any columns.
             // TODO(das): we could experiment with having full nodes publish their custodied
             // columns here.
-            if !is_supernode {
+            if !chain_cloned.data_availability_checker.is_supernode() {
                 return;
             }
 
@@ -275,8 +293,11 @@ fn build_blob_sidecars<E: EthSpec>(
     response: Vec<Option<BlobAndProofV1<E>>>,
     signed_block_header: SignedBeaconBlockHeader,
     kzg_commitments_inclusion_proof: &FixedVector<Hash256, E::KzgCommitmentsInclusionProofDepth>,
+    spec: &ChainSpec,
 ) -> Result<FixedBlobSidecarList<E>, FetchEngineBlobError> {
-    let mut fixed_blob_sidecar_list = FixedBlobSidecarList::default();
+    let epoch = block.epoch();
+    let mut fixed_blob_sidecar_list =
+        FixedBlobSidecarList::default(spec.max_blobs_per_block(epoch) as usize);
     for (index, blob_and_proof) in response
         .into_iter()
         .enumerate()
diff --git a/beacon_node/beacon_chain/src/fulu_readiness.rs b/beacon_node/beacon_chain/src/fulu_readiness.rs
new file mode 100644
index 0000000000..872fe58f2b
--- /dev/null
+++ b/beacon_node/beacon_chain/src/fulu_readiness.rs
@@ -0,0 +1,115 @@
+//! Provides tools for checking if a node is ready for the Fulu upgrade.
+
+use crate::{BeaconChain, BeaconChainTypes};
+use execution_layer::http::{ENGINE_GET_PAYLOAD_V4, ENGINE_NEW_PAYLOAD_V4};
+use serde::{Deserialize, Serialize};
+use std::fmt;
+use std::time::Duration;
+use types::*;
+
+/// The time before the Fulu fork when we will start issuing warnings about preparation.
+use super::bellatrix_readiness::SECONDS_IN_A_WEEK;
+pub const FULU_READINESS_PREPARATION_SECONDS: u64 = SECONDS_IN_A_WEEK * 2;
+pub const ENGINE_CAPABILITIES_REFRESH_INTERVAL: u64 = 300;
+
+#[derive(Debug, Serialize, Deserialize)]
+#[serde(rename_all = "snake_case")]
+#[serde(tag = "type")]
+pub enum FuluReadiness {
+    /// The execution engine is fulu-enabled (as far as we can tell)
+    Ready,
+    /// We are connected to an execution engine which doesn't support the V5 engine api methods
+    V5MethodsNotSupported { error: String },
+    /// The transition configuration with the EL failed, there might be a problem with
+    /// connectivity, authentication or a difference in configuration.
+    ExchangeCapabilitiesFailed { error: String },
+    /// The user has not configured an execution endpoint
+    NoExecutionEndpoint,
+}
+
+impl fmt::Display for FuluReadiness {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        match self {
+            FuluReadiness::Ready => {
+                write!(f, "This node appears ready for Fulu.")
+            }
+            FuluReadiness::ExchangeCapabilitiesFailed { error } => write!(
+                f,
+                "Could not exchange capabilities with the \
+                    execution endpoint: {}",
+                error
+            ),
+            FuluReadiness::NoExecutionEndpoint => write!(
+                f,
+                "The --execution-endpoint flag is not specified, this is a \
+                    requirement post-merge"
+            ),
+            FuluReadiness::V5MethodsNotSupported { error } => write!(
+                f,
+                "Execution endpoint does not support Fulu methods: {}",
+                error
+            ),
+        }
+    }
+}
+
+impl<T: BeaconChainTypes> BeaconChain<T> {
+    /// Returns `true` if fulu epoch is set and Fulu fork has occurred or will
+    /// occur within `FULU_READINESS_PREPARATION_SECONDS`
+    pub fn is_time_to_prepare_for_fulu(&self, current_slot: Slot) -> bool {
+        if let Some(fulu_epoch) = self.spec.fulu_fork_epoch {
+            let fulu_slot = fulu_epoch.start_slot(T::EthSpec::slots_per_epoch());
+            let fulu_readiness_preparation_slots =
+                FULU_READINESS_PREPARATION_SECONDS / self.spec.seconds_per_slot;
+            // Return `true` if Fulu has happened or is within the preparation time.
+            current_slot + fulu_readiness_preparation_slots > fulu_slot
+        } else {
+            // The Fulu fork epoch has not been defined yet, no need to prepare.
+            false
+        }
+    }
+
+    /// Attempts to connect to the EL and confirm that it is ready for fulu.
+    pub async fn check_fulu_readiness(&self) -> FuluReadiness {
+        if let Some(el) = self.execution_layer.as_ref() {
+            match el
+                .get_engine_capabilities(Some(Duration::from_secs(
+                    ENGINE_CAPABILITIES_REFRESH_INTERVAL,
+                )))
+                .await
+            {
+                Err(e) => {
+                    // The EL was either unreachable or responded with an error
+                    FuluReadiness::ExchangeCapabilitiesFailed {
+                        error: format!("{:?}", e),
+                    }
+                }
+                Ok(capabilities) => {
+                    let mut missing_methods = String::from("Required Methods Unsupported:");
+                    let mut all_good = true;
+                    // TODO(fulu) switch to v5 when the EL is ready
+                    if !capabilities.get_payload_v4 {
+                        missing_methods.push(' ');
+                        missing_methods.push_str(ENGINE_GET_PAYLOAD_V4);
+                        all_good = false;
+                    }
+                    if !capabilities.new_payload_v4 {
+                        missing_methods.push(' ');
+                        missing_methods.push_str(ENGINE_NEW_PAYLOAD_V4);
+                        all_good = false;
+                    }
+
+                    if all_good {
+                        FuluReadiness::Ready
+                    } else {
+                        FuluReadiness::V5MethodsNotSupported {
+                            error: missing_methods,
+                        }
+                    }
+                }
+            }
+        } else {
+            FuluReadiness::NoExecutionEndpoint
+        }
+    }
+}
diff --git a/beacon_node/beacon_chain/src/graffiti_calculator.rs b/beacon_node/beacon_chain/src/graffiti_calculator.rs
index 4373164d62..8692d374ed 100644
--- a/beacon_node/beacon_chain/src/graffiti_calculator.rs
+++ b/beacon_node/beacon_chain/src/graffiti_calculator.rs
@@ -293,10 +293,7 @@ mod tests {
             .await
             .unwrap();
 
-        let version_bytes = std::cmp::min(
-            lighthouse_version::VERSION.as_bytes().len(),
-            GRAFFITI_BYTES_LEN,
-        );
+        let version_bytes = std::cmp::min(lighthouse_version::VERSION.len(), GRAFFITI_BYTES_LEN);
         // grab the slice of the graffiti that corresponds to the lighthouse version
         let graffiti_slice =
             &harness.chain.graffiti_calculator.get_graffiti(None).await.0[..version_bytes];
@@ -361,7 +358,7 @@ mod tests {
 
         let graffiti_str = "nice graffiti bro";
         let mut graffiti_bytes = [0u8; GRAFFITI_BYTES_LEN];
-        graffiti_bytes[..graffiti_str.as_bytes().len()].copy_from_slice(graffiti_str.as_bytes());
+        graffiti_bytes[..graffiti_str.len()].copy_from_slice(graffiti_str.as_bytes());
 
         let found_graffiti = harness
             .chain
diff --git a/beacon_node/beacon_chain/src/historical_blocks.rs b/beacon_node/beacon_chain/src/historical_blocks.rs
index ddae54f464..e22ec95a79 100644
--- a/beacon_node/beacon_chain/src/historical_blocks.rs
+++ b/beacon_node/beacon_chain/src/historical_blocks.rs
@@ -10,10 +10,7 @@ use std::borrow::Cow;
 use std::iter;
 use std::time::Duration;
 use store::metadata::DataColumnInfo;
-use store::{
-    get_key_for_col, AnchorInfo, BlobInfo, DBColumn, Error as StoreError, KeyValueStore,
-    KeyValueStoreOp,
-};
+use store::{AnchorInfo, BlobInfo, DBColumn, Error as StoreError, KeyValueStore, KeyValueStoreOp};
 use strum::IntoStaticStr;
 use types::{FixedBytesExtended, Hash256, Slot};
 
@@ -153,7 +150,8 @@ impl<T: BeaconChainTypes> BeaconChain<T> {
             // Store block roots, including at all skip slots in the freezer DB.
             for slot in (block.slot().as_u64()..prev_block_slot.as_u64()).rev() {
                 cold_batch.push(KeyValueStoreOp::PutKeyValue(
-                    get_key_for_col(DBColumn::BeaconBlockRoots.into(), &slot.to_be_bytes()),
+                    DBColumn::BeaconBlockRoots,
+                    slot.to_be_bytes().to_vec(),
                     block_root.as_slice().to_vec(),
                 ));
             }
@@ -169,7 +167,8 @@ impl<T: BeaconChainTypes> BeaconChain<T> {
                 let genesis_slot = self.spec.genesis_slot;
                 for slot in genesis_slot.as_u64()..prev_block_slot.as_u64() {
                     cold_batch.push(KeyValueStoreOp::PutKeyValue(
-                        get_key_for_col(DBColumn::BeaconBlockRoots.into(), &slot.to_be_bytes()),
+                        DBColumn::BeaconBlockRoots,
+                        slot.to_be_bytes().to_vec(),
                         self.genesis_block_root.as_slice().to_vec(),
                     ));
                 }
diff --git a/beacon_node/beacon_chain/src/kzg_utils.rs b/beacon_node/beacon_chain/src/kzg_utils.rs
index 1680c0298d..06cce14144 100644
--- a/beacon_node/beacon_chain/src/kzg_utils.rs
+++ b/beacon_node/beacon_chain/src/kzg_utils.rs
@@ -7,8 +7,9 @@ use std::sync::Arc;
 use types::beacon_block_body::KzgCommitments;
 use types::data_column_sidecar::{Cell, DataColumn, DataColumnSidecarError};
 use types::{
-    Blob, ChainSpec, ColumnIndex, DataColumnSidecar, DataColumnSidecarList, EthSpec, Hash256,
-    KzgCommitment, KzgProof, KzgProofs, SignedBeaconBlock, SignedBeaconBlockHeader,
+    Blob, BlobSidecar, BlobSidecarList, ChainSpec, ColumnIndex, DataColumnSidecar,
+    DataColumnSidecarList, EthSpec, Hash256, KzgCommitment, KzgProof, KzgProofs, SignedBeaconBlock,
+    SignedBeaconBlockHeader, SignedBlindedBeaconBlock,
 };
 
 /// Converts a blob ssz List object to an array to be used with the kzg
@@ -185,17 +186,19 @@ pub fn blobs_to_data_column_sidecars<E: EthSpec>(
     .map_err(DataColumnSidecarError::BuildSidecarFailed)
 }
 
-fn build_data_column_sidecars<E: EthSpec>(
+pub(crate) fn build_data_column_sidecars<E: EthSpec>(
     kzg_commitments: KzgCommitments<E>,
     kzg_commitments_inclusion_proof: FixedVector<Hash256, E::KzgCommitmentsInclusionProofDepth>,
     signed_block_header: SignedBeaconBlockHeader,
     blob_cells_and_proofs_vec: Vec<CellsAndKzgProofs>,
     spec: &ChainSpec,
 ) -> Result<DataColumnSidecarList<E>, String> {
-    let number_of_columns = spec.number_of_columns;
-    let mut columns = vec![Vec::with_capacity(E::max_blobs_per_block()); number_of_columns];
-    let mut column_kzg_proofs =
-        vec![Vec::with_capacity(E::max_blobs_per_block()); number_of_columns];
+    let number_of_columns = spec.number_of_columns as usize;
+    let max_blobs_per_block = spec
+        .max_blobs_per_block(signed_block_header.message.slot.epoch(E::slots_per_epoch()))
+        as usize;
+    let mut columns = vec![Vec::with_capacity(max_blobs_per_block); number_of_columns];
+    let mut column_kzg_proofs = vec![Vec::with_capacity(max_blobs_per_block); number_of_columns];
 
     for (blob_cells, blob_cell_proofs) in blob_cells_and_proofs_vec {
         // we iterate over each column, and we construct the column from "top to bottom",
@@ -243,6 +246,85 @@ fn build_data_column_sidecars<E: EthSpec>(
     Ok(sidecars)
 }
 
+/// Reconstruct blobs from a subset of data column sidecars (requires at least 50%).
+///
+/// If `blob_indices_opt` is `None`, this function attempts to reconstruct all blobs associated
+/// with the block.
+pub fn reconstruct_blobs<E: EthSpec>(
+    kzg: &Kzg,
+    data_columns: &[Arc<DataColumnSidecar<E>>],
+    blob_indices_opt: Option<Vec<u64>>,
+    signed_block: &SignedBlindedBeaconBlock<E>,
+    spec: &ChainSpec,
+) -> Result<BlobSidecarList<E>, String> {
+    // The data columns are from the database, so we assume their correctness.
+    let first_data_column = data_columns
+        .first()
+        .ok_or("data_columns should have at least one element".to_string())?;
+
+    let blob_indices: Vec<usize> = match blob_indices_opt {
+        Some(indices) => indices.into_iter().map(|i| i as usize).collect(),
+        None => {
+            let num_of_blobs = first_data_column.kzg_commitments.len();
+            (0..num_of_blobs).collect()
+        }
+    };
+
+    let blob_sidecars = blob_indices
+        .into_par_iter()
+        .map(|row_index| {
+            let mut cells: Vec<KzgCellRef> = vec![];
+            let mut cell_ids: Vec<u64> = vec![];
+            for data_column in data_columns {
+                let cell = data_column
+                    .column
+                    .get(row_index)
+                    .ok_or(format!("Missing data column at row index {row_index}"))
+                    .and_then(|cell| {
+                        ssz_cell_to_crypto_cell::<E>(cell).map_err(|e| format!("{e:?}"))
+                    })?;
+
+                cells.push(cell);
+                cell_ids.push(data_column.index);
+            }
+
+            let (cells, _kzg_proofs) = kzg
+                .recover_cells_and_compute_kzg_proofs(&cell_ids, &cells)
+                .map_err(|e| format!("Failed to recover cells and compute KZG proofs: {e:?}"))?;
+
+            let num_cells_original_blob = cells.len() / 2;
+            let blob_bytes = cells
+                .into_iter()
+                .take(num_cells_original_blob)
+                .flat_map(|cell| cell.into_iter())
+                .collect();
+
+            let blob = Blob::<E>::new(blob_bytes).map_err(|e| format!("{e:?}"))?;
+            let kzg_commitment = first_data_column
+                .kzg_commitments
+                .get(row_index)
+                .ok_or(format!("Missing KZG commitment for blob {row_index}"))?;
+            let kzg_proof = compute_blob_kzg_proof::<E>(kzg, &blob, *kzg_commitment)
+                .map_err(|e| format!("{e:?}"))?;
+
+            BlobSidecar::<E>::new_with_existing_proof(
+                row_index,
+                blob,
+                signed_block,
+                first_data_column.signed_block_header.clone(),
+                &first_data_column.kzg_commitments_inclusion_proof,
+                kzg_proof,
+            )
+            .map(Arc::new)
+            .map_err(|e| format!("{e:?}"))
+        })
+        .collect::<Result<Vec<_>, _>>()?;
+
+    let max_blobs = spec.max_blobs_per_block(signed_block.epoch()) as usize;
+
+    BlobSidecarList::new(blob_sidecars, max_blobs).map_err(|e| format!("{e:?}"))
+}
+
 /// Reconstruct all data columns from a subset of data column sidecars (requires at least 50%).
 pub fn reconstruct_data_columns<E: EthSpec>(
     kzg: &Kzg,
@@ -265,7 +347,7 @@ pub fn reconstruct_data_columns<E: EthSpec>(
                 for data_column in data_columns {
                     let cell = data_column.column.get(row_index).ok_or(
                         KzgError::InconsistentArrayLength(format!(
-                            "Missing data column at index {row_index}"
+                            "Missing data column at row index {row_index}"
                         )),
                     )?;
 
@@ -289,12 +371,16 @@ pub fn reconstruct_data_columns<E: EthSpec>(
 
 #[cfg(test)]
 mod test {
-    use crate::kzg_utils::{blobs_to_data_column_sidecars, reconstruct_data_columns};
+    use crate::kzg_utils::{
+        blobs_to_data_column_sidecars, reconstruct_blobs, reconstruct_data_columns,
+    };
     use bls::Signature;
+    use eth2::types::BlobsBundle;
+    use execution_layer::test_utils::generate_blobs;
     use kzg::{trusted_setup::get_trusted_setup, Kzg, KzgCommitment, TrustedSetup};
     use types::{
-        beacon_block_body::KzgCommitments, BeaconBlock, BeaconBlockDeneb, Blob, BlobsList,
-        ChainSpec, EmptyBlock, EthSpec, MainnetEthSpec, SignedBeaconBlock,
+        beacon_block_body::KzgCommitments, BeaconBlock, BeaconBlockDeneb, BlobsList, ChainSpec,
+        EmptyBlock, EthSpec, MainnetEthSpec, SignedBeaconBlock,
     };
 
     type E = MainnetEthSpec;
@@ -308,6 +394,7 @@ mod test {
         test_build_data_columns_empty(&kzg, &spec);
         test_build_data_columns(&kzg, &spec);
         test_reconstruct_data_columns(&kzg, &spec);
+        test_reconstruct_blobs_from_data_columns(&kzg, &spec);
     }
 
     #[track_caller]
@@ -341,7 +428,7 @@ mod test {
             .kzg_commitments_merkle_proof()
             .unwrap();
 
-        assert_eq!(column_sidecars.len(), spec.number_of_columns);
+        assert_eq!(column_sidecars.len(), spec.number_of_columns as usize);
         for (idx, col_sidecar) in column_sidecars.iter().enumerate() {
             assert_eq!(col_sidecar.index, idx as u64);
 
@@ -374,11 +461,42 @@ mod test {
         )
         .unwrap();
 
-        for i in 0..spec.number_of_columns {
+        for i in 0..spec.number_of_columns as usize {
             assert_eq!(reconstructed_columns.get(i), column_sidecars.get(i), "{i}");
         }
     }
 
+    #[track_caller]
+    fn test_reconstruct_blobs_from_data_columns(kzg: &Kzg, spec: &ChainSpec) {
+        let num_of_blobs = 6;
+        let (signed_block, blobs) = create_test_block_and_blobs::<E>(num_of_blobs, spec);
+        let blob_refs = blobs.iter().collect::<Vec<_>>();
+        let column_sidecars =
+            blobs_to_data_column_sidecars(&blob_refs, &signed_block, kzg, spec).unwrap();
+
+        // Now reconstruct
+        let signed_blinded_block = signed_block.into();
+        let blob_indices = vec![3, 4, 5];
+        let reconstructed_blobs = reconstruct_blobs(
+            kzg,
+            &column_sidecars.iter().as_slice()[0..column_sidecars.len() / 2],
+            Some(blob_indices.clone()),
+            &signed_blinded_block,
+            spec,
+        )
+        .unwrap();
+
+        for i in blob_indices {
+            let reconstructed_blob = &reconstructed_blobs
+                .iter()
+                .find(|sidecar| sidecar.index == i)
+                .map(|sidecar| sidecar.blob.clone())
+                .expect("reconstructed blob should exist");
+            let original_blob = blobs.get(i as usize).unwrap();
+            assert_eq!(reconstructed_blob, original_blob, "{i}");
+        }
+    }
+
     fn get_kzg() -> Kzg {
         let trusted_setup: TrustedSetup = serde_json::from_reader(get_trusted_setup().as_slice())
             .map_err(|e| format!("Unable to read trusted setup file: {}", e))
@@ -397,12 +515,20 @@ mod test {
             KzgCommitments::<E>::new(vec![KzgCommitment::empty_for_testing(); num_of_blobs])
                 .unwrap();
 
-        let signed_block = SignedBeaconBlock::from_block(block, Signature::empty());
+        let mut signed_block = SignedBeaconBlock::from_block(block, Signature::empty());
 
-        let blobs = (0..num_of_blobs)
-            .map(|_| Blob::<E>::default())
-            .collect::<Vec<_>>()
-            .into();
+        let (blobs_bundle, _) = generate_blobs::<E>(num_of_blobs).unwrap();
+        let BlobsBundle {
+            blobs,
+            commitments,
+            proofs: _,
+        } = blobs_bundle;
+
+        *signed_block
+            .message_mut()
+            .body_mut()
+            .blob_kzg_commitments_mut()
+            .unwrap() = commitments;
 
         (signed_block, blobs)
     }
diff --git a/beacon_node/beacon_chain/src/lib.rs b/beacon_node/beacon_chain/src/lib.rs
index 1facde02c4..fe03420736 100644
--- a/beacon_node/beacon_chain/src/lib.rs
+++ b/beacon_node/beacon_chain/src/lib.rs
@@ -31,6 +31,7 @@ pub mod execution_payload;
 pub mod fetch_blobs;
 pub mod fork_choice_signal;
 pub mod fork_revert;
+pub mod fulu_readiness;
 pub mod graffiti_calculator;
 mod head_tracker;
 pub mod historical_blocks;
@@ -78,7 +79,7 @@ pub use beacon_fork_choice_store::{BeaconForkChoiceStore, Error as ForkChoiceSto
 pub use block_verification::{
     build_blob_data_column_sidecars, get_block_root, BlockError, ExecutionPayloadError,
     ExecutionPendingBlock, GossipVerifiedBlock, IntoExecutionPendingBlock, IntoGossipVerifiedBlock,
-    PayloadVerificationOutcome, PayloadVerificationStatus,
+    InvalidSignature, PayloadVerificationOutcome, PayloadVerificationStatus,
 };
 pub use block_verification_types::AvailabilityPendingExecutedBlock;
 pub use block_verification_types::ExecutedBlock;
diff --git a/beacon_node/beacon_chain/src/metrics.rs b/beacon_node/beacon_chain/src/metrics.rs
index c6aa9fbcac..ae3add7f03 100644
--- a/beacon_node/beacon_chain/src/metrics.rs
+++ b/beacon_node/beacon_chain/src/metrics.rs
@@ -1656,7 +1656,7 @@ pub static BLOB_SIDECAR_INCLUSION_PROOF_COMPUTATION: LazyLock<Result<Histogram>>
     });
 pub static DATA_COLUMN_SIDECAR_COMPUTATION: LazyLock<Result<HistogramVec>> = LazyLock::new(|| {
     try_create_histogram_vec_with_buckets(
-        "data_column_sidecar_computation_seconds",
+        "beacon_data_column_sidecar_computation_seconds",
         "Time taken to compute data column sidecar, including cells, proofs and inclusion proof",
         Ok(vec![0.1, 0.15, 0.25, 0.35, 0.5, 0.7, 1.0, 2.5, 5.0, 10.0]),
         &["blob_count"],
@@ -1665,7 +1665,7 @@ pub static DATA_COLUMN_SIDECAR_COMPUTATION: LazyLock<Result<HistogramVec>> = Laz
 pub static DATA_COLUMN_SIDECAR_INCLUSION_PROOF_VERIFICATION: LazyLock<Result<Histogram>> =
     LazyLock::new(|| {
         try_create_histogram(
-            "data_column_sidecar_inclusion_proof_verification_seconds",
+            "beacon_data_column_sidecar_inclusion_proof_verification_seconds",
             "Time taken to verify data_column sidecar inclusion proof",
         )
     });
@@ -1693,7 +1693,7 @@ pub static DATA_COLUMN_SIDECAR_GOSSIP_VERIFICATION_TIMES: LazyLock<Result<Histog
 pub static DATA_COLUMNS_SIDECAR_PROCESSING_SUCCESSES: LazyLock<Result<IntCounter>> =
     LazyLock::new(|| {
         try_create_int_counter(
-            "beacon_blobs_column_sidecar_processing_successes_total",
+            "beacon_data_column_sidecar_processing_successes_total",
             "Number of data column sidecars verified for gossip",
         )
     });
@@ -1847,7 +1847,7 @@ pub static KZG_VERIFICATION_BATCH_TIMES: LazyLock<Result<Histogram>> = LazyLock:
 pub static KZG_VERIFICATION_DATA_COLUMN_SINGLE_TIMES: LazyLock<Result<Histogram>> =
     LazyLock::new(|| {
         try_create_histogram_with_buckets(
-            "kzg_verification_data_column_single_seconds",
+            "beacon_kzg_verification_data_column_single_seconds",
             "Runtime of single data column kzg verification",
             Ok(vec![
                 0.0005, 0.001, 0.0015, 0.002, 0.003, 0.004, 0.005, 0.007, 0.01, 0.02, 0.05,
@@ -1857,7 +1857,7 @@ pub static KZG_VERIFICATION_DATA_COLUMN_SINGLE_TIMES: LazyLock<Result<Histogram>
 pub static KZG_VERIFICATION_DATA_COLUMN_BATCH_TIMES: LazyLock<Result<Histogram>> =
     LazyLock::new(|| {
         try_create_histogram_with_buckets(
-            "kzg_verification_data_column_batch_seconds",
+            "beacon_kzg_verification_data_column_batch_seconds",
             "Runtime of batched data column kzg verification",
             Ok(vec![
                 0.002, 0.004, 0.006, 0.008, 0.01, 0.012, 0.015, 0.02, 0.03, 0.05, 0.07,
@@ -1910,14 +1910,14 @@ pub static DATA_AVAILABILITY_OVERFLOW_STORE_CACHE_SIZE: LazyLock<Result<IntGauge
 pub static DATA_AVAILABILITY_RECONSTRUCTION_TIME: LazyLock<Result<Histogram>> =
     LazyLock::new(|| {
         try_create_histogram(
-            "data_availability_reconstruction_time_seconds",
+            "beacon_data_availability_reconstruction_time_seconds",
             "Time taken to reconstruct columns",
         )
     });
 pub static DATA_AVAILABILITY_RECONSTRUCTED_COLUMNS: LazyLock<Result<IntCounter>> =
     LazyLock::new(|| {
         try_create_int_counter(
-            "data_availability_reconstructed_columns_total",
+            "beacon_data_availability_reconstructed_columns_total",
             "Total count of reconstructed columns",
         )
     });
@@ -1925,7 +1925,7 @@ pub static DATA_AVAILABILITY_RECONSTRUCTED_COLUMNS: LazyLock<Result<IntCounter>>
 pub static KZG_DATA_COLUMN_RECONSTRUCTION_ATTEMPTS: LazyLock<Result<IntCounter>> =
     LazyLock::new(|| {
         try_create_int_counter(
-            "kzg_data_column_reconstruction_attempts",
+            "beacon_kzg_data_column_reconstruction_attempts",
             "Count of times data column reconstruction has been attempted",
         )
     });
@@ -1933,7 +1933,7 @@ pub static KZG_DATA_COLUMN_RECONSTRUCTION_ATTEMPTS: LazyLock<Result<IntCounter>>
 pub static KZG_DATA_COLUMN_RECONSTRUCTION_FAILURES: LazyLock<Result<IntCounter>> =
     LazyLock::new(|| {
         try_create_int_counter(
-            "kzg_data_column_reconstruction_failures",
+            "beacon_kzg_data_column_reconstruction_failures",
             "Count of times data column reconstruction has failed",
         )
     });
@@ -1941,7 +1941,7 @@ pub static KZG_DATA_COLUMN_RECONSTRUCTION_FAILURES: LazyLock<Result<IntCounter>>
 pub static KZG_DATA_COLUMN_RECONSTRUCTION_INCOMPLETE_TOTAL: LazyLock<Result<IntCounterVec>> =
     LazyLock::new(|| {
         try_create_int_counter_vec(
-            "kzg_data_column_reconstruction_incomplete_total",
+            "beacon_kzg_data_column_reconstruction_incomplete_total",
             "Count of times data column reconstruction attempts did not result in an import",
             &["reason"],
         )
diff --git a/beacon_node/beacon_chain/src/observed_aggregates.rs b/beacon_node/beacon_chain/src/observed_aggregates.rs
index dec012fb92..20ed36ace7 100644
--- a/beacon_node/beacon_chain/src/observed_aggregates.rs
+++ b/beacon_node/beacon_chain/src/observed_aggregates.rs
@@ -293,7 +293,7 @@ impl<I> SlotHashSet<I> {
         Ok(self
             .map
             .get(&root)
-            .map_or(false, |agg| agg.iter().any(|val| item.is_subset(val))))
+            .is_some_and(|agg| agg.iter().any(|val| item.is_subset(val))))
     }
 
     /// The number of observed items in `self`.
diff --git a/beacon_node/beacon_chain/src/observed_attesters.rs b/beacon_node/beacon_chain/src/observed_attesters.rs
index efb95f57a9..5bba8e4d8e 100644
--- a/beacon_node/beacon_chain/src/observed_attesters.rs
+++ b/beacon_node/beacon_chain/src/observed_attesters.rs
@@ -130,7 +130,7 @@ impl Item<()> for EpochBitfield {
     fn get(&self, validator_index: usize) -> Option<()> {
         self.bitfield
             .get(validator_index)
-            .map_or(false, |bit| *bit)
+            .is_some_and(|bit| *bit)
             .then_some(())
     }
 }
@@ -336,7 +336,7 @@ impl<T: Item<()>, E: EthSpec> AutoPruningEpochContainer<T, E> {
         let exists = self
             .items
             .get(&epoch)
-            .map_or(false, |item| item.get(validator_index).is_some());
+            .is_some_and(|item| item.get(validator_index).is_some());
 
         Ok(exists)
     }
diff --git a/beacon_node/beacon_chain/src/observed_data_sidecars.rs b/beacon_node/beacon_chain/src/observed_data_sidecars.rs
index 53f8c71f54..1ca6c03f00 100644
--- a/beacon_node/beacon_chain/src/observed_data_sidecars.rs
+++ b/beacon_node/beacon_chain/src/observed_data_sidecars.rs
@@ -24,7 +24,7 @@ pub trait ObservableDataSidecar {
     fn slot(&self) -> Slot;
     fn block_proposer_index(&self) -> u64;
     fn index(&self) -> u64;
-    fn max_num_of_items(spec: &ChainSpec) -> usize;
+    fn max_num_of_items(spec: &ChainSpec, slot: Slot) -> usize;
 }
 
 impl<E: EthSpec> ObservableDataSidecar for BlobSidecar<E> {
@@ -40,8 +40,8 @@ impl<E: EthSpec> ObservableDataSidecar for BlobSidecar<E> {
         self.index
     }
 
-    fn max_num_of_items(_spec: &ChainSpec) -> usize {
-        E::max_blobs_per_block()
+    fn max_num_of_items(spec: &ChainSpec, slot: Slot) -> usize {
+        spec.max_blobs_per_block(slot.epoch(E::slots_per_epoch())) as usize
     }
 }
 
@@ -58,8 +58,8 @@ impl<E: EthSpec> ObservableDataSidecar for DataColumnSidecar<E> {
         self.index
     }
 
-    fn max_num_of_items(spec: &ChainSpec) -> usize {
-        spec.number_of_columns
+    fn max_num_of_items(spec: &ChainSpec, _slot: Slot) -> usize {
+        spec.number_of_columns as usize
     }
 }
 
@@ -103,7 +103,9 @@ impl<T: ObservableDataSidecar> ObservedDataSidecars<T> {
                 slot: data_sidecar.slot(),
                 proposer: data_sidecar.block_proposer_index(),
             })
-            .or_insert_with(|| HashSet::with_capacity(T::max_num_of_items(&self.spec)));
+            .or_insert_with(|| {
+                HashSet::with_capacity(T::max_num_of_items(&self.spec, data_sidecar.slot()))
+            });
         let did_not_exist = data_indices.insert(data_sidecar.index());
 
         Ok(!did_not_exist)
@@ -118,12 +120,12 @@ impl<T: ObservableDataSidecar> ObservedDataSidecars<T> {
                 slot: data_sidecar.slot(),
                 proposer: data_sidecar.block_proposer_index(),
             })
-            .map_or(false, |indices| indices.contains(&data_sidecar.index()));
+            .is_some_and(|indices| indices.contains(&data_sidecar.index()));
         Ok(is_known)
     }
 
     fn sanitize_data_sidecar(&self, data_sidecar: &T) -> Result<(), Error> {
-        if data_sidecar.index() >= T::max_num_of_items(&self.spec) as u64 {
+        if data_sidecar.index() >= T::max_num_of_items(&self.spec, data_sidecar.slot()) as u64 {
             return Err(Error::InvalidDataIndex(data_sidecar.index()));
         }
         let finalized_slot = self.finalized_slot;
@@ -179,7 +181,7 @@ mod tests {
     use crate::test_utils::test_spec;
     use bls::Hash256;
     use std::sync::Arc;
-    use types::MainnetEthSpec;
+    use types::{Epoch, MainnetEthSpec};
 
     type E = MainnetEthSpec;
 
@@ -333,7 +335,7 @@ mod tests {
     #[test]
     fn simple_observations() {
         let spec = Arc::new(test_spec::<E>());
-        let mut cache = ObservedDataSidecars::<BlobSidecar<E>>::new(spec);
+        let mut cache = ObservedDataSidecars::<BlobSidecar<E>>::new(spec.clone());
 
         // Slot 0, index 0
         let proposer_index_a = 420;
@@ -489,7 +491,7 @@ mod tests {
         );
 
         // Try adding an out of bounds index
-        let invalid_index = E::max_blobs_per_block() as u64;
+        let invalid_index = spec.max_blobs_per_block(Epoch::new(0));
         let sidecar_d = get_blob_sidecar(0, proposer_index_a, invalid_index);
         assert_eq!(
             cache.observe_sidecar(&sidecar_d),
diff --git a/beacon_node/beacon_chain/src/schema_change/migration_schema_v21.rs b/beacon_node/beacon_chain/src/schema_change/migration_schema_v21.rs
index fcc8b9884a..f02f5ee6f3 100644
--- a/beacon_node/beacon_chain/src/schema_change/migration_schema_v21.rs
+++ b/beacon_node/beacon_chain/src/schema_change/migration_schema_v21.rs
@@ -3,9 +3,7 @@ use crate::validator_pubkey_cache::DatabasePubkey;
 use slog::{info, Logger};
 use ssz::{Decode, Encode};
 use std::sync::Arc;
-use store::{
-    get_key_for_col, DBColumn, Error, HotColdDB, KeyValueStore, KeyValueStoreOp, StoreItem,
-};
+use store::{DBColumn, Error, HotColdDB, KeyValueStore, KeyValueStoreOp, StoreItem};
 use types::{Hash256, PublicKey};
 
 const LOG_EVERY: usize = 200_000;
@@ -62,9 +60,9 @@ pub fn downgrade_from_v21<T: BeaconChainTypes>(
             message: format!("{e:?}"),
         })?;
 
-        let db_key = get_key_for_col(DBColumn::PubkeyCache.into(), key.as_slice());
         ops.push(KeyValueStoreOp::PutKeyValue(
-            db_key,
+            DBColumn::PubkeyCache,
+            key.as_slice().to_vec(),
             pubkey_bytes.as_ssz_bytes(),
         ));
 
diff --git a/beacon_node/beacon_chain/src/schema_change/migration_schema_v22.rs b/beacon_node/beacon_chain/src/schema_change/migration_schema_v22.rs
index c34512eded..982c3ded46 100644
--- a/beacon_node/beacon_chain/src/schema_change/migration_schema_v22.rs
+++ b/beacon_node/beacon_chain/src/schema_change/migration_schema_v22.rs
@@ -4,7 +4,6 @@ use std::sync::Arc;
 use store::chunked_iter::ChunkedVectorIter;
 use store::{
     chunked_vector::BlockRootsChunked,
-    get_key_for_col,
     metadata::{
         SchemaVersion, ANCHOR_FOR_ARCHIVE_NODE, ANCHOR_UNINITIALIZED, STATE_UPPER_LIMIT_NO_RETAIN,
     },
@@ -21,7 +20,7 @@ fn load_old_schema_frozen_state<T: BeaconChainTypes>(
 ) -> Result<Option<BeaconState<T::EthSpec>>, Error> {
     let Some(partial_state_bytes) = db
         .cold_db
-        .get_bytes(DBColumn::BeaconState.into(), state_root.as_slice())?
+        .get_bytes(DBColumn::BeaconState, state_root.as_slice())?
     else {
         return Ok(None);
     };
@@ -136,10 +135,7 @@ pub fn delete_old_schema_freezer_data<T: BeaconChainTypes>(
     for column in columns {
         for res in db.cold_db.iter_column_keys::<Vec<u8>>(column) {
             let key = res?;
-            cold_ops.push(KeyValueStoreOp::DeleteKey(get_key_for_col(
-                column.as_str(),
-                &key,
-            )));
+            cold_ops.push(KeyValueStoreOp::DeleteKey(column, key));
         }
     }
     let delete_ops = cold_ops.len();
@@ -175,7 +171,8 @@ pub fn write_new_schema_block_roots<T: BeaconChainTypes>(
     // Store the genesis block root if it would otherwise not be stored.
     if oldest_block_slot != 0 {
         cold_ops.push(KeyValueStoreOp::PutKeyValue(
-            get_key_for_col(DBColumn::BeaconBlockRoots.into(), &0u64.to_be_bytes()),
+            DBColumn::BeaconBlockRoots,
+            0u64.to_be_bytes().to_vec(),
             genesis_block_root.as_slice().to_vec(),
         ));
     }
@@ -192,10 +189,8 @@ pub fn write_new_schema_block_roots<T: BeaconChainTypes>(
     // OK to hold these in memory (10M slots * 43 bytes per KV ~= 430 MB).
     for (i, (slot, block_root)) in block_root_iter.enumerate() {
         cold_ops.push(KeyValueStoreOp::PutKeyValue(
-            get_key_for_col(
-                DBColumn::BeaconBlockRoots.into(),
-                &(slot as u64).to_be_bytes(),
-            ),
+            DBColumn::BeaconBlockRoots,
+            slot.to_be_bytes().to_vec(),
             block_root.as_slice().to_vec(),
         ));
 
diff --git a/beacon_node/beacon_chain/src/shuffling_cache.rs b/beacon_node/beacon_chain/src/shuffling_cache.rs
index da1d60db17..67ca72254b 100644
--- a/beacon_node/beacon_chain/src/shuffling_cache.rs
+++ b/beacon_node/beacon_chain/src/shuffling_cache.rs
@@ -253,7 +253,7 @@ impl BlockShufflingIds {
         } else if self
             .previous
             .as_ref()
-            .map_or(false, |id| id.shuffling_epoch == epoch)
+            .is_some_and(|id| id.shuffling_epoch == epoch)
         {
             self.previous.clone()
         } else if epoch == self.next.shuffling_epoch {
diff --git a/beacon_node/beacon_chain/src/test_utils.rs b/beacon_node/beacon_chain/src/test_utils.rs
index 093ee0c44b..4526b2b360 100644
--- a/beacon_node/beacon_chain/src/test_utils.rs
+++ b/beacon_node/beacon_chain/src/test_utils.rs
@@ -1,8 +1,9 @@
+use crate::blob_verification::GossipVerifiedBlob;
 use crate::block_verification_types::{AsBlock, RpcBlock};
-use crate::kzg_utils::blobs_to_data_column_sidecars;
+use crate::data_column_verification::CustodyDataColumn;
+use crate::kzg_utils::build_data_column_sidecars;
 use crate::observed_operations::ObservationOutcome;
 pub use crate::persisted_beacon_chain::PersistedBeaconChain;
-use crate::BeaconBlockResponseWrapper;
 pub use crate::{
     beacon_chain::{BEACON_CHAIN_DB_KEY, ETH1_CACHE_DB_KEY, FORK_CHOICE_DB_KEY, OP_POOL_DB_KEY},
     migrate::MigratorConfig,
@@ -16,6 +17,7 @@ use crate::{
     BeaconChain, BeaconChainTypes, BlockError, ChainConfig, ServerSentEventHandler,
     StateSkipConfig,
 };
+use crate::{get_block_root, BeaconBlockResponseWrapper};
 use bls::get_withdrawal_credentials;
 use eth2::types::SignedBlockContentsTuple;
 use execution_layer::test_utils::generate_genesis_header;
@@ -56,7 +58,8 @@ use std::str::FromStr;
 use std::sync::atomic::{AtomicUsize, Ordering};
 use std::sync::{Arc, LazyLock};
 use std::time::Duration;
-use store::{config::StoreConfig, HotColdDB, ItemStore, LevelDB, MemoryStore};
+use store::database::interface::BeaconNodeBackend;
+use store::{config::StoreConfig, HotColdDB, ItemStore, MemoryStore};
 use task_executor::TaskExecutor;
 use task_executor::{test_utils::TestRuntime, ShutdownReason};
 use tree_hash::TreeHash;
@@ -73,6 +76,11 @@ pub const FORK_NAME_ENV_VAR: &str = "FORK_NAME";
 // Environment variable to read if `ci_logger` feature is enabled.
 pub const CI_LOGGER_DIR_ENV_VAR: &str = "CI_LOGGER_DIR";
 
+// Pre-computed data column sidecar using a single static blob from:
+// `beacon_node/execution_layer/src/test_utils/fixtures/mainnet/test_blobs_bundle.ssz`
+const TEST_DATA_COLUMN_SIDECARS_SSZ: &[u8] =
+    include_bytes!("test_utils/fixtures/test_data_column_sidecars.ssz");
+
 // Default target aggregators to set during testing, this ensures an aggregator at each slot.
 //
 // You should mutate the `ChainSpec` prior to initialising the harness if you would like to use
@@ -104,7 +112,7 @@ static KZG_NO_PRECOMP: LazyLock<Arc<Kzg>> = LazyLock::new(|| {
 });
 
 pub fn get_kzg(spec: &ChainSpec) -> Arc<Kzg> {
-    if spec.eip7594_fork_epoch.is_some() {
+    if spec.fulu_fork_epoch.is_some() {
         KZG_PEERDAS.clone()
     } else if spec.deneb_fork_epoch.is_some() {
         KZG.clone()
@@ -116,7 +124,7 @@ pub fn get_kzg(spec: &ChainSpec) -> Arc<Kzg> {
 pub type BaseHarnessType<E, THotStore, TColdStore> =
     Witness<TestingSlotClock, CachingEth1Backend<E>, E, THotStore, TColdStore>;
 
-pub type DiskHarnessType<E> = BaseHarnessType<E, LevelDB<E>, LevelDB<E>>;
+pub type DiskHarnessType<E> = BaseHarnessType<E, BeaconNodeBackend<E>, BeaconNodeBackend<E>>;
 pub type EphemeralHarnessType<E> = BaseHarnessType<E, MemoryStore<E>, MemoryStore<E>>;
 
 pub type BoxedMutator<E, Hot, Cold> = Box<
@@ -223,6 +231,7 @@ pub struct Builder<T: BeaconChainTypes> {
     mock_execution_layer: Option<MockExecutionLayer<T::EthSpec>>,
     testing_slot_clock: Option<TestingSlotClock>,
     validator_monitor_config: Option<ValidatorMonitorConfig>,
+    import_all_data_columns: bool,
     runtime: TestRuntime,
     log: Logger,
 }
@@ -299,7 +308,10 @@ impl<E: EthSpec> Builder<EphemeralHarnessType<E>> {
 
 impl<E: EthSpec> Builder<DiskHarnessType<E>> {
     /// Disk store, start from genesis.
-    pub fn fresh_disk_store(mut self, store: Arc<HotColdDB<E, LevelDB<E>, LevelDB<E>>>) -> Self {
+    pub fn fresh_disk_store(
+        mut self,
+        store: Arc<HotColdDB<E, BeaconNodeBackend<E>, BeaconNodeBackend<E>>>,
+    ) -> Self {
         let validator_keypairs = self
             .validator_keypairs
             .clone()
@@ -324,7 +336,10 @@ impl<E: EthSpec> Builder<DiskHarnessType<E>> {
     }
 
     /// Disk store, resume.
-    pub fn resumed_disk_store(mut self, store: Arc<HotColdDB<E, LevelDB<E>, LevelDB<E>>>) -> Self {
+    pub fn resumed_disk_store(
+        mut self,
+        store: Arc<HotColdDB<E, BeaconNodeBackend<E>, BeaconNodeBackend<E>>>,
+    ) -> Self {
         let mutator = move |builder: BeaconChainBuilder<_>| {
             builder
                 .resume_from_db()
@@ -359,6 +374,7 @@ where
             mock_execution_layer: None,
             testing_slot_clock: None,
             validator_monitor_config: None,
+            import_all_data_columns: false,
             runtime,
             log,
         }
@@ -451,6 +467,11 @@ where
         self
     }
 
+    pub fn import_all_data_columns(mut self, import_all_data_columns: bool) -> Self {
+        self.import_all_data_columns = import_all_data_columns;
+        self
+    }
+
     pub fn execution_layer_from_url(mut self, url: &str) -> Self {
         assert!(
             self.execution_layer.is_none(),
@@ -501,6 +522,9 @@ where
             spec.electra_fork_epoch.map(|epoch| {
                 genesis_time + spec.seconds_per_slot * E::slots_per_epoch() * epoch.as_u64()
             });
+        mock.server.execution_block_generator().osaka_time = spec.fulu_fork_epoch.map(|epoch| {
+            genesis_time + spec.seconds_per_slot * E::slots_per_epoch() * epoch.as_u64()
+        });
 
         self
     }
@@ -511,7 +535,7 @@ where
 
     pub fn mock_execution_layer_with_config(mut self) -> Self {
         let mock = mock_execution_layer_from_parts::<E>(
-            self.spec.as_ref().expect("cannot build without spec"),
+            self.spec.clone().expect("cannot build without spec"),
             self.runtime.task_executor.clone(),
         );
         self.execution_layer = Some(mock.el.clone());
@@ -565,6 +589,7 @@ where
             .expect("should build dummy backend")
             .shutdown_sender(shutdown_tx)
             .chain_config(chain_config)
+            .import_all_data_columns(self.import_all_data_columns)
             .event_handler(Some(ServerSentEventHandler::new_with_capacity(
                 log.clone(),
                 5,
@@ -611,7 +636,7 @@ where
 }
 
 pub fn mock_execution_layer_from_parts<E: EthSpec>(
-    spec: &ChainSpec,
+    spec: Arc<ChainSpec>,
     task_executor: TaskExecutor,
 ) -> MockExecutionLayer<E> {
     let shanghai_time = spec.capella_fork_epoch.map(|epoch| {
@@ -623,8 +648,11 @@ pub fn mock_execution_layer_from_parts<E: EthSpec>(
     let prague_time = spec.electra_fork_epoch.map(|epoch| {
         HARNESS_GENESIS_TIME + spec.seconds_per_slot * E::slots_per_epoch() * epoch.as_u64()
     });
+    let osaka_time = spec.fulu_fork_epoch.map(|epoch| {
+        HARNESS_GENESIS_TIME + spec.seconds_per_slot * E::slots_per_epoch() * epoch.as_u64()
+    });
 
-    let kzg = get_kzg(spec);
+    let kzg = get_kzg(&spec);
 
     MockExecutionLayer::new(
         task_executor,
@@ -632,8 +660,9 @@ pub fn mock_execution_layer_from_parts<E: EthSpec>(
         shanghai_time,
         cancun_time,
         prague_time,
+        osaka_time,
         Some(JwtKey::from_slice(&DEFAULT_JWT_SECRET).unwrap()),
-        spec.clone(),
+        spec,
         Some(kzg),
     )
 }
@@ -662,10 +691,16 @@ pub struct BeaconChainHarness<T: BeaconChainTypes> {
     pub rng: Mutex<StdRng>,
 }
 
+pub type CommitteeSingleAttestations = Vec<(SingleAttestation, SubnetId)>;
 pub type CommitteeAttestations<E> = Vec<(Attestation<E>, SubnetId)>;
 pub type HarnessAttestations<E> =
     Vec<(CommitteeAttestations<E>, Option<SignedAggregateAndProof<E>>)>;
 
+pub type HarnessSingleAttestations<E> = Vec<(
+    CommitteeSingleAttestations,
+    Option<SignedAggregateAndProof<E>>,
+)>;
+
 pub type HarnessSyncContributions<E> = Vec<(
     Vec<(SyncCommitteeMessage, usize)>,
     Option<SignedContributionAndProof<E>>,
@@ -742,15 +777,13 @@ where
     pub fn get_head_block(&self) -> RpcBlock<E> {
         let block = self.chain.head_beacon_block();
         let block_root = block.canonical_root();
-        let blobs = self.chain.get_blobs(&block_root).unwrap();
-        RpcBlock::new(Some(block_root), block, Some(blobs)).unwrap()
+        self.build_rpc_block_from_store_blobs(Some(block_root), block)
     }
 
     pub fn get_full_block(&self, block_root: &Hash256) -> RpcBlock<E> {
         let block = self.chain.get_blinded_block(block_root).unwrap().unwrap();
         let full_block = self.chain.store.make_full_block(block_root, block).unwrap();
-        let blobs = self.chain.get_blobs(block_root).unwrap();
-        RpcBlock::new(Some(*block_root), Arc::new(full_block), Some(blobs)).unwrap()
+        self.build_rpc_block_from_store_blobs(Some(*block_root), Arc::new(full_block))
     }
 
     pub fn get_all_validators(&self) -> Vec<usize> {
@@ -913,15 +946,12 @@ where
             &self.spec,
         ));
 
-        let block_contents: SignedBlockContentsTuple<E> = match *signed_block {
-            SignedBeaconBlock::Base(_)
-            | SignedBeaconBlock::Altair(_)
-            | SignedBeaconBlock::Bellatrix(_)
-            | SignedBeaconBlock::Capella(_) => (signed_block, None),
-            SignedBeaconBlock::Deneb(_) | SignedBeaconBlock::Electra(_) => {
+        let block_contents: SignedBlockContentsTuple<E> =
+            if signed_block.fork_name_unchecked().deneb_enabled() {
                 (signed_block, block_response.blob_items)
-            }
-        };
+            } else {
+                (signed_block, None)
+            };
 
         (block_contents, block_response.state)
     }
@@ -977,15 +1007,12 @@ where
             &self.spec,
         ));
 
-        let block_contents: SignedBlockContentsTuple<E> = match *signed_block {
-            SignedBeaconBlock::Base(_)
-            | SignedBeaconBlock::Altair(_)
-            | SignedBeaconBlock::Bellatrix(_)
-            | SignedBeaconBlock::Capella(_) => (signed_block, None),
-            SignedBeaconBlock::Deneb(_) | SignedBeaconBlock::Electra(_) => {
+        let block_contents: SignedBlockContentsTuple<E> =
+            if signed_block.fork_name_unchecked().deneb_enabled() {
                 (signed_block, block_response.blob_items)
-            }
-        };
+            } else {
+                (signed_block, None)
+            };
         (block_contents, pre_state)
     }
 
@@ -1023,6 +1050,99 @@ where
         )
     }
 
+    #[allow(clippy::too_many_arguments)]
+    pub fn produce_single_attestation_for_block(
+        &self,
+        slot: Slot,
+        index: CommitteeIndex,
+        beacon_block_root: Hash256,
+        mut state: Cow<BeaconState<E>>,
+        state_root: Hash256,
+        aggregation_bit_index: usize,
+        validator_index: usize,
+    ) -> Result<SingleAttestation, BeaconChainError> {
+        let epoch = slot.epoch(E::slots_per_epoch());
+
+        if state.slot() > slot {
+            return Err(BeaconChainError::CannotAttestToFutureState);
+        } else if state.current_epoch() < epoch {
+            let mut_state = state.to_mut();
+            complete_state_advance(
+                mut_state,
+                Some(state_root),
+                epoch.start_slot(E::slots_per_epoch()),
+                &self.spec,
+            )?;
+            mut_state.build_committee_cache(RelativeEpoch::Current, &self.spec)?;
+        }
+
+        let committee_len = state.get_beacon_committee(slot, index)?.committee.len();
+
+        let target_slot = epoch.start_slot(E::slots_per_epoch());
+        let target_root = if state.slot() <= target_slot {
+            beacon_block_root
+        } else {
+            *state.get_block_root(target_slot)?
+        };
+
+        let attestation: Attestation<E> = Attestation::empty_for_signing(
+            index,
+            committee_len,
+            slot,
+            beacon_block_root,
+            state.current_justified_checkpoint(),
+            Checkpoint {
+                epoch,
+                root: target_root,
+            },
+            &self.spec,
+        )?;
+
+        let attestation = match attestation {
+            Attestation::Electra(mut attn) => {
+                attn.aggregation_bits
+                    .set(aggregation_bit_index, true)
+                    .unwrap();
+                attn
+            }
+            Attestation::Base(_) => panic!("Must be an Electra attestation"),
+        };
+
+        let aggregation_bits = attestation.get_aggregation_bits();
+
+        if aggregation_bits.len() != 1 {
+            panic!("Must be an unaggregated attestation")
+        }
+
+        let aggregation_bit = *aggregation_bits.first().unwrap();
+
+        let committee = state.get_beacon_committee(slot, index).unwrap();
+
+        let attester_index = committee
+            .committee
+            .iter()
+            .enumerate()
+            .find_map(|(i, &index)| {
+                if aggregation_bit as usize == i {
+                    return Some(index);
+                }
+                None
+            })
+            .unwrap();
+
+        let single_attestation =
+            attestation.to_single_attestation_with_attester_index(attester_index as u64)?;
+
+        let attestation: Attestation<E> = single_attestation.to_attestation(committee.committee)?;
+
+        assert_eq!(
+            single_attestation.committee_index,
+            attestation.committee_index().unwrap()
+        );
+        assert_eq!(single_attestation.attester_index, validator_index as u64);
+        Ok(single_attestation)
+    }
+
     /// Produces an "unaggregated" attestation for the given `slot` and `index` that attests to
     /// `beacon_block_root`. The provided `state` should match the `block.state_root` for the
     /// `block` identified by `beacon_block_root`.
@@ -1080,6 +1200,33 @@ where
         )?)
     }
 
+    /// A list of attestations for each committee for the given slot.
+    ///
+    /// The first layer of the Vec is organised per committee. For example, if the return value is
+    /// called `all_attestations`, then all attestations in `all_attestations[0]` will be for
+    /// committee 0, whilst all in `all_attestations[1]` will be for committee 1.
+    pub fn make_single_attestations(
+        &self,
+        attesting_validators: &[usize],
+        state: &BeaconState<E>,
+        state_root: Hash256,
+        head_block_root: SignedBeaconBlockHash,
+        attestation_slot: Slot,
+    ) -> Vec<CommitteeSingleAttestations> {
+        let fork = self
+            .spec
+            .fork_at_epoch(attestation_slot.epoch(E::slots_per_epoch()));
+        self.make_single_attestations_with_opts(
+            attesting_validators,
+            state,
+            state_root,
+            head_block_root,
+            attestation_slot,
+            MakeAttestationOptions { limit: None, fork },
+        )
+        .0
+    }
+
     /// A list of attestations for each committee for the given slot.
     ///
     /// The first layer of the Vec is organised per committee. For example, if the return value is
@@ -1107,6 +1254,99 @@ where
         .0
     }
 
+    pub fn make_single_attestations_with_opts(
+        &self,
+        attesting_validators: &[usize],
+        state: &BeaconState<E>,
+        state_root: Hash256,
+        head_block_root: SignedBeaconBlockHash,
+        attestation_slot: Slot,
+        opts: MakeAttestationOptions,
+    ) -> (Vec<CommitteeSingleAttestations>, Vec<usize>) {
+        let MakeAttestationOptions { limit, fork } = opts;
+        let committee_count = state.get_committee_count_at_slot(state.slot()).unwrap();
+        let num_attesters = AtomicUsize::new(0);
+
+        let (attestations, split_attesters) = state
+            .get_beacon_committees_at_slot(attestation_slot)
+            .expect("should get committees")
+            .iter()
+            .map(|bc| {
+                bc.committee
+                    .par_iter()
+                    .enumerate()
+                    .filter_map(|(i, validator_index)| {
+                        if !attesting_validators.contains(validator_index) {
+                            return None;
+                        }
+
+                        if let Some(limit) = limit {
+                            // This atomics stuff is necessary because we're under a par_iter,
+                            // and Rayon will deadlock if we use a mutex.
+                            if num_attesters.fetch_add(1, Ordering::Relaxed) >= limit {
+                                num_attesters.fetch_sub(1, Ordering::Relaxed);
+                                return None;
+                            }
+                        }
+
+                        let mut attestation = self
+                            .produce_single_attestation_for_block(
+                                attestation_slot,
+                                bc.index,
+                                head_block_root.into(),
+                                Cow::Borrowed(state),
+                                state_root,
+                                i,
+                                *validator_index,
+                            )
+                            .unwrap();
+
+                        attestation.signature = {
+                            let domain = self.spec.get_domain(
+                                attestation.data.target.epoch,
+                                Domain::BeaconAttester,
+                                &fork,
+                                state.genesis_validators_root(),
+                            );
+
+                            let message = attestation.data.signing_root(domain);
+
+                            let mut agg_sig = AggregateSignature::infinity();
+
+                            agg_sig.add_assign(
+                                &self.validator_keypairs[*validator_index].sk.sign(message),
+                            );
+
+                            agg_sig
+                        };
+
+                        let subnet_id = SubnetId::compute_subnet_for_single_attestation::<E>(
+                            &attestation,
+                            committee_count,
+                            &self.chain.spec,
+                        )
+                        .unwrap();
+
+                        Some(((attestation, subnet_id), validator_index))
+                    })
+                    .unzip::<_, _, Vec<_>, Vec<_>>()
+            })
+            .unzip::<_, _, Vec<_>, Vec<_>>();
+
+        // Flatten attesters.
+        let attesters = split_attesters.into_iter().flatten().collect::<Vec<_>>();
+
+        if let Some(limit) = limit {
+            assert_eq!(limit, num_attesters.load(Ordering::Relaxed));
+            assert_eq!(
+                limit,
+                attesters.len(),
+                "failed to generate `limit` attestations"
+            );
+        }
+        (attestations, attesters)
+    }
+
     pub fn make_unaggregated_attestations_with_opts(
         &self,
         attesting_validators: &[usize],
@@ -1287,6 +1527,32 @@ where
         )
     }
 
+    /// A list of attestations for each committee for the given slot.
+    ///
+    /// The first layer of the Vec is organised per committee. For example, if the return value is
+    /// called `all_attestations`, then all attestations in `all_attestations[0]` will be for
+    /// committee 0, whilst all in `all_attestations[1]` will be for committee 1.
+    pub fn get_single_attestations(
+        &self,
+        attestation_strategy: &AttestationStrategy,
+        state: &BeaconState<E>,
+        state_root: Hash256,
+        head_block_root: Hash256,
+        attestation_slot: Slot,
+    ) -> Vec<Vec<(SingleAttestation, SubnetId)>> {
+        let validators: Vec<usize> = match attestation_strategy {
+            AttestationStrategy::AllValidators => self.get_all_validators(),
+            AttestationStrategy::SomeValidators(vals) => vals.clone(),
+        };
+        self.make_single_attestations(
+            &validators,
+            state,
+            state_root,
+            head_block_root.into(),
+            attestation_slot,
+        )
+    }
+
     pub fn make_attestations(
         &self,
         attesting_validators: &[usize],
@@ -2018,22 +2284,19 @@ where
         self.set_current_slot(slot);
         let (block, blob_items) = block_contents;
 
-        let sidecars = blob_items
-            .map(|(proofs, blobs)| BlobSidecar::build_sidecars(blobs, &block, proofs))
-            .transpose()
-            .unwrap();
+        let rpc_block = self.build_rpc_block_from_blobs(block_root, block, blob_items)?;
         let block_hash: SignedBeaconBlockHash = self
             .chain
             .process_block(
                 block_root,
-                RpcBlock::new(Some(block_root), block, sidecars).unwrap(),
+                rpc_block,
                 NotifyExecutionLayer::Yes,
                 BlockImportSource::RangeSync,
                 || Ok(()),
             )
             .await?
             .try_into()
-            .unwrap();
+            .expect("block blobs are available");
         self.chain.recompute_head_at_current_slot().await;
         Ok(block_hash)
     }
@@ -2044,16 +2307,13 @@ where
     ) -> Result<SignedBeaconBlockHash, BlockError> {
         let (block, blob_items) = block_contents;
 
-        let sidecars = blob_items
-            .map(|(proofs, blobs)| BlobSidecar::build_sidecars(blobs, &block, proofs))
-            .transpose()
-            .unwrap();
         let block_root = block.canonical_root();
+        let rpc_block = self.build_rpc_block_from_blobs(block_root, block, blob_items)?;
         let block_hash: SignedBeaconBlockHash = self
             .chain
             .process_block(
                 block_root,
-                RpcBlock::new(Some(block_root), block, sidecars).unwrap(),
+                rpc_block,
                 NotifyExecutionLayer::Yes,
                 BlockImportSource::RangeSync,
                 || Ok(()),
@@ -2065,6 +2325,75 @@ where
         Ok(block_hash)
     }
 
+    /// Builds an `Rpc` block from a `SignedBeaconBlock` and blobs or data columns retrieved from
+    /// the database.
+    pub fn build_rpc_block_from_store_blobs(
+        &self,
+        block_root: Option<Hash256>,
+        block: Arc<SignedBeaconBlock<E>>,
+    ) -> RpcBlock<E> {
+        let block_root = block_root.unwrap_or_else(|| get_block_root(&block));
+        let has_blobs = block
+            .message()
+            .body()
+            .blob_kzg_commitments()
+            .is_ok_and(|c| !c.is_empty());
+        if !has_blobs {
+            return RpcBlock::new_without_blobs(Some(block_root), block);
+        }
+
+        // Blobs are stored as data columns from Fulu (PeerDAS)
+        if self.spec.is_peer_das_enabled_for_epoch(block.epoch()) {
+            let columns = self.chain.get_data_columns(&block_root).unwrap().unwrap();
+            let custody_columns = columns
+                .into_iter()
+                .map(CustodyDataColumn::from_asserted_custody)
+                .collect::<Vec<_>>();
+            RpcBlock::new_with_custody_columns(Some(block_root), block, custody_columns, &self.spec)
+                .unwrap()
+        } else {
+            let blobs = self.chain.get_blobs(&block_root).unwrap().blobs();
+            RpcBlock::new(Some(block_root), block, blobs).unwrap()
+        }
+    }
+
+    /// Builds an `RpcBlock` from a `SignedBeaconBlock` and `BlobsList`.
+    fn build_rpc_block_from_blobs(
+        &self,
+        block_root: Hash256,
+        block: Arc<SignedBeaconBlock<E, FullPayload<E>>>,
+        blob_items: Option<(KzgProofs<E>, BlobsList<E>)>,
+    ) -> Result<RpcBlock<E>, BlockError> {
+        Ok(if self.spec.is_peer_das_enabled_for_epoch(block.epoch()) {
+            let sampling_column_count = self
+                .chain
+                .data_availability_checker
+                .get_sampling_column_count();
+
+            if blob_items.is_some_and(|(_, blobs)| !blobs.is_empty()) {
+                // Note: this method ignores the actual custody columns and just take the first
+                // `sampling_column_count` for testing purpose only, because the chain does not
+                // currently have any knowledge of the columns being custodied.
+                let columns = generate_data_column_sidecars_from_block(&block, &self.spec)
+                    .into_iter()
+                    .take(sampling_column_count)
+                    .map(CustodyDataColumn::from_asserted_custody)
+                    .collect::<Vec<_>>();
+                RpcBlock::new_with_custody_columns(Some(block_root), block, columns, &self.spec)?
+            } else {
+                RpcBlock::new_without_blobs(Some(block_root), block)
+            }
+        } else {
+            let blobs = blob_items
+                .map(|(proofs, blobs)| {
+                    BlobSidecar::build_sidecars(blobs, &block, proofs, &self.spec)
+                })
+                .transpose()
+                .unwrap();
+            RpcBlock::new(Some(block_root), block, blobs)?
+        })
+    }
+
     pub fn process_attestations(&self, attestations: HarnessAttestations<E>) {
         let num_validators = self.validator_keypairs.len();
         let mut unaggregated = Vec::with_capacity(num_validators);
@@ -2738,6 +3067,56 @@ where
 
         Ok(())
     }
+
+    /// Simulate some of the blobs / data columns being seen on gossip.
+    /// Converts the blobs to data columns if the slot is Fulu or later.
+    pub async fn process_gossip_blobs_or_columns<'a>(
+        &self,
+        block: &SignedBeaconBlock<E>,
+        blobs: impl Iterator<Item = &'a Blob<E>>,
+        proofs: impl Iterator<Item = &'a KzgProof>,
+        custody_columns_opt: Option<HashSet<ColumnIndex>>,
+    ) {
+        let is_peerdas_enabled = self.chain.spec.is_peer_das_enabled_for_epoch(block.epoch());
+        if is_peerdas_enabled {
+            let custody_columns = custody_columns_opt.unwrap_or_else(|| {
+                let sampling_column_count = self
+                    .chain
+                    .data_availability_checker
+                    .get_sampling_column_count() as u64;
+                (0..sampling_column_count).collect()
+            });
+
+            let verified_columns = generate_data_column_sidecars_from_block(block, &self.spec)
+                .into_iter()
+                .filter(|c| custody_columns.contains(&c.index))
+                .map(|sidecar| {
+                    let column_index = sidecar.index;
+                    self.chain
+                        .verify_data_column_sidecar_for_gossip(sidecar, column_index)
+                })
+                .collect::<Result<Vec<_>, _>>()
+                .unwrap();
+
+            if !verified_columns.is_empty() {
+                self.chain
+                    .process_gossip_data_columns(verified_columns, || Ok(()))
+                    .await
+                    .unwrap();
+            }
+        } else {
+            for (i, (kzg_proof, blob)) in proofs.into_iter().zip(blobs).enumerate() {
+                let sidecar =
+                    Arc::new(BlobSidecar::new(i, blob.clone(), block, *kzg_proof).unwrap());
+                let gossip_blob = GossipVerifiedBlob::new(sidecar, i as u64, &self.chain)
+                    .expect("should obtain gossip verified blob");
+                self.chain
+                    .process_gossip_blob(gossip_blob)
+                    .await
+                    .expect("should import valid gossip verified blob");
+            }
+        }
+    }
 }
 
 // Junk `Debug` impl to satistfy certain trait bounds during testing.
@@ -2816,11 +3195,12 @@ pub fn generate_rand_block_and_blobs<E: EthSpec>(
     fork_name: ForkName,
     num_blobs: NumBlobs,
     rng: &mut impl Rng,
+    spec: &ChainSpec,
 ) -> (SignedBeaconBlock<E, FullPayload<E>>, Vec<BlobSidecar<E>>) {
     let inner = map_fork_name!(fork_name, BeaconBlock, <_>::random_for_test(rng));
 
     let mut block = SignedBeaconBlock::from_block(inner, types::Signature::random_for_test(rng));
-
+    let max_blobs = spec.max_blobs_per_block(block.epoch()) as usize;
     let mut blob_sidecars = vec![];
 
     let bundle = match block {
@@ -2830,7 +3210,7 @@ pub fn generate_rand_block_and_blobs<E: EthSpec>(
             // Get either zero blobs or a random number of blobs between 1 and Max Blobs.
             let payload: &mut FullPayloadDeneb<E> = &mut message.body.execution_payload;
             let num_blobs = match num_blobs {
-                NumBlobs::Random => rng.gen_range(1..=E::max_blobs_per_block()),
+                NumBlobs::Random => rng.gen_range(1..=max_blobs),
                 NumBlobs::Number(n) => n,
                 NumBlobs::None => 0,
             };
@@ -2850,7 +3230,26 @@ pub fn generate_rand_block_and_blobs<E: EthSpec>(
             // Get either zero blobs or a random number of blobs between 1 and Max Blobs.
             let payload: &mut FullPayloadElectra<E> = &mut message.body.execution_payload;
             let num_blobs = match num_blobs {
-                NumBlobs::Random => rng.gen_range(1..=E::max_blobs_per_block()),
+                NumBlobs::Random => rng.gen_range(1..=max_blobs),
+                NumBlobs::Number(n) => n,
+                NumBlobs::None => 0,
+            };
+            let (bundle, transactions) =
+                execution_layer::test_utils::generate_blobs::<E>(num_blobs).unwrap();
+            payload.execution_payload.transactions = <_>::default();
+            for tx in Vec::from(transactions) {
+                payload.execution_payload.transactions.push(tx).unwrap();
+            }
+            message.body.blob_kzg_commitments = bundle.commitments.clone();
+            bundle
+        }
+        SignedBeaconBlock::Fulu(SignedBeaconBlockFulu {
+            ref mut message, ..
+        }) => {
+            // Get either zero blobs or a random number of blobs between 1 and Max Blobs.
+            let payload: &mut FullPayloadFulu<E> = &mut message.body.execution_payload;
+            let num_blobs = match num_blobs {
+                NumBlobs::Random => rng.gen_range(1..=max_blobs),
                 NumBlobs::Number(n) => n,
                 NumBlobs::None => 0,
             };
@@ -2903,10 +3302,59 @@ pub fn generate_rand_block_and_data_columns<E: EthSpec>(
     SignedBeaconBlock<E, FullPayload<E>>,
     DataColumnSidecarList<E>,
 ) {
-    let kzg = get_kzg(spec);
-    let (block, blobs) = generate_rand_block_and_blobs(fork_name, num_blobs, rng);
-    let blob_refs = blobs.iter().map(|b| &b.blob).collect::<Vec<_>>();
-    let data_columns = blobs_to_data_column_sidecars(&blob_refs, &block, &kzg, spec).unwrap();
-
+    let (block, _blobs) = generate_rand_block_and_blobs(fork_name, num_blobs, rng, spec);
+    let data_columns = generate_data_column_sidecars_from_block(&block, spec);
     (block, data_columns)
 }
+
+/// Generate data column sidecars from pre-computed cells and proofs.
+fn generate_data_column_sidecars_from_block<E: EthSpec>(
+    block: &SignedBeaconBlock<E>,
+    spec: &ChainSpec,
+) -> DataColumnSidecarList<E> {
+    let kzg_commitments = block.message().body().blob_kzg_commitments().unwrap();
+    if kzg_commitments.is_empty() {
+        return vec![];
+    }
+
+    let kzg_commitments_inclusion_proof = block
+        .message()
+        .body()
+        .kzg_commitments_merkle_proof()
+        .unwrap();
+    let signed_block_header = block.signed_block_header();
+
+    // load the precomputed column sidecar to avoid computing them for every block in the tests.
+    let template_data_columns = RuntimeVariableList::<DataColumnSidecar<E>>::from_ssz_bytes(
+        TEST_DATA_COLUMN_SIDECARS_SSZ,
+        spec.number_of_columns as usize,
+    )
+    .unwrap();
+
+    let (cells, proofs) = template_data_columns
+        .into_iter()
+        .map(|sidecar| {
+            let DataColumnSidecar {
+                column, kzg_proofs, ..
+            } = sidecar;
+            // There's only one cell per column for a single blob
+            let cell_bytes: Vec<u8> = column.into_iter().next().unwrap().into();
+            let kzg_cell = cell_bytes.try_into().unwrap();
+            let kzg_proof = kzg_proofs.into_iter().next().unwrap();
+            (kzg_cell, kzg_proof)
+        })
+        .collect::<(Vec<_>, Vec<_>)>();
+
+    // Repeat the cells and proofs for every blob
+    let blob_cells_and_proofs_vec =
+        vec![(cells.try_into().unwrap(), proofs.try_into().unwrap()); kzg_commitments.len()];
+
+    build_data_column_sidecars(
+        kzg_commitments.clone(),
+        kzg_commitments_inclusion_proof,
+        signed_block_header,
+        blob_cells_and_proofs_vec,
+        spec,
+    )
+    .unwrap()
+}
diff --git a/beacon_node/beacon_chain/src/test_utils/fixtures/test_data_column_sidecars.ssz b/beacon_node/beacon_chain/src/test_utils/fixtures/test_data_column_sidecars.ssz
new file mode 100644
index 0000000000..112dd43b04
Binary files /dev/null and b/beacon_node/beacon_chain/src/test_utils/fixtures/test_data_column_sidecars.ssz differ
diff --git a/beacon_node/beacon_chain/tests/attestation_production.rs b/beacon_node/beacon_chain/tests/attestation_production.rs
index 87fefe7114..621475a3ec 100644
--- a/beacon_node/beacon_chain/tests/attestation_production.rs
+++ b/beacon_node/beacon_chain/tests/attestation_production.rs
@@ -1,7 +1,6 @@
 #![cfg(not(debug_assertions))]
 
 use beacon_chain::attestation_simulator::produce_unaggregated_attestation;
-use beacon_chain::block_verification_types::RpcBlock;
 use beacon_chain::test_utils::{AttestationStrategy, BeaconChainHarness, BlockStrategy};
 use beacon_chain::validator_monitor::UNAGGREGATED_ATTESTATION_LAG_SLOTS;
 use beacon_chain::{metrics, StateSkipConfig, WhenSlotSkipped};
@@ -155,7 +154,6 @@ async fn produces_attestations() {
             .store
             .make_full_block(&block_root, blinded_block)
             .unwrap();
-        let blobs = chain.get_blobs(&block_root).unwrap();
 
         let epoch_boundary_slot = state
             .current_epoch()
@@ -223,8 +221,7 @@ async fn produces_attestations() {
             assert_eq!(data.target.root, target_root, "bad target root");
 
             let rpc_block =
-                RpcBlock::<MainnetEthSpec>::new(None, Arc::new(block.clone()), Some(blobs.clone()))
-                    .unwrap();
+                harness.build_rpc_block_from_store_blobs(Some(block_root), Arc::new(block.clone()));
             let beacon_chain::data_availability_checker::MaybeAvailableBlock::Available(
                 available_block,
             ) = chain
@@ -296,13 +293,8 @@ async fn early_attester_cache_old_request() {
         .get_block(&head.beacon_block_root)
         .unwrap();
 
-    let head_blobs = harness
-        .chain
-        .get_blobs(&head.beacon_block_root)
-        .expect("should get blobs");
-
-    let rpc_block =
-        RpcBlock::<MainnetEthSpec>::new(None, head.beacon_block.clone(), Some(head_blobs)).unwrap();
+    let rpc_block = harness
+        .build_rpc_block_from_store_blobs(Some(head.beacon_block_root), head.beacon_block.clone());
     let beacon_chain::data_availability_checker::MaybeAvailableBlock::Available(available_block) =
         harness
             .chain
diff --git a/beacon_node/beacon_chain/tests/block_verification.rs b/beacon_node/beacon_chain/tests/block_verification.rs
index f094a173ee..2a881b5b0f 100644
--- a/beacon_node/beacon_chain/tests/block_verification.rs
+++ b/beacon_node/beacon_chain/tests/block_verification.rs
@@ -1,6 +1,7 @@
 #![cfg(not(debug_assertions))]
 
 use beacon_chain::block_verification_types::{AsBlock, ExecutedBlock, RpcBlock};
+use beacon_chain::data_column_verification::CustodyDataColumn;
 use beacon_chain::{
     test_utils::{
         test_spec, AttestationStrategy, BeaconChainHarness, BlockStrategy, EphemeralHarnessType,
@@ -9,7 +10,7 @@ use beacon_chain::{
 };
 use beacon_chain::{
     BeaconSnapshot, BlockError, ChainConfig, ChainSegmentResult, IntoExecutionPendingBlock,
-    NotifyExecutionLayer,
+    InvalidSignature, NotifyExecutionLayer,
 };
 use logging::test_logger;
 use slasher::{Config as SlasherConfig, Slasher};
@@ -34,7 +35,12 @@ const BLOCK_INDICES: &[usize] = &[0, 1, 32, 64, 68 + 1, 129, CHAIN_SEGMENT_LENGT
 static KEYPAIRS: LazyLock<Vec<Keypair>> =
     LazyLock::new(|| types::test_utils::generate_deterministic_keypairs(VALIDATOR_COUNT));
 
-async fn get_chain_segment() -> (Vec<BeaconSnapshot<E>>, Vec<Option<BlobSidecarList<E>>>) {
+enum DataSidecars<E: EthSpec> {
+    Blobs(BlobSidecarList<E>),
+    DataColumns(Vec<CustodyDataColumn<E>>),
+}
+
+async fn get_chain_segment() -> (Vec<BeaconSnapshot<E>>, Vec<Option<DataSidecars<E>>>) {
     let harness = get_harness(VALIDATOR_COUNT);
 
     harness
@@ -46,7 +52,7 @@ async fn get_chain_segment() -> (Vec<BeaconSnapshot<E>>, Vec<Option<BlobSidecarL
         .await;
 
     let mut segment = Vec::with_capacity(CHAIN_SEGMENT_LENGTH);
-    let mut segment_blobs = Vec::with_capacity(CHAIN_SEGMENT_LENGTH);
+    let mut segment_sidecars = Vec::with_capacity(CHAIN_SEGMENT_LENGTH);
     for snapshot in harness
         .chain
         .chain_dump()
@@ -60,60 +66,38 @@ async fn get_chain_segment() -> (Vec<BeaconSnapshot<E>>, Vec<Option<BlobSidecarL
             .await
             .unwrap()
             .unwrap();
+        let block_epoch = full_block.epoch();
+
         segment.push(BeaconSnapshot {
             beacon_block_root: snapshot.beacon_block_root,
             beacon_block: Arc::new(full_block),
             beacon_state: snapshot.beacon_state,
         });
-        segment_blobs.push(Some(
+
+        let data_sidecars = if harness.spec.is_peer_das_enabled_for_epoch(block_epoch) {
+            harness
+                .chain
+                .get_data_columns(&snapshot.beacon_block_root)
+                .unwrap()
+                .map(|columns| {
+                    columns
+                        .into_iter()
+                        .map(CustodyDataColumn::from_asserted_custody)
+                        .collect()
+                })
+                .map(DataSidecars::DataColumns)
+        } else {
             harness
                 .chain
                 .get_blobs(&snapshot.beacon_block_root)
-                .unwrap(),
-        ))
+                .unwrap()
+                .blobs()
+                .map(DataSidecars::Blobs)
+        };
+
+        segment_sidecars.push(data_sidecars);
     }
-    (segment, segment_blobs)
-}
-
-async fn get_chain_segment_with_blob_sidecars(
-) -> (Vec<BeaconSnapshot<E>>, Vec<Option<BlobSidecarList<E>>>) {
-    let harness = get_harness(VALIDATOR_COUNT);
-
-    harness
-        .extend_chain(
-            CHAIN_SEGMENT_LENGTH,
-            BlockStrategy::OnCanonicalHead,
-            AttestationStrategy::AllValidators,
-        )
-        .await;
-
-    let mut segment = Vec::with_capacity(CHAIN_SEGMENT_LENGTH);
-    let mut segment_blobs = Vec::with_capacity(CHAIN_SEGMENT_LENGTH);
-    for snapshot in harness
-        .chain
-        .chain_dump()
-        .expect("should dump chain")
-        .into_iter()
-        .skip(1)
-    {
-        let full_block = harness
-            .chain
-            .get_block(&snapshot.beacon_block_root)
-            .await
-            .unwrap()
-            .unwrap();
-        segment.push(BeaconSnapshot {
-            beacon_block_root: snapshot.beacon_block_root,
-            beacon_block: Arc::new(full_block),
-            beacon_state: snapshot.beacon_state,
-        });
-        let blob_sidecars = harness
-            .chain
-            .get_blobs(&snapshot.beacon_block_root)
-            .unwrap();
-        segment_blobs.push(Some(blob_sidecars))
-    }
-    (segment, segment_blobs)
+    (segment, segment_sidecars)
 }
 
 fn get_harness(validator_count: usize) -> BeaconChainHarness<EphemeralHarnessType<E>> {
@@ -135,17 +119,35 @@ fn get_harness(validator_count: usize) -> BeaconChainHarness<EphemeralHarnessTyp
 
 fn chain_segment_blocks(
     chain_segment: &[BeaconSnapshot<E>],
-    blobs: &[Option<BlobSidecarList<E>>],
+    chain_segment_sidecars: &[Option<DataSidecars<E>>],
+    spec: &ChainSpec,
 ) -> Vec<RpcBlock<E>> {
     chain_segment
         .iter()
-        .zip(blobs.iter())
-        .map(|(snapshot, blobs)| {
-            RpcBlock::new(None, snapshot.beacon_block.clone(), blobs.clone()).unwrap()
+        .zip(chain_segment_sidecars.iter())
+        .map(|(snapshot, data_sidecars)| {
+            let block = snapshot.beacon_block.clone();
+            build_rpc_block(block, data_sidecars, spec)
         })
         .collect()
 }
 
+fn build_rpc_block(
+    block: Arc<SignedBeaconBlock<E>>,
+    data_sidecars: &Option<DataSidecars<E>>,
+    spec: &ChainSpec,
+) -> RpcBlock<E> {
+    match data_sidecars {
+        Some(DataSidecars::Blobs(blobs)) => {
+            RpcBlock::new(None, block, Some(blobs.clone())).unwrap()
+        }
+        Some(DataSidecars::DataColumns(columns)) => {
+            RpcBlock::new_with_custody_columns(None, block, columns.clone(), spec).unwrap()
+        }
+        None => RpcBlock::new_without_blobs(None, block),
+    }
+}
+
 fn junk_signature() -> Signature {
     let kp = generate_deterministic_keypair(VALIDATOR_COUNT);
     let message = Hash256::from_slice(&[42; 32]);
@@ -184,18 +186,22 @@ fn update_proposal_signatures(
     }
 }
 
-fn update_parent_roots(
-    snapshots: &mut [BeaconSnapshot<E>],
-    blobs: &mut [Option<BlobSidecarList<E>>],
-) {
+fn update_parent_roots(snapshots: &mut [BeaconSnapshot<E>], blobs: &mut [Option<DataSidecars<E>>]) {
     for i in 0..snapshots.len() {
         let root = snapshots[i].beacon_block.canonical_root();
         if let (Some(child), Some(child_blobs)) = (snapshots.get_mut(i + 1), blobs.get_mut(i + 1)) {
             let (mut block, signature) = child.beacon_block.as_ref().clone().deconstruct();
             *block.parent_root_mut() = root;
             let new_child = Arc::new(SignedBeaconBlock::from_block(block, signature));
-            if let Some(blobs) = child_blobs {
-                update_blob_signed_header(&new_child, blobs);
+            if let Some(data_sidecars) = child_blobs {
+                match data_sidecars {
+                    DataSidecars::Blobs(blobs) => {
+                        update_blob_signed_header(&new_child, blobs);
+                    }
+                    DataSidecars::DataColumns(columns) => {
+                        update_data_column_signed_header(&new_child, columns);
+                    }
+                }
             }
             child.beacon_block = new_child;
         }
@@ -206,7 +212,7 @@ fn update_blob_signed_header<E: EthSpec>(
     signed_block: &SignedBeaconBlock<E>,
     blobs: &mut BlobSidecarList<E>,
 ) {
-    for old_blob_sidecar in blobs.iter_mut() {
+    for old_blob_sidecar in blobs.as_mut_slice() {
         let new_blob = Arc::new(BlobSidecar::<E> {
             index: old_blob_sidecar.index,
             blob: old_blob_sidecar.blob.clone(),
@@ -223,13 +229,36 @@ fn update_blob_signed_header<E: EthSpec>(
     }
 }
 
+fn update_data_column_signed_header<E: EthSpec>(
+    signed_block: &SignedBeaconBlock<E>,
+    data_columns: &mut Vec<CustodyDataColumn<E>>,
+) {
+    for old_custody_column_sidecar in data_columns.as_mut_slice() {
+        let old_column_sidecar = old_custody_column_sidecar.as_data_column();
+        let new_column_sidecar = Arc::new(DataColumnSidecar::<E> {
+            index: old_column_sidecar.index,
+            column: old_column_sidecar.column.clone(),
+            kzg_commitments: old_column_sidecar.kzg_commitments.clone(),
+            kzg_proofs: old_column_sidecar.kzg_proofs.clone(),
+            signed_block_header: signed_block.signed_block_header(),
+            kzg_commitments_inclusion_proof: signed_block
+                .message()
+                .body()
+                .kzg_commitments_merkle_proof()
+                .unwrap(),
+        });
+        *old_custody_column_sidecar = CustodyDataColumn::from_asserted_custody(new_column_sidecar);
+    }
+}
+
 #[tokio::test]
 async fn chain_segment_full_segment() {
     let harness = get_harness(VALIDATOR_COUNT);
     let (chain_segment, chain_segment_blobs) = get_chain_segment().await;
-    let blocks: Vec<RpcBlock<E>> = chain_segment_blocks(&chain_segment, &chain_segment_blobs)
-        .into_iter()
-        .collect();
+    let blocks: Vec<RpcBlock<E>> =
+        chain_segment_blocks(&chain_segment, &chain_segment_blobs, &harness.spec)
+            .into_iter()
+            .collect();
 
     harness
         .chain
@@ -265,9 +294,10 @@ async fn chain_segment_varying_chunk_size() {
     for chunk_size in &[1, 2, 3, 5, 31, 32, 33, 42] {
         let harness = get_harness(VALIDATOR_COUNT);
         let (chain_segment, chain_segment_blobs) = get_chain_segment().await;
-        let blocks: Vec<RpcBlock<E>> = chain_segment_blocks(&chain_segment, &chain_segment_blobs)
-            .into_iter()
-            .collect();
+        let blocks: Vec<RpcBlock<E>> =
+            chain_segment_blocks(&chain_segment, &chain_segment_blobs, &harness.spec)
+                .into_iter()
+                .collect();
 
         harness
             .chain
@@ -306,9 +336,10 @@ async fn chain_segment_non_linear_parent_roots() {
     /*
      * Test with a block removed.
      */
-    let mut blocks: Vec<RpcBlock<E>> = chain_segment_blocks(&chain_segment, &chain_segment_blobs)
-        .into_iter()
-        .collect();
+    let mut blocks: Vec<RpcBlock<E>> =
+        chain_segment_blocks(&chain_segment, &chain_segment_blobs, &harness.spec)
+            .into_iter()
+            .collect();
     blocks.remove(2);
 
     assert!(
@@ -326,9 +357,10 @@ async fn chain_segment_non_linear_parent_roots() {
     /*
      * Test with a modified parent root.
      */
-    let mut blocks: Vec<RpcBlock<E>> = chain_segment_blocks(&chain_segment, &chain_segment_blobs)
-        .into_iter()
-        .collect();
+    let mut blocks: Vec<RpcBlock<E>> =
+        chain_segment_blocks(&chain_segment, &chain_segment_blobs, &harness.spec)
+            .into_iter()
+            .collect();
 
     let (mut block, signature) = blocks[3].as_block().clone().deconstruct();
     *block.parent_root_mut() = Hash256::zero();
@@ -363,9 +395,10 @@ async fn chain_segment_non_linear_slots() {
      * Test where a child is lower than the parent.
      */
 
-    let mut blocks: Vec<RpcBlock<E>> = chain_segment_blocks(&chain_segment, &chain_segment_blobs)
-        .into_iter()
-        .collect();
+    let mut blocks: Vec<RpcBlock<E>> =
+        chain_segment_blocks(&chain_segment, &chain_segment_blobs, &harness.spec)
+            .into_iter()
+            .collect();
     let (mut block, signature) = blocks[3].as_block().clone().deconstruct();
     *block.slot_mut() = Slot::new(0);
     blocks[3] = RpcBlock::new_without_blobs(
@@ -389,9 +422,10 @@ async fn chain_segment_non_linear_slots() {
      * Test where a child is equal to the parent.
      */
 
-    let mut blocks: Vec<RpcBlock<E>> = chain_segment_blocks(&chain_segment, &chain_segment_blobs)
-        .into_iter()
-        .collect();
+    let mut blocks: Vec<RpcBlock<E>> =
+        chain_segment_blocks(&chain_segment, &chain_segment_blobs, &harness.spec)
+            .into_iter()
+            .collect();
     let (mut block, signature) = blocks[3].as_block().clone().deconstruct();
     *block.slot_mut() = blocks[2].slot();
     blocks[3] = RpcBlock::new_without_blobs(
@@ -414,7 +448,7 @@ async fn chain_segment_non_linear_slots() {
 
 async fn assert_invalid_signature(
     chain_segment: &[BeaconSnapshot<E>],
-    chain_segment_blobs: &[Option<BlobSidecarList<E>>],
+    chain_segment_blobs: &[Option<DataSidecars<E>>],
     harness: &BeaconChainHarness<EphemeralHarnessType<E>>,
     block_index: usize,
     snapshots: &[BeaconSnapshot<E>],
@@ -424,7 +458,7 @@ async fn assert_invalid_signature(
         .iter()
         .zip(chain_segment_blobs.iter())
         .map(|(snapshot, blobs)| {
-            RpcBlock::new(None, snapshot.beacon_block.clone(), blobs.clone()).unwrap()
+            build_rpc_block(snapshot.beacon_block.clone(), blobs, &harness.spec)
         })
         .collect();
 
@@ -436,7 +470,7 @@ async fn assert_invalid_signature(
                 .process_chain_segment(blocks, NotifyExecutionLayer::Yes)
                 .await
                 .into_block_error(),
-            Err(BlockError::InvalidSignature)
+            Err(BlockError::InvalidSignature(InvalidSignature::Unknown))
         ),
         "should not import chain segment with an invalid {} signature",
         item
@@ -451,7 +485,7 @@ async fn assert_invalid_signature(
         .take(block_index)
         .zip(chain_segment_blobs.iter())
         .map(|(snapshot, blobs)| {
-            RpcBlock::new(None, snapshot.beacon_block.clone(), blobs.clone()).unwrap()
+            build_rpc_block(snapshot.beacon_block.clone(), blobs, &harness.spec)
         })
         .collect();
     // We don't care if this fails, we just call this to ensure that all prior blocks have been
@@ -466,19 +500,23 @@ async fn assert_invalid_signature(
         .chain
         .process_block(
             snapshots[block_index].beacon_block.canonical_root(),
-            RpcBlock::new(
-                None,
+            build_rpc_block(
                 snapshots[block_index].beacon_block.clone(),
-                chain_segment_blobs[block_index].clone(),
-            )
-            .unwrap(),
+                &chain_segment_blobs[block_index],
+                &harness.spec,
+            ),
             NotifyExecutionLayer::Yes,
             BlockImportSource::Lookup,
             || Ok(()),
         )
         .await;
     assert!(
-        matches!(process_res, Err(BlockError::InvalidSignature)),
+        matches!(
+            process_res,
+            Err(BlockError::InvalidSignature(
+                InvalidSignature::BlockBodySignatures
+            ))
+        ),
         "should not import individual block with an invalid {} signature, got: {:?}",
         item,
         process_res
@@ -524,7 +562,7 @@ async fn invalid_signature_gossip_block() {
             .take(block_index)
             .zip(chain_segment_blobs.iter())
             .map(|(snapshot, blobs)| {
-                RpcBlock::new(None, snapshot.beacon_block.clone(), blobs.clone()).unwrap()
+                build_rpc_block(snapshot.beacon_block.clone(), blobs, &harness.spec)
             })
             .collect();
         harness
@@ -534,21 +572,25 @@ async fn invalid_signature_gossip_block() {
             .into_block_error()
             .expect("should import all blocks prior to the one being tested");
         let signed_block = SignedBeaconBlock::from_block(block, junk_signature());
+        let process_res = harness
+            .chain
+            .process_block(
+                signed_block.canonical_root(),
+                Arc::new(signed_block),
+                NotifyExecutionLayer::Yes,
+                BlockImportSource::Lookup,
+                || Ok(()),
+            )
+            .await;
         assert!(
             matches!(
-                harness
-                    .chain
-                    .process_block(
-                        signed_block.canonical_root(),
-                        Arc::new(signed_block),
-                        NotifyExecutionLayer::Yes,
-                        BlockImportSource::Lookup,
-                        || Ok(()),
-                    )
-                    .await,
-                Err(BlockError::InvalidSignature)
+                process_res,
+                Err(BlockError::InvalidSignature(
+                    InvalidSignature::ProposerSignature
+                ))
             ),
-            "should not import individual block with an invalid gossip signature",
+            "should not import individual block with an invalid gossip signature, got: {:?}",
+            process_res
         );
     }
 }
@@ -572,20 +614,22 @@ async fn invalid_signature_block_proposal() {
             .iter()
             .zip(chain_segment_blobs.iter())
             .map(|(snapshot, blobs)| {
-                RpcBlock::new(None, snapshot.beacon_block.clone(), blobs.clone()).unwrap()
+                build_rpc_block(snapshot.beacon_block.clone(), blobs, &harness.spec)
             })
             .collect::<Vec<_>>();
         // Ensure the block will be rejected if imported in a chain segment.
+        let process_res = harness
+            .chain
+            .process_chain_segment(blocks, NotifyExecutionLayer::Yes)
+            .await
+            .into_block_error();
         assert!(
             matches!(
-                harness
-                    .chain
-                    .process_chain_segment(blocks, NotifyExecutionLayer::Yes)
-                    .await
-                    .into_block_error(),
-                Err(BlockError::InvalidSignature)
+                process_res,
+                Err(BlockError::InvalidSignature(InvalidSignature::Unknown))
             ),
-            "should not import chain segment with an invalid block signature",
+            "should not import chain segment with an invalid block signature, got: {:?}",
+            process_res
         );
     }
 }
@@ -754,6 +798,11 @@ async fn invalid_signature_attester_slashing() {
                     .push(attester_slashing.as_electra().unwrap().clone())
                     .expect("should update attester slashing");
             }
+            BeaconBlockBodyRefMut::Fulu(ref mut blk) => {
+                blk.attester_slashings
+                    .push(attester_slashing.as_electra().unwrap().clone())
+                    .expect("should update attester slashing");
+            }
         }
         snapshots[block_index].beacon_block =
             Arc::new(SignedBeaconBlock::from_block(block, signature));
@@ -809,6 +858,10 @@ async fn invalid_signature_attestation() {
                 .attestations
                 .get_mut(0)
                 .map(|att| att.signature = junk_aggregate_signature()),
+            BeaconBlockBodyRefMut::Fulu(ref mut blk) => blk
+                .attestations
+                .get_mut(0)
+                .map(|att| att.signature = junk_aggregate_signature()),
         };
 
         if block.body().attestations_len() > 0 {
@@ -869,7 +922,7 @@ async fn invalid_signature_deposit() {
             .iter()
             .zip(chain_segment_blobs.iter())
             .map(|(snapshot, blobs)| {
-                RpcBlock::new(None, snapshot.beacon_block.clone(), blobs.clone()).unwrap()
+                build_rpc_block(snapshot.beacon_block.clone(), blobs, &harness.spec)
             })
             .collect();
         assert!(
@@ -879,7 +932,7 @@ async fn invalid_signature_deposit() {
                     .process_chain_segment(blocks, NotifyExecutionLayer::Yes)
                     .await
                     .into_block_error(),
-                Err(BlockError::InvalidSignature)
+                Err(BlockError::InvalidSignature(InvalidSignature::Unknown))
             ),
             "should not throw an invalid signature error for a bad deposit signature"
         );
@@ -935,7 +988,7 @@ fn unwrap_err<T, U>(result: Result<T, U>) -> U {
 #[tokio::test]
 async fn block_gossip_verification() {
     let harness = get_harness(VALIDATOR_COUNT);
-    let (chain_segment, chain_segment_blobs) = get_chain_segment_with_blob_sidecars().await;
+    let (chain_segment, chain_segment_blobs) = get_chain_segment().await;
 
     let block_index = CHAIN_SEGMENT_LENGTH - 2;
 
@@ -947,7 +1000,7 @@ async fn block_gossip_verification() {
     // Import the ancestors prior to the block we're testing.
     for (snapshot, blobs_opt) in chain_segment[0..block_index]
         .iter()
-        .zip(chain_segment_blobs.iter())
+        .zip(chain_segment_blobs.into_iter())
     {
         let gossip_verified = harness
             .chain
@@ -966,20 +1019,8 @@ async fn block_gossip_verification() {
             )
             .await
             .expect("should import valid gossip verified block");
-        if let Some(blob_sidecars) = blobs_opt {
-            for blob_sidecar in blob_sidecars {
-                let blob_index = blob_sidecar.index;
-                let gossip_verified = harness
-                    .chain
-                    .verify_blob_sidecar_for_gossip(blob_sidecar.clone(), blob_index)
-                    .expect("should obtain gossip verified blob");
-
-                harness
-                    .chain
-                    .process_gossip_blob(gossip_verified)
-                    .await
-                    .expect("should import valid gossip verified blob");
-            }
+        if let Some(data_sidecars) = blobs_opt {
+            verify_and_process_gossip_data_sidecars(&harness, data_sidecars).await;
         }
     }
 
@@ -1075,7 +1116,7 @@ async fn block_gossip_verification() {
                     )))
                     .await
             ),
-            BlockError::ProposalSignatureInvalid
+            BlockError::InvalidSignature(InvalidSignature::ProposerSignature)
         ),
         "should not import a block with an invalid proposal signature"
     );
@@ -1207,6 +1248,51 @@ async fn block_gossip_verification() {
     );
 }
 
+async fn verify_and_process_gossip_data_sidecars(
+    harness: &BeaconChainHarness<EphemeralHarnessType<E>>,
+    data_sidecars: DataSidecars<E>,
+) {
+    match data_sidecars {
+        DataSidecars::Blobs(blob_sidecars) => {
+            for blob_sidecar in blob_sidecars {
+                let blob_index = blob_sidecar.index;
+                let gossip_verified = harness
+                    .chain
+                    .verify_blob_sidecar_for_gossip(blob_sidecar.clone(), blob_index)
+                    .expect("should obtain gossip verified blob");
+
+                harness
+                    .chain
+                    .process_gossip_blob(gossip_verified)
+                    .await
+                    .expect("should import valid gossip verified blob");
+            }
+        }
+        DataSidecars::DataColumns(column_sidecars) => {
+            let gossip_verified = column_sidecars
+                .into_iter()
+                .map(|column_sidecar| {
+                    let subnet_id = DataColumnSubnetId::from_column_index(
+                        column_sidecar.index(),
+                        &harness.spec,
+                    );
+                    harness.chain.verify_data_column_sidecar_for_gossip(
+                        column_sidecar.into_inner(),
+                        *subnet_id,
+                    )
+                })
+                .collect::<Result<Vec<_>, _>>()
+                .expect("should obtain gossip verified columns");
+
+            harness
+                .chain
+                .process_gossip_data_columns(gossip_verified, || Ok(()))
+                .await
+                .expect("should import valid gossip verified columns");
+        }
+    }
+}
+
 #[tokio::test]
 async fn verify_block_for_gossip_slashing_detection() {
     let slasher_dir = tempdir().unwrap();
@@ -1214,7 +1300,7 @@ async fn verify_block_for_gossip_slashing_detection() {
     let slasher = Arc::new(
         Slasher::open(
             SlasherConfig::new(slasher_dir.path().into()),
-            spec,
+            spec.clone(),
             test_logger(),
         )
         .unwrap(),
@@ -1237,20 +1323,14 @@ async fn verify_block_for_gossip_slashing_detection() {
     let verified_block = harness.chain.verify_block_for_gossip(block1).await.unwrap();
 
     if let Some((kzg_proofs, blobs)) = blobs1 {
-        let sidecars =
-            BlobSidecar::build_sidecars(blobs, verified_block.block(), kzg_proofs).unwrap();
-        for sidecar in sidecars {
-            let blob_index = sidecar.index;
-            let verified_blob = harness
-                .chain
-                .verify_blob_sidecar_for_gossip(sidecar, blob_index)
-                .unwrap();
-            harness
-                .chain
-                .process_gossip_blob(verified_blob)
-                .await
-                .unwrap();
-        }
+        harness
+            .process_gossip_blobs_or_columns(
+                verified_block.block(),
+                blobs.iter(),
+                kzg_proofs.iter(),
+                None,
+            )
+            .await;
     }
     harness
         .chain
@@ -1726,7 +1806,7 @@ async fn import_execution_pending_block<T: BeaconChainTypes>(
         .unwrap()
     {
         ExecutedBlock::Available(block) => chain
-            .import_available_block(Box::from(block), None)
+            .import_available_block(Box::from(block))
             .await
             .map_err(|e| format!("{e:?}")),
         ExecutedBlock::AvailabilityPending(_) => {
diff --git a/beacon_node/beacon_chain/tests/events.rs b/beacon_node/beacon_chain/tests/events.rs
index ab784d3be4..c9bd55e062 100644
--- a/beacon_node/beacon_chain/tests/events.rs
+++ b/beacon_node/beacon_chain/tests/events.rs
@@ -73,7 +73,7 @@ async fn blob_sidecar_event_on_process_rpc_blobs() {
     let blob_1 = Arc::new(blob_1);
     let blob_2 = Arc::new(blob_2);
 
-    let blobs = FixedBlobSidecarList::from(vec![Some(blob_1.clone()), Some(blob_2.clone())]);
+    let blobs = FixedBlobSidecarList::new(vec![Some(blob_1.clone()), Some(blob_2.clone())]);
     let expected_sse_blobs = vec![
         SseBlobSidecar::from_blob_sidecar(blob_1.as_ref()),
         SseBlobSidecar::from_blob_sidecar(blob_2.as_ref()),
diff --git a/beacon_node/beacon_chain/tests/op_verification.rs b/beacon_node/beacon_chain/tests/op_verification.rs
index df0d561e1c..44fb298d6c 100644
--- a/beacon_node/beacon_chain/tests/op_verification.rs
+++ b/beacon_node/beacon_chain/tests/op_verification.rs
@@ -14,7 +14,8 @@ use state_processing::per_block_processing::errors::{
     AttesterSlashingInvalid, BlockOperationError, ExitInvalid, ProposerSlashingInvalid,
 };
 use std::sync::{Arc, LazyLock};
-use store::{LevelDB, StoreConfig};
+use store::database::interface::BeaconNodeBackend;
+use store::StoreConfig;
 use tempfile::{tempdir, TempDir};
 use types::*;
 
@@ -26,7 +27,7 @@ static KEYPAIRS: LazyLock<Vec<Keypair>> =
 
 type E = MinimalEthSpec;
 type TestHarness = BeaconChainHarness<DiskHarnessType<E>>;
-type HotColdDB = store::HotColdDB<E, LevelDB<E>, LevelDB<E>>;
+type HotColdDB = store::HotColdDB<E, BeaconNodeBackend<E>, BeaconNodeBackend<E>>;
 
 fn get_store(db_path: &TempDir) -> Arc<HotColdDB> {
     let spec = Arc::new(test_spec::<E>());
diff --git a/beacon_node/beacon_chain/tests/store_tests.rs b/beacon_node/beacon_chain/tests/store_tests.rs
index e1258ccdea..8654b33646 100644
--- a/beacon_node/beacon_chain/tests/store_tests.rs
+++ b/beacon_node/beacon_chain/tests/store_tests.rs
@@ -1,7 +1,6 @@
 #![cfg(not(debug_assertions))]
 
 use beacon_chain::attestation_verification::Error as AttnError;
-use beacon_chain::block_verification_types::RpcBlock;
 use beacon_chain::builder::BeaconChainBuilder;
 use beacon_chain::data_availability_checker::AvailableBlock;
 use beacon_chain::schema_change::migrate_schema;
@@ -25,10 +24,11 @@ use std::collections::HashSet;
 use std::convert::TryInto;
 use std::sync::{Arc, LazyLock};
 use std::time::Duration;
+use store::database::interface::BeaconNodeBackend;
 use store::metadata::{SchemaVersion, CURRENT_SCHEMA_VERSION, STATE_UPPER_LIMIT_NO_RETAIN};
 use store::{
     iter::{BlockRootsIterator, StateRootsIterator},
-    BlobInfo, DBColumn, HotColdDB, LevelDB, StoreConfig,
+    BlobInfo, DBColumn, HotColdDB, StoreConfig,
 };
 use tempfile::{tempdir, TempDir};
 use tokio::time::sleep;
@@ -46,7 +46,7 @@ static KEYPAIRS: LazyLock<Vec<Keypair>> =
 type E = MinimalEthSpec;
 type TestHarness = BeaconChainHarness<DiskHarnessType<E>>;
 
-fn get_store(db_path: &TempDir) -> Arc<HotColdDB<E, LevelDB<E>, LevelDB<E>>> {
+fn get_store(db_path: &TempDir) -> Arc<HotColdDB<E, BeaconNodeBackend<E>, BeaconNodeBackend<E>>> {
     get_store_generic(db_path, StoreConfig::default(), test_spec::<E>())
 }
 
@@ -54,7 +54,7 @@ fn get_store_generic(
     db_path: &TempDir,
     config: StoreConfig,
     spec: ChainSpec,
-) -> Arc<HotColdDB<E, LevelDB<E>, LevelDB<E>>> {
+) -> Arc<HotColdDB<E, BeaconNodeBackend<E>, BeaconNodeBackend<E>>> {
     let hot_path = db_path.path().join("chain_db");
     let cold_path = db_path.path().join("freezer_db");
     let blobs_path = db_path.path().join("blobs_db");
@@ -73,7 +73,7 @@ fn get_store_generic(
 }
 
 fn get_harness(
-    store: Arc<HotColdDB<E, LevelDB<E>, LevelDB<E>>>,
+    store: Arc<HotColdDB<E, BeaconNodeBackend<E>, BeaconNodeBackend<E>>>,
     validator_count: usize,
 ) -> TestHarness {
     // Most tests expect to retain historic states, so we use this as the default.
@@ -81,13 +81,26 @@ fn get_harness(
         reconstruct_historic_states: true,
         ..ChainConfig::default()
     };
-    get_harness_generic(store, validator_count, chain_config)
+    get_harness_generic(store, validator_count, chain_config, false)
+}
+
+fn get_harness_import_all_data_columns(
+    store: Arc<HotColdDB<E, BeaconNodeBackend<E>, BeaconNodeBackend<E>>>,
+    validator_count: usize,
+) -> TestHarness {
+    // Most tests expect to retain historic states, so we use this as the default.
+    let chain_config = ChainConfig {
+        reconstruct_historic_states: true,
+        ..ChainConfig::default()
+    };
+    get_harness_generic(store, validator_count, chain_config, true)
 }
 
 fn get_harness_generic(
-    store: Arc<HotColdDB<E, LevelDB<E>, LevelDB<E>>>,
+    store: Arc<HotColdDB<E, BeaconNodeBackend<E>, BeaconNodeBackend<E>>>,
     validator_count: usize,
     chain_config: ChainConfig,
+    import_all_data_columns: bool,
 ) -> TestHarness {
     let harness = TestHarness::builder(MinimalEthSpec)
         .spec(store.get_chain_spec().clone())
@@ -96,6 +109,7 @@ fn get_harness_generic(
         .fresh_disk_store(store)
         .mock_execution_layer()
         .chain_config(chain_config)
+        .import_all_data_columns(import_all_data_columns)
         .build();
     harness.advance_slot();
     harness
@@ -147,6 +161,7 @@ async fn light_client_bootstrap_test() {
         LightClientBootstrap::Capella(lc_bootstrap) => lc_bootstrap.header.beacon.slot,
         LightClientBootstrap::Deneb(lc_bootstrap) => lc_bootstrap.header.beacon.slot,
         LightClientBootstrap::Electra(lc_bootstrap) => lc_bootstrap.header.beacon.slot,
+        LightClientBootstrap::Fulu(lc_bootstrap) => lc_bootstrap.header.beacon.slot,
     };
 
     assert_eq!(
@@ -243,7 +258,6 @@ async fn full_participation_no_skips() {
             AttestationStrategy::AllValidators,
         )
         .await;
-
     check_finalization(&harness, num_blocks_produced);
     check_split_slot(&harness, store);
     check_chain_dump(&harness, num_blocks_produced + 1);
@@ -2285,7 +2299,12 @@ async fn weak_subjectivity_sync_test(slots: Vec<Slot>, checkpoint_slot: Slot) {
 
     let temp1 = tempdir().unwrap();
     let full_store = get_store(&temp1);
-    let harness = get_harness(full_store.clone(), LOW_VALIDATOR_COUNT);
+
+    // TODO(das): Run a supernode so the node has full blobs stored.
+    // This may not be required in the future if we end up implementing downloading checkpoint
+    // blobs from p2p peers:
+    // https://github.com/sigp/lighthouse/issues/6837
+    let harness = get_harness_import_all_data_columns(full_store.clone(), LOW_VALIDATOR_COUNT);
 
     let all_validators = (0..LOW_VALIDATOR_COUNT).collect::<Vec<_>>();
 
@@ -2316,7 +2335,10 @@ async fn weak_subjectivity_sync_test(slots: Vec<Slot>, checkpoint_slot: Slot) {
         .get_full_block(&wss_block_root)
         .unwrap()
         .unwrap();
-    let wss_blobs_opt = harness.chain.store.get_blobs(&wss_block_root).unwrap();
+    let wss_blobs_opt = harness
+        .chain
+        .get_or_reconstruct_blobs(&wss_block_root)
+        .unwrap();
     let wss_state = full_store
         .get_state(&wss_state_root, Some(checkpoint_slot))
         .unwrap()
@@ -2341,8 +2363,10 @@ async fn weak_subjectivity_sync_test(slots: Vec<Slot>, checkpoint_slot: Slot) {
 
     let kzg = get_kzg(&spec);
 
-    let mock =
-        mock_execution_layer_from_parts(&harness.spec, harness.runtime.task_executor.clone());
+    let mock = mock_execution_layer_from_parts(
+        harness.spec.clone(),
+        harness.runtime.task_executor.clone(),
+    );
 
     // Initialise a new beacon chain from the finalized checkpoint.
     // The slot clock must be set to a time ahead of the checkpoint state.
@@ -2387,10 +2411,16 @@ async fn weak_subjectivity_sync_test(slots: Vec<Slot>, checkpoint_slot: Slot) {
         .await
         .unwrap()
         .unwrap();
-    let store_wss_blobs_opt = beacon_chain.store.get_blobs(&wss_block_root).unwrap();
+    // This test may break in the future if we no longer store the full checkpoint data columns.
+    let store_wss_blobs_opt = beacon_chain
+        .get_or_reconstruct_blobs(&wss_block_root)
+        .unwrap();
 
     assert_eq!(store_wss_block, wss_block);
-    assert_eq!(store_wss_blobs_opt, wss_blobs_opt);
+    // TODO(fulu): Remove this condition once #6760 (PeerDAS checkpoint sync) is merged.
+    if !beacon_chain.spec.is_peer_das_scheduled() {
+        assert_eq!(store_wss_blobs_opt, wss_blobs_opt);
+    }
 
     // Apply blocks forward to reach head.
     let chain_dump = harness.chain.chain_dump().unwrap();
@@ -2406,7 +2436,7 @@ async fn weak_subjectivity_sync_test(slots: Vec<Slot>, checkpoint_slot: Slot) {
             .await
             .unwrap()
             .unwrap();
-        let blobs = harness.chain.get_blobs(&block_root).expect("blobs");
+
         let slot = full_block.slot();
         let state_root = full_block.state_root();
 
@@ -2414,7 +2444,7 @@ async fn weak_subjectivity_sync_test(slots: Vec<Slot>, checkpoint_slot: Slot) {
         beacon_chain
             .process_block(
                 full_block.canonical_root(),
-                RpcBlock::new(Some(block_root), Arc::new(full_block), Some(blobs)).unwrap(),
+                harness.build_rpc_block_from_store_blobs(Some(block_root), Arc::new(full_block)),
                 NotifyExecutionLayer::Yes,
                 BlockImportSource::Lookup,
                 || Ok(()),
@@ -2468,13 +2498,12 @@ async fn weak_subjectivity_sync_test(slots: Vec<Slot>, checkpoint_slot: Slot) {
             .await
             .expect("should get block")
             .expect("should get block");
-        let blobs = harness.chain.get_blobs(&block_root).expect("blobs");
 
         if let MaybeAvailableBlock::Available(block) = harness
             .chain
             .data_availability_checker
             .verify_kzg_for_rpc_block(
-                RpcBlock::new(Some(block_root), Arc::new(full_block), Some(blobs)).unwrap(),
+                harness.build_rpc_block_from_store_blobs(Some(block_root), Arc::new(full_block)),
             )
             .expect("should verify kzg")
         {
@@ -2575,7 +2604,7 @@ async fn process_blocks_and_attestations_for_unaligned_checkpoint() {
         reconstruct_historic_states: false,
         ..ChainConfig::default()
     };
-    let harness = get_harness_generic(store.clone(), LOW_VALIDATOR_COUNT, chain_config);
+    let harness = get_harness_generic(store.clone(), LOW_VALIDATOR_COUNT, chain_config, false);
 
     let all_validators = (0..LOW_VALIDATOR_COUNT).collect::<Vec<_>>();
 
@@ -3063,6 +3092,10 @@ async fn deneb_prune_blobs_happy_case() {
     let db_path = tempdir().unwrap();
     let store = get_store(&db_path);
 
+    if store.get_chain_spec().is_peer_das_scheduled() {
+        // TODO(fulu): add prune tests for Fulu / PeerDAS data columns.
+        return;
+    }
     let Some(deneb_fork_epoch) = store.get_chain_spec().deneb_fork_epoch else {
         // No-op prior to Deneb.
         return;
@@ -3110,6 +3143,10 @@ async fn deneb_prune_blobs_no_finalization() {
     let db_path = tempdir().unwrap();
     let store = get_store(&db_path);
 
+    if store.get_chain_spec().is_peer_das_scheduled() {
+        // TODO(fulu): add prune tests for Fulu / PeerDAS data columns.
+        return;
+    }
     let Some(deneb_fork_epoch) = store.get_chain_spec().deneb_fork_epoch else {
         // No-op prior to Deneb.
         return;
@@ -3254,6 +3291,10 @@ async fn deneb_prune_blobs_margin_test(margin: u64) {
     let db_path = tempdir().unwrap();
     let store = get_store_generic(&db_path, config, test_spec::<E>());
 
+    if store.get_chain_spec().is_peer_das_scheduled() {
+        // TODO(fulu): add prune tests for Fulu / PeerDAS data columns.
+        return;
+    }
     let Some(deneb_fork_epoch) = store.get_chain_spec().deneb_fork_epoch else {
         // No-op prior to Deneb.
         return;
@@ -3350,7 +3391,7 @@ fn check_blob_existence(
         .unwrap()
         .map(Result::unwrap)
     {
-        if let Some(blobs) = harness.chain.store.get_blobs(&block_root).unwrap() {
+        if let Some(blobs) = harness.chain.store.get_blobs(&block_root).unwrap().blobs() {
             assert!(should_exist, "blobs at slot {slot} exist but should not");
             blobs_seen += blobs.len();
         } else {
@@ -3496,7 +3537,10 @@ fn check_finalization(harness: &TestHarness, expected_slot: u64) {
 }
 
 /// Check that the HotColdDB's split_slot is equal to the start slot of the last finalized epoch.
-fn check_split_slot(harness: &TestHarness, store: Arc<HotColdDB<E, LevelDB<E>, LevelDB<E>>>) {
+fn check_split_slot(
+    harness: &TestHarness,
+    store: Arc<HotColdDB<E, BeaconNodeBackend<E>, BeaconNodeBackend<E>>>,
+) {
     let split_slot = store.get_split_slot();
     assert_eq!(
         harness
diff --git a/beacon_node/beacon_chain/tests/validator_monitor.rs b/beacon_node/beacon_chain/tests/validator_monitor.rs
index b4a54d2667..180db6d76d 100644
--- a/beacon_node/beacon_chain/tests/validator_monitor.rs
+++ b/beacon_node/beacon_chain/tests/validator_monitor.rs
@@ -4,7 +4,7 @@ use beacon_chain::test_utils::{
 use beacon_chain::validator_monitor::{ValidatorMonitorConfig, MISSED_BLOCK_LAG_SLOTS};
 use logging::test_logger;
 use std::sync::LazyLock;
-use types::{Epoch, EthSpec, ForkName, Keypair, MainnetEthSpec, PublicKeyBytes, Slot};
+use types::{Epoch, EthSpec, Keypair, MainnetEthSpec, PublicKeyBytes, Slot};
 
 // Should ideally be divisible by 3.
 pub const VALIDATOR_COUNT: usize = 48;
@@ -117,7 +117,7 @@ async fn missed_blocks_across_epochs() {
 }
 
 #[tokio::test]
-async fn produces_missed_blocks() {
+async fn missed_blocks_basic() {
     let validator_count = 16;
 
     let slots_per_epoch = E::slots_per_epoch();
@@ -127,13 +127,10 @@ async fn produces_missed_blocks() {
     // Generate 63 slots (2 epochs * 32 slots per epoch - 1)
     let initial_blocks = slots_per_epoch * nb_epoch_to_simulate.as_u64() - 1;
 
-    // The validator index of the validator that is 'supposed' to miss a block
-    let validator_index_to_monitor = 1;
-
     // 1st scenario //
     //
     // Missed block happens when slot and prev_slot are in the same epoch
-    let harness1 = get_harness(validator_count, vec![validator_index_to_monitor]);
+    let harness1 = get_harness(validator_count, vec![]);
     harness1
         .extend_chain(
             initial_blocks as usize,
@@ -153,7 +150,7 @@ async fn produces_missed_blocks() {
     let mut prev_slot = Slot::new(idx - 1);
     let mut duplicate_block_root = *_state.block_roots().get(idx as usize).unwrap();
     let mut validator_indexes = _state.get_beacon_proposer_indices(&harness1.spec).unwrap();
-    let mut validator_index = validator_indexes[slot_in_epoch.as_usize()];
+    let mut missed_block_proposer = validator_indexes[slot_in_epoch.as_usize()];
     let mut proposer_shuffling_decision_root = _state
         .proposer_shuffling_decision_root(duplicate_block_root)
         .unwrap();
@@ -170,7 +167,7 @@ async fn produces_missed_blocks() {
         beacon_proposer_cache.lock().insert(
             epoch,
             proposer_shuffling_decision_root,
-            validator_indexes.into_iter().collect::<Vec<usize>>(),
+            validator_indexes,
             _state.fork()
         ),
         Ok(())
@@ -187,12 +184,15 @@ async fn produces_missed_blocks() {
         // Let's validate the state which will call the function responsible for
         // adding the missed blocks to the validator monitor
         let mut validator_monitor = harness1.chain.validator_monitor.write();
+
+        validator_monitor.add_validator_pubkey(KEYPAIRS[missed_block_proposer].pk.compress());
         validator_monitor.process_valid_state(nb_epoch_to_simulate, _state, &harness1.chain.spec);
 
         // We should have one entry in the missed blocks map
         assert_eq!(
-            validator_monitor.get_monitored_validator_missed_block_count(validator_index as u64),
-            1
+            validator_monitor
+                .get_monitored_validator_missed_block_count(missed_block_proposer as u64),
+            1,
         );
     }
 
@@ -201,22 +201,7 @@ async fn produces_missed_blocks() {
     // Missed block happens when slot and prev_slot are not in the same epoch
     // making sure that the cache reloads when the epoch changes
     // in that scenario the slot that missed a block is the first slot of the epoch
-    // We are adding other validators to monitor as these ones will miss a block depending on
-    // the fork name specified when running the test as the proposer cache differs depending on
-    // the fork name (cf. seed)
-    //
-    // If you are adding a new fork and seeing errors, print
-    // `validator_indexes[slot_in_epoch.as_usize()]` and add it below.
-    let validator_index_to_monitor = match harness1.spec.fork_name_at_slot::<E>(Slot::new(0)) {
-        ForkName::Base => 7,
-        ForkName::Altair => 2,
-        ForkName::Bellatrix => 4,
-        ForkName::Capella => 11,
-        ForkName::Deneb => 3,
-        ForkName::Electra => 1,
-    };
-
-    let harness2 = get_harness(validator_count, vec![validator_index_to_monitor]);
+    let harness2 = get_harness(validator_count, vec![]);
     let advance_slot_by = 9;
     harness2
         .extend_chain(
@@ -237,11 +222,7 @@ async fn produces_missed_blocks() {
     slot_in_epoch = slot % slots_per_epoch;
     duplicate_block_root = *_state2.block_roots().get(idx as usize).unwrap();
     validator_indexes = _state2.get_beacon_proposer_indices(&harness2.spec).unwrap();
-    validator_index = validator_indexes[slot_in_epoch.as_usize()];
-    // If you are adding a new fork and seeing errors, it means the fork seed has changed the
-    // validator_index. Uncomment this line, run the test again and add the resulting index to the
-    // list above.
-    //eprintln!("new index which needs to be added => {:?}", validator_index);
+    missed_block_proposer = validator_indexes[slot_in_epoch.as_usize()];
 
     let beacon_proposer_cache = harness2
         .chain
@@ -255,7 +236,7 @@ async fn produces_missed_blocks() {
         beacon_proposer_cache.lock().insert(
             epoch,
             duplicate_block_root,
-            validator_indexes.into_iter().collect::<Vec<usize>>(),
+            validator_indexes.clone(),
             _state2.fork()
         ),
         Ok(())
@@ -270,10 +251,12 @@ async fn produces_missed_blocks() {
         // Let's validate the state which will call the function responsible for
         // adding the missed blocks to the validator monitor
         let mut validator_monitor2 = harness2.chain.validator_monitor.write();
+        validator_monitor2.add_validator_pubkey(KEYPAIRS[missed_block_proposer].pk.compress());
         validator_monitor2.process_valid_state(epoch, _state2, &harness2.chain.spec);
         // We should have one entry in the missed blocks map
         assert_eq!(
-            validator_monitor2.get_monitored_validator_missed_block_count(validator_index as u64),
+            validator_monitor2
+                .get_monitored_validator_missed_block_count(missed_block_proposer as u64),
             1
         );
 
@@ -281,19 +264,20 @@ async fn produces_missed_blocks() {
         //
         // A missed block happens but the validator is not monitored
         // it should not be flagged as a missed block
-        idx = initial_blocks + (advance_slot_by) - 7;
+        while validator_indexes[(idx % slots_per_epoch) as usize] == missed_block_proposer
+            && idx / slots_per_epoch == epoch.as_u64()
+        {
+            idx += 1;
+        }
         slot = Slot::new(idx);
         prev_slot = Slot::new(idx - 1);
         slot_in_epoch = slot % slots_per_epoch;
         duplicate_block_root = *_state2.block_roots().get(idx as usize).unwrap();
-        validator_indexes = _state2.get_beacon_proposer_indices(&harness2.spec).unwrap();
-        let not_monitored_validator_index = validator_indexes[slot_in_epoch.as_usize()];
-        // This could do with a refactor: https://github.com/sigp/lighthouse/issues/6293
-        assert_ne!(
-            not_monitored_validator_index,
-            validator_index_to_monitor,
-            "this test has a fragile dependency on hardcoded indices. you need to tweak some settings or rewrite this"
-        );
+        let second_missed_block_proposer = validator_indexes[slot_in_epoch.as_usize()];
+
+        // This test may fail if we can't find another distinct proposer in the same epoch.
+        // However, this should be vanishingly unlikely: P ~= (1/16)^32 = 2e-39.
+        assert_ne!(missed_block_proposer, second_missed_block_proposer);
 
         assert_eq!(
             _state2.set_block_root(prev_slot, duplicate_block_root),
@@ -305,10 +289,9 @@ async fn produces_missed_blocks() {
         validator_monitor2.process_valid_state(epoch, _state2, &harness2.chain.spec);
 
         // We shouldn't have any entry in the missed blocks map
-        assert_ne!(validator_index, not_monitored_validator_index);
         assert_eq!(
             validator_monitor2
-                .get_monitored_validator_missed_block_count(not_monitored_validator_index as u64),
+                .get_monitored_validator_missed_block_count(second_missed_block_proposer as u64),
             0
         );
     }
@@ -317,7 +300,7 @@ async fn produces_missed_blocks() {
     //
     // A missed block happens at state.slot - LOG_SLOTS_PER_EPOCH
     // it shouldn't be flagged as a missed block
-    let harness3 = get_harness(validator_count, vec![validator_index_to_monitor]);
+    let harness3 = get_harness(validator_count, vec![]);
     harness3
         .extend_chain(
             slots_per_epoch as usize,
@@ -337,7 +320,7 @@ async fn produces_missed_blocks() {
     prev_slot = Slot::new(idx - 1);
     duplicate_block_root = *_state3.block_roots().get(idx as usize).unwrap();
     validator_indexes = _state3.get_beacon_proposer_indices(&harness3.spec).unwrap();
-    validator_index = validator_indexes[slot_in_epoch.as_usize()];
+    missed_block_proposer = validator_indexes[slot_in_epoch.as_usize()];
     proposer_shuffling_decision_root = _state3
         .proposer_shuffling_decision_root_at_epoch(epoch, duplicate_block_root)
         .unwrap();
@@ -354,7 +337,7 @@ async fn produces_missed_blocks() {
         beacon_proposer_cache.lock().insert(
             epoch,
             proposer_shuffling_decision_root,
-            validator_indexes.into_iter().collect::<Vec<usize>>(),
+            validator_indexes,
             _state3.fork()
         ),
         Ok(())
@@ -371,11 +354,13 @@ async fn produces_missed_blocks() {
         // Let's validate the state which will call the function responsible for
         // adding the missed blocks to the validator monitor
         let mut validator_monitor3 = harness3.chain.validator_monitor.write();
+        validator_monitor3.add_validator_pubkey(KEYPAIRS[missed_block_proposer].pk.compress());
         validator_monitor3.process_valid_state(epoch, _state3, &harness3.chain.spec);
 
         // We shouldn't have one entry in the missed blocks map
         assert_eq!(
-            validator_monitor3.get_monitored_validator_missed_block_count(validator_index as u64),
+            validator_monitor3
+                .get_monitored_validator_missed_block_count(missed_block_proposer as u64),
             0
         );
     }
diff --git a/beacon_node/beacon_processor/src/lib.rs b/beacon_node/beacon_processor/src/lib.rs
index d83426a274..cbd9e0b872 100644
--- a/beacon_node/beacon_processor/src/lib.rs
+++ b/beacon_node/beacon_processor/src/lib.rs
@@ -1030,7 +1030,7 @@ impl<E: EthSpec> BeaconProcessor<E> {
                 let can_spawn = self.current_workers < self.config.max_workers;
                 let drop_during_sync = work_event
                     .as_ref()
-                    .map_or(false, |event| event.drop_during_sync);
+                    .is_some_and(|event| event.drop_during_sync);
 
                 let idle_tx = idle_tx.clone();
                 let modified_queue_id = match work_event {
@@ -1731,7 +1731,7 @@ mod tests {
     #[test]
     fn min_queue_len() {
         // State with no validators.
-        let spec = ForkName::latest().make_genesis_spec(ChainSpec::mainnet());
+        let spec = ForkName::latest_stable().make_genesis_spec(ChainSpec::mainnet());
         let genesis_time = 0;
         let state = BeaconState::<MainnetEthSpec>::new(genesis_time, Eth1Data::default(), &spec);
         assert_eq!(state.validators().len(), 0);
diff --git a/beacon_node/client/src/builder.rs b/beacon_node/client/src/builder.rs
index 7c6a253aca..e3bfd60a48 100644
--- a/beacon_node/client/src/builder.rs
+++ b/beacon_node/client/src/builder.rs
@@ -14,7 +14,7 @@ use beacon_chain::{
     eth1_chain::{CachingEth1Backend, Eth1Chain},
     slot_clock::{SlotClock, SystemTimeSlotClock},
     state_advance_timer::spawn_state_advance_timer,
-    store::{HotColdDB, ItemStore, LevelDB, StoreConfig},
+    store::{HotColdDB, ItemStore, StoreConfig},
     BeaconChain, BeaconChainTypes, Eth1ChainBackend, MigratorConfig, ServerSentEventHandler,
 };
 use beacon_chain::{Kzg, LightClientProducerEvent};
@@ -36,12 +36,12 @@ use network::{NetworkConfig, NetworkSenders, NetworkService};
 use slasher::Slasher;
 use slasher_service::SlasherService;
 use slog::{debug, info, warn, Logger};
-use ssz::Decode;
 use std::net::TcpListener;
 use std::path::{Path, PathBuf};
 use std::sync::Arc;
 use std::time::Duration;
 use std::time::{SystemTime, UNIX_EPOCH};
+use store::database::interface::BeaconNodeBackend;
 use timer::spawn_timer;
 use tokio::sync::oneshot;
 use types::{
@@ -361,10 +361,11 @@ where
                 let anchor_block = SignedBeaconBlock::from_ssz_bytes(&anchor_block_bytes, &spec)
                     .map_err(|e| format!("Unable to parse weak subj block SSZ: {:?}", e))?;
                 let anchor_blobs = if anchor_block.message().body().has_blobs() {
+                    let max_blobs_len = spec.max_blobs_per_block(anchor_block.epoch()) as usize;
                     let anchor_blobs_bytes = anchor_blobs_bytes
                         .ok_or("Blobs for checkpoint must be provided using --checkpoint-blobs")?;
                     Some(
-                        BlobSidecarList::from_ssz_bytes(&anchor_blobs_bytes)
+                        BlobSidecarList::from_ssz_bytes(&anchor_blobs_bytes, max_blobs_len)
                             .map_err(|e| format!("Unable to parse weak subj blobs SSZ: {e:?}"))?,
                     )
                 } else {
@@ -910,7 +911,7 @@ where
                         .forkchoice_update_parameters();
                     if params
                         .head_hash
-                        .map_or(false, |hash| hash != ExecutionBlockHash::zero())
+                        .is_some_and(|hash| hash != ExecutionBlockHash::zero())
                     {
                         // Spawn a new task to update the EE without waiting for it to complete.
                         let inner_chain = beacon_chain.clone();
@@ -1030,7 +1031,7 @@ where
 }
 
 impl<TSlotClock, TEth1Backend, E>
-    ClientBuilder<Witness<TSlotClock, TEth1Backend, E, LevelDB<E>, LevelDB<E>>>
+    ClientBuilder<Witness<TSlotClock, TEth1Backend, E, BeaconNodeBackend<E>, BeaconNodeBackend<E>>>
 where
     TSlotClock: SlotClock + 'static,
     TEth1Backend: Eth1ChainBackend<E> + 'static,
diff --git a/beacon_node/client/src/notifier.rs b/beacon_node/client/src/notifier.rs
index f686c2c650..0c3b1578d6 100644
--- a/beacon_node/client/src/notifier.rs
+++ b/beacon_node/client/src/notifier.rs
@@ -4,6 +4,7 @@ use beacon_chain::{
     capella_readiness::CapellaReadiness,
     deneb_readiness::DenebReadiness,
     electra_readiness::ElectraReadiness,
+    fulu_readiness::FuluReadiness,
     BeaconChain, BeaconChainTypes, ExecutionStatus,
 };
 use lighthouse_network::{types::SyncState, NetworkGlobals};
@@ -197,7 +198,7 @@ pub fn spawn_notifier<T: BeaconChainTypes>(
                 );
 
                 let speed = speedo.slots_per_second();
-                let display_speed = speed.map_or(false, |speed| speed != 0.0);
+                let display_speed = speed.is_some_and(|speed| speed != 0.0);
 
                 if display_speed {
                     info!(
@@ -233,7 +234,7 @@ pub fn spawn_notifier<T: BeaconChainTypes>(
                 );
 
                 let speed = speedo.slots_per_second();
-                let display_speed = speed.map_or(false, |speed| speed != 0.0);
+                let display_speed = speed.is_some_and(|speed| speed != 0.0);
 
                 if display_speed {
                     info!(
@@ -315,6 +316,7 @@ pub fn spawn_notifier<T: BeaconChainTypes>(
             capella_readiness_logging(current_slot, &beacon_chain, &log).await;
             deneb_readiness_logging(current_slot, &beacon_chain, &log).await;
             electra_readiness_logging(current_slot, &beacon_chain, &log).await;
+            fulu_readiness_logging(current_slot, &beacon_chain, &log).await;
         }
     };
 
@@ -339,9 +341,7 @@ async fn bellatrix_readiness_logging<T: BeaconChainTypes>(
         .message()
         .body()
         .execution_payload()
-        .map_or(false, |payload| {
-            payload.parent_hash() != ExecutionBlockHash::zero()
-        });
+        .is_ok_and(|payload| payload.parent_hash() != ExecutionBlockHash::zero());
 
     let has_execution_layer = beacon_chain.execution_layer.is_some();
 
@@ -588,6 +588,62 @@ async fn electra_readiness_logging<T: BeaconChainTypes>(
     }
 }
 
+/// Provides some helpful logging to users to indicate if their node is ready for Fulu.
+async fn fulu_readiness_logging<T: BeaconChainTypes>(
+    current_slot: Slot,
+    beacon_chain: &BeaconChain<T>,
+    log: &Logger,
+) {
+    let fulu_completed = beacon_chain
+        .canonical_head
+        .cached_head()
+        .snapshot
+        .beacon_state
+        .fork_name_unchecked()
+        .fulu_enabled();
+
+    let has_execution_layer = beacon_chain.execution_layer.is_some();
+
+    if fulu_completed && has_execution_layer
+        || !beacon_chain.is_time_to_prepare_for_fulu(current_slot)
+    {
+        return;
+    }
+
+    if fulu_completed && !has_execution_layer {
+        error!(
+            log,
+            "Execution endpoint required";
+            "info" => "you need a Fulu enabled execution engine to validate blocks."
+        );
+        return;
+    }
+
+    match beacon_chain.check_fulu_readiness().await {
+        FuluReadiness::Ready => {
+            info!(
+                log,
+                "Ready for Fulu";
+                "info" => "ensure the execution endpoint is updated to the latest Fulu release"
+            )
+        }
+        readiness @ FuluReadiness::ExchangeCapabilitiesFailed { error: _ } => {
+            error!(
+                log,
+                "Not ready for Fulu";
+                "hint" => "the execution endpoint may be offline",
+                "info" => %readiness,
+            )
+        }
+        readiness => warn!(
+            log,
+            "Not ready for Fulu";
+            "hint" => "try updating the execution endpoint",
+            "info" => %readiness,
+        ),
+    }
+}
+
 async fn genesis_execution_payload_logging<T: BeaconChainTypes>(
     beacon_chain: &BeaconChain<T>,
     log: &Logger,
diff --git a/beacon_node/execution_layer/src/engine_api.rs b/beacon_node/execution_layer/src/engine_api.rs
index df16a90305..8b8bc257c7 100644
--- a/beacon_node/execution_layer/src/engine_api.rs
+++ b/beacon_node/execution_layer/src/engine_api.rs
@@ -1,10 +1,10 @@
 use crate::engines::ForkchoiceState;
 use crate::http::{
     ENGINE_FORKCHOICE_UPDATED_V1, ENGINE_FORKCHOICE_UPDATED_V2, ENGINE_FORKCHOICE_UPDATED_V3,
-    ENGINE_GET_BLOBS_V1, ENGINE_GET_CLIENT_VERSION_V1, ENGINE_GET_INCLUSION_LIST_V1,
-    ENGINE_GET_PAYLOAD_BODIES_BY_HASH_V1, ENGINE_GET_PAYLOAD_BODIES_BY_RANGE_V1,
-    ENGINE_GET_PAYLOAD_V1, ENGINE_GET_PAYLOAD_V2, ENGINE_GET_PAYLOAD_V3, ENGINE_GET_PAYLOAD_V4,
-    ENGINE_NEW_PAYLOAD_V1, ENGINE_NEW_PAYLOAD_V2, ENGINE_NEW_PAYLOAD_V3, ENGINE_NEW_PAYLOAD_V4,
+    ENGINE_GET_BLOBS_V1, ENGINE_GET_CLIENT_VERSION_V1, ENGINE_GET_PAYLOAD_BODIES_BY_HASH_V1,
+    ENGINE_GET_PAYLOAD_BODIES_BY_RANGE_V1, ENGINE_GET_PAYLOAD_V1, ENGINE_GET_PAYLOAD_V2,
+    ENGINE_GET_PAYLOAD_V3, ENGINE_GET_PAYLOAD_V4, ENGINE_GET_PAYLOAD_V5, ENGINE_NEW_PAYLOAD_V1,
+    ENGINE_NEW_PAYLOAD_V2, ENGINE_NEW_PAYLOAD_V3, ENGINE_NEW_PAYLOAD_V4, ENGINE_NEW_PAYLOAD_V5, ENGINE_GET_INCLUSION_LIST_V1
 };
 use eth2::types::{
     BlobsBundle, SsePayloadAttributes, SsePayloadAttributesV1, SsePayloadAttributesV2,
@@ -24,7 +24,7 @@ pub use types::{
 };
 use types::{
     ExecutionPayloadBellatrix, ExecutionPayloadCapella, ExecutionPayloadDeneb,
-    ExecutionPayloadElectra, ExecutionRequests, KzgProofs,
+    ExecutionPayloadElectra, ExecutionPayloadFulu, ExecutionRequests, KzgProofs,
 };
 use types::{Graffiti, GRAFFITI_BYTES_LEN};
 
@@ -35,7 +35,7 @@ mod new_payload_request;
 
 pub use new_payload_request::{
     NewPayloadRequest, NewPayloadRequestBellatrix, NewPayloadRequestCapella,
-    NewPayloadRequestDeneb, NewPayloadRequestElectra,
+    NewPayloadRequestDeneb, NewPayloadRequestElectra, NewPayloadRequestFulu,
 };
 
 pub const LATEST_TAG: &str = "latest";
@@ -261,7 +261,7 @@ pub struct ProposeBlindedBlockResponse {
 }
 
 #[superstruct(
-    variants(Bellatrix, Capella, Deneb, Electra),
+    variants(Bellatrix, Capella, Deneb, Electra, Fulu),
     variant_attributes(derive(Clone, Debug, PartialEq),),
     map_into(ExecutionPayload),
     map_ref_into(ExecutionPayloadRef),
@@ -281,12 +281,14 @@ pub struct GetPayloadResponse<E: EthSpec> {
     pub execution_payload: ExecutionPayloadDeneb<E>,
     #[superstruct(only(Electra), partial_getter(rename = "execution_payload_electra"))]
     pub execution_payload: ExecutionPayloadElectra<E>,
+    #[superstruct(only(Fulu), partial_getter(rename = "execution_payload_fulu"))]
+    pub execution_payload: ExecutionPayloadFulu<E>,
     pub block_value: Uint256,
-    #[superstruct(only(Deneb, Electra))]
+    #[superstruct(only(Deneb, Electra, Fulu))]
     pub blobs_bundle: BlobsBundle<E>,
-    #[superstruct(only(Deneb, Electra), partial_getter(copy))]
+    #[superstruct(only(Deneb, Electra, Fulu), partial_getter(copy))]
     pub should_override_builder: bool,
-    #[superstruct(only(Electra))]
+    #[superstruct(only(Electra, Fulu))]
     pub requests: ExecutionRequests<E>,
 }
 
@@ -354,6 +356,12 @@ impl<E: EthSpec> From<GetPayloadResponse<E>>
                 Some(inner.blobs_bundle),
                 Some(inner.requests),
             ),
+            GetPayloadResponse::Fulu(inner) => (
+                ExecutionPayload::Fulu(inner.execution_payload),
+                inner.block_value,
+                Some(inner.blobs_bundle),
+                Some(inner.requests),
+            ),
         }
     }
 }
@@ -487,6 +495,34 @@ impl<E: EthSpec> ExecutionPayloadBodyV1<E> {
                     ))
                 }
             }
+            ExecutionPayloadHeader::Fulu(header) => {
+                if let Some(withdrawals) = self.withdrawals {
+                    Ok(ExecutionPayload::Fulu(ExecutionPayloadFulu {
+                        parent_hash: header.parent_hash,
+                        fee_recipient: header.fee_recipient,
+                        state_root: header.state_root,
+                        receipts_root: header.receipts_root,
+                        logs_bloom: header.logs_bloom,
+                        prev_randao: header.prev_randao,
+                        block_number: header.block_number,
+                        gas_limit: header.gas_limit,
+                        gas_used: header.gas_used,
+                        timestamp: header.timestamp,
+                        extra_data: header.extra_data,
+                        base_fee_per_gas: header.base_fee_per_gas,
+                        block_hash: header.block_hash,
+                        transactions: self.transactions,
+                        withdrawals,
+                        blob_gas_used: header.blob_gas_used,
+                        excess_blob_gas: header.excess_blob_gas,
+                    }))
+                } else {
+                    Err(format!(
+                        "block {} is post capella but payload body doesn't have withdrawals",
+                        header.block_hash
+                    ))
+                }
+            }
         }
     }
 }
@@ -497,6 +533,7 @@ pub struct EngineCapabilities {
     pub new_payload_v2: bool,
     pub new_payload_v3: bool,
     pub new_payload_v4: bool,
+    pub new_payload_v5: bool,
     pub forkchoice_updated_v1: bool,
     pub forkchoice_updated_v2: bool,
     pub forkchoice_updated_v3: bool,
@@ -506,6 +543,7 @@ pub struct EngineCapabilities {
     pub get_payload_v2: bool,
     pub get_payload_v3: bool,
     pub get_payload_v4: bool,
+    pub get_payload_v5: bool,
     pub get_client_version_v1: bool,
     pub get_blobs_v1: bool,
     pub get_inclusion_list_v1: bool,
@@ -526,6 +564,9 @@ impl EngineCapabilities {
         if self.new_payload_v4 {
             response.push(ENGINE_NEW_PAYLOAD_V4);
         }
+        if self.new_payload_v5 {
+            response.push(ENGINE_NEW_PAYLOAD_V5);
+        }
         if self.forkchoice_updated_v1 {
             response.push(ENGINE_FORKCHOICE_UPDATED_V1);
         }
@@ -553,6 +594,9 @@ impl EngineCapabilities {
         if self.get_payload_v4 {
             response.push(ENGINE_GET_PAYLOAD_V4);
         }
+        if self.get_payload_v5 {
+            response.push(ENGINE_GET_PAYLOAD_V5);
+        }
         if self.get_client_version_v1 {
             response.push(ENGINE_GET_CLIENT_VERSION_V1);
         }
diff --git a/beacon_node/execution_layer/src/engine_api/http.rs b/beacon_node/execution_layer/src/engine_api/http.rs
index 5d22be9afd..2d5716ea56 100644
--- a/beacon_node/execution_layer/src/engine_api/http.rs
+++ b/beacon_node/execution_layer/src/engine_api/http.rs
@@ -35,12 +35,14 @@ pub const ENGINE_NEW_PAYLOAD_V1: &str = "engine_newPayloadV1";
 pub const ENGINE_NEW_PAYLOAD_V2: &str = "engine_newPayloadV2";
 pub const ENGINE_NEW_PAYLOAD_V3: &str = "engine_newPayloadV3";
 pub const ENGINE_NEW_PAYLOAD_V4: &str = "engine_newPayloadV4";
+pub const ENGINE_NEW_PAYLOAD_V5: &str = "engine_newPayloadV5";
 pub const ENGINE_NEW_PAYLOAD_TIMEOUT: Duration = Duration::from_secs(8);
 
 pub const ENGINE_GET_PAYLOAD_V1: &str = "engine_getPayloadV1";
 pub const ENGINE_GET_PAYLOAD_V2: &str = "engine_getPayloadV2";
 pub const ENGINE_GET_PAYLOAD_V3: &str = "engine_getPayloadV3";
 pub const ENGINE_GET_PAYLOAD_V4: &str = "engine_getPayloadV4";
+pub const ENGINE_GET_PAYLOAD_V5: &str = "engine_getPayloadV5";
 pub const ENGINE_GET_PAYLOAD_TIMEOUT: Duration = Duration::from_secs(2);
 
 pub const ENGINE_FORKCHOICE_UPDATED_V1: &str = "engine_forkchoiceUpdatedV1";
@@ -75,10 +77,12 @@ pub static LIGHTHOUSE_CAPABILITIES: &[&str] = &[
     ENGINE_NEW_PAYLOAD_V2,
     ENGINE_NEW_PAYLOAD_V3,
     ENGINE_NEW_PAYLOAD_V4,
+    ENGINE_NEW_PAYLOAD_V5,
     ENGINE_GET_PAYLOAD_V1,
     ENGINE_GET_PAYLOAD_V2,
     ENGINE_GET_PAYLOAD_V3,
     ENGINE_GET_PAYLOAD_V4,
+    ENGINE_GET_PAYLOAD_V5,
     ENGINE_FORKCHOICE_UPDATED_V1,
     ENGINE_FORKCHOICE_UPDATED_V2,
     ENGINE_FORKCHOICE_UPDATED_V3,
@@ -162,9 +166,7 @@ pub mod deposit_log {
             };
 
             let signature_is_valid = deposit_pubkey_signature_message(&deposit_data, spec)
-                .map_or(false, |(public_key, signature, msg)| {
-                    signature.verify(&public_key, msg)
-                });
+                .is_some_and(|(public_key, signature, msg)| signature.verify(&public_key, msg));
 
             Ok(DepositLog {
                 deposit_data,
@@ -596,7 +598,7 @@ impl<T: Clone> CachedResponse<T> {
 
     /// returns `true` if the entry's age is >= age_limit
     pub fn older_than(&self, age_limit: Option<Duration>) -> bool {
-        age_limit.map_or(false, |limit| self.age() >= limit)
+        age_limit.is_some_and(|limit| self.age() >= limit)
     }
 }
 
@@ -743,9 +745,9 @@ impl HttpJsonRpc {
         .await
     }
 
-    pub async fn get_block_by_number<'a>(
+    pub async fn get_block_by_number(
         &self,
-        query: BlockByNumberQuery<'a>,
+        query: BlockByNumberQuery<'_>,
     ) -> Result<Option<ExecutionBlock>, Error> {
         let params = json!([query, RETURN_FULL_TRANSACTION_OBJECTS]);
 
@@ -850,6 +852,31 @@ impl HttpJsonRpc {
         Ok(response.into())
     }
 
+    // TODO(fulu): switch to v5 endpoint when the EL is ready for Fulu
+    pub async fn new_payload_v4_fulu<E: EthSpec>(
+        &self,
+        new_payload_request_fulu: NewPayloadRequestFulu<'_, E>,
+    ) -> Result<PayloadStatusV1, Error> {
+        let params = json!([
+            JsonExecutionPayload::V5(new_payload_request_fulu.execution_payload.clone().into()),
+            new_payload_request_fulu.versioned_hashes,
+            new_payload_request_fulu.parent_beacon_block_root,
+            new_payload_request_fulu
+                .execution_requests
+                .get_execution_requests_list(),
+        ]);
+
+        let response: JsonPayloadStatusV1 = self
+            .rpc_request(
+                ENGINE_NEW_PAYLOAD_V4,
+                params,
+                ENGINE_NEW_PAYLOAD_TIMEOUT * self.execution_timeout_multiplier,
+            )
+            .await?;
+
+        Ok(response.into())
+    }
+
     pub async fn get_payload_v1<E: EthSpec>(
         &self,
         payload_id: PayloadId,
@@ -905,9 +932,10 @@ impl HttpJsonRpc {
                     .try_into()
                     .map_err(Error::BadResponse)
             }
-            ForkName::Base | ForkName::Altair | ForkName::Deneb | ForkName::Electra => Err(
-                Error::UnsupportedForkVariant(format!("called get_payload_v2 with {}", fork_name)),
-            ),
+            _ => Err(Error::UnsupportedForkVariant(format!(
+                "called get_payload_v2 with {}",
+                fork_name
+            ))),
         }
     }
 
@@ -931,11 +959,7 @@ impl HttpJsonRpc {
                     .try_into()
                     .map_err(Error::BadResponse)
             }
-            ForkName::Base
-            | ForkName::Altair
-            | ForkName::Bellatrix
-            | ForkName::Capella
-            | ForkName::Electra => Err(Error::UnsupportedForkVariant(format!(
+            _ => Err(Error::UnsupportedForkVariant(format!(
                 "called get_payload_v3 with {}",
                 fork_name
             ))),
@@ -962,17 +986,53 @@ impl HttpJsonRpc {
                     .try_into()
                     .map_err(Error::BadResponse)
             }
-            ForkName::Base
-            | ForkName::Altair
-            | ForkName::Bellatrix
-            | ForkName::Capella
-            | ForkName::Deneb => Err(Error::UnsupportedForkVariant(format!(
+            // TODO(fulu): remove when v5 method is ready.
+            ForkName::Fulu => {
+                let response: JsonGetPayloadResponseV5<E> = self
+                    .rpc_request(
+                        ENGINE_GET_PAYLOAD_V4,
+                        params,
+                        ENGINE_GET_PAYLOAD_TIMEOUT * self.execution_timeout_multiplier,
+                    )
+                    .await?;
+                JsonGetPayloadResponse::V5(response)
+                    .try_into()
+                    .map_err(Error::BadResponse)
+            }
+            _ => Err(Error::UnsupportedForkVariant(format!(
                 "called get_payload_v4 with {}",
                 fork_name
             ))),
         }
     }
 
+    pub async fn get_payload_v5<E: EthSpec>(
+        &self,
+        fork_name: ForkName,
+        payload_id: PayloadId,
+    ) -> Result<GetPayloadResponse<E>, Error> {
+        let params = json!([JsonPayloadIdRequest::from(payload_id)]);
+
+        match fork_name {
+            ForkName::Fulu => {
+                let response: JsonGetPayloadResponseV5<E> = self
+                    .rpc_request(
+                        ENGINE_GET_PAYLOAD_V5,
+                        params,
+                        ENGINE_GET_PAYLOAD_TIMEOUT * self.execution_timeout_multiplier,
+                    )
+                    .await?;
+                JsonGetPayloadResponse::V5(response)
+                    .try_into()
+                    .map_err(Error::BadResponse)
+            }
+            _ => Err(Error::UnsupportedForkVariant(format!(
+                "called get_payload_v5 with {}",
+                fork_name
+            ))),
+        }
+    }
+
     pub async fn forkchoice_updated_v1(
         &self,
         forkchoice_state: ForkchoiceState,
@@ -1096,6 +1156,7 @@ impl HttpJsonRpc {
             new_payload_v2: capabilities.contains(ENGINE_NEW_PAYLOAD_V2),
             new_payload_v3: capabilities.contains(ENGINE_NEW_PAYLOAD_V3),
             new_payload_v4: capabilities.contains(ENGINE_NEW_PAYLOAD_V4),
+            new_payload_v5: capabilities.contains(ENGINE_NEW_PAYLOAD_V5),
             forkchoice_updated_v1: capabilities.contains(ENGINE_FORKCHOICE_UPDATED_V1),
             forkchoice_updated_v2: capabilities.contains(ENGINE_FORKCHOICE_UPDATED_V2),
             forkchoice_updated_v3: capabilities.contains(ENGINE_FORKCHOICE_UPDATED_V3),
@@ -1107,6 +1168,7 @@ impl HttpJsonRpc {
             get_payload_v2: capabilities.contains(ENGINE_GET_PAYLOAD_V2),
             get_payload_v3: capabilities.contains(ENGINE_GET_PAYLOAD_V3),
             get_payload_v4: capabilities.contains(ENGINE_GET_PAYLOAD_V4),
+            get_payload_v5: capabilities.contains(ENGINE_GET_PAYLOAD_V5),
             get_client_version_v1: capabilities.contains(ENGINE_GET_CLIENT_VERSION_V1),
             get_blobs_v1: capabilities.contains(ENGINE_GET_BLOBS_V1),
             get_inclusion_list_v1: capabilities.contains(ENGINE_GET_INCLUSION_LIST_V1),
@@ -1238,6 +1300,14 @@ impl HttpJsonRpc {
                     Err(Error::RequiredMethodUnsupported("engine_newPayloadV4"))
                 }
             }
+            NewPayloadRequest::Fulu(new_payload_request_fulu) => {
+                // TODO(fulu): switch to v5 endpoint when the EL is ready for Fulu
+                if engine_capabilities.new_payload_v4 {
+                    self.new_payload_v4_fulu(new_payload_request_fulu).await
+                } else {
+                    Err(Error::RequiredMethodUnsupported("engine_newPayloadV4"))
+                }
+            }
         }
     }
 
@@ -1273,6 +1343,14 @@ impl HttpJsonRpc {
                     Err(Error::RequiredMethodUnsupported("engine_getPayloadv4"))
                 }
             }
+            ForkName::Fulu => {
+                // TODO(fulu): switch to v5 when the EL is ready
+                if engine_capabilities.get_payload_v4 {
+                    self.get_payload_v4(fork_name, payload_id).await
+                } else {
+                    Err(Error::RequiredMethodUnsupported("engine_getPayloadv5"))
+                }
+            }
             ForkName::Base | ForkName::Altair => Err(Error::UnsupportedForkVariant(format!(
                 "called get_payload with {}",
                 fork_name
@@ -1345,7 +1423,8 @@ mod test {
 
     impl Tester {
         pub fn new(with_auth: bool) -> Self {
-            let server = MockServer::unit_testing();
+            let spec = Arc::new(MainnetEthSpec::default_spec());
+            let server = MockServer::unit_testing(spec);
 
             let rpc_url = SensitiveUrl::parse(&server.url()).unwrap();
             let echo_url = SensitiveUrl::parse(&format!("{}/echo", server.url())).unwrap();
diff --git a/beacon_node/execution_layer/src/engine_api/json_structures.rs b/beacon_node/execution_layer/src/engine_api/json_structures.rs
index 1c6639804e..96615297d8 100644
--- a/beacon_node/execution_layer/src/engine_api/json_structures.rs
+++ b/beacon_node/execution_layer/src/engine_api/json_structures.rs
@@ -7,7 +7,7 @@ use superstruct::superstruct;
 use types::beacon_block_body::KzgCommitments;
 use types::blob_sidecar::BlobsList;
 use types::execution_requests::{
-    ConsolidationRequests, DepositRequests, RequestPrefix, WithdrawalRequests,
+    ConsolidationRequests, DepositRequests, RequestType, WithdrawalRequests,
 };
 use types::{Blob, FixedVector, KzgProof, Unsigned};
 
@@ -65,7 +65,7 @@ pub struct JsonPayloadIdResponse {
 }
 
 #[superstruct(
-    variants(V1, V2, V3, V4),
+    variants(V1, V2, V3, V4, V5),
     variant_attributes(
         derive(Debug, PartialEq, Default, Serialize, Deserialize,),
         serde(bound = "E: EthSpec", rename_all = "camelCase"),
@@ -100,12 +100,12 @@ pub struct JsonExecutionPayload<E: EthSpec> {
     pub block_hash: ExecutionBlockHash,
     #[serde(with = "ssz_types::serde_utils::list_of_hex_var_list")]
     pub transactions: Transactions<E>,
-    #[superstruct(only(V2, V3, V4))]
+    #[superstruct(only(V2, V3, V4, V5))]
     pub withdrawals: VariableList<JsonWithdrawal, E::MaxWithdrawalsPerPayload>,
-    #[superstruct(only(V3, V4))]
+    #[superstruct(only(V3, V4, V5))]
     #[serde(with = "serde_utils::u64_hex_be")]
     pub blob_gas_used: u64,
-    #[superstruct(only(V3, V4))]
+    #[superstruct(only(V3, V4, V5))]
     #[serde(with = "serde_utils::u64_hex_be")]
     pub excess_blob_gas: u64,
 }
@@ -214,6 +214,35 @@ impl<E: EthSpec> From<ExecutionPayloadElectra<E>> for JsonExecutionPayloadV4<E>
     }
 }
 
+impl<E: EthSpec> From<ExecutionPayloadFulu<E>> for JsonExecutionPayloadV5<E> {
+    fn from(payload: ExecutionPayloadFulu<E>) -> Self {
+        JsonExecutionPayloadV5 {
+            parent_hash: payload.parent_hash,
+            fee_recipient: payload.fee_recipient,
+            state_root: payload.state_root,
+            receipts_root: payload.receipts_root,
+            logs_bloom: payload.logs_bloom,
+            prev_randao: payload.prev_randao,
+            block_number: payload.block_number,
+            gas_limit: payload.gas_limit,
+            gas_used: payload.gas_used,
+            timestamp: payload.timestamp,
+            extra_data: payload.extra_data,
+            base_fee_per_gas: payload.base_fee_per_gas,
+            block_hash: payload.block_hash,
+            transactions: payload.transactions,
+            withdrawals: payload
+                .withdrawals
+                .into_iter()
+                .map(Into::into)
+                .collect::<Vec<_>>()
+                .into(),
+            blob_gas_used: payload.blob_gas_used,
+            excess_blob_gas: payload.excess_blob_gas,
+        }
+    }
+}
+
 impl<E: EthSpec> From<ExecutionPayload<E>> for JsonExecutionPayload<E> {
     fn from(execution_payload: ExecutionPayload<E>) -> Self {
         match execution_payload {
@@ -221,6 +250,7 @@ impl<E: EthSpec> From<ExecutionPayload<E>> for JsonExecutionPayload<E> {
             ExecutionPayload::Capella(payload) => JsonExecutionPayload::V2(payload.into()),
             ExecutionPayload::Deneb(payload) => JsonExecutionPayload::V3(payload.into()),
             ExecutionPayload::Electra(payload) => JsonExecutionPayload::V4(payload.into()),
+            ExecutionPayload::Fulu(payload) => JsonExecutionPayload::V5(payload.into()),
         }
     }
 }
@@ -330,6 +360,35 @@ impl<E: EthSpec> From<JsonExecutionPayloadV4<E>> for ExecutionPayloadElectra<E>
     }
 }
 
+impl<E: EthSpec> From<JsonExecutionPayloadV5<E>> for ExecutionPayloadFulu<E> {
+    fn from(payload: JsonExecutionPayloadV5<E>) -> Self {
+        ExecutionPayloadFulu {
+            parent_hash: payload.parent_hash,
+            fee_recipient: payload.fee_recipient,
+            state_root: payload.state_root,
+            receipts_root: payload.receipts_root,
+            logs_bloom: payload.logs_bloom,
+            prev_randao: payload.prev_randao,
+            block_number: payload.block_number,
+            gas_limit: payload.gas_limit,
+            gas_used: payload.gas_used,
+            timestamp: payload.timestamp,
+            extra_data: payload.extra_data,
+            base_fee_per_gas: payload.base_fee_per_gas,
+            block_hash: payload.block_hash,
+            transactions: payload.transactions,
+            withdrawals: payload
+                .withdrawals
+                .into_iter()
+                .map(Into::into)
+                .collect::<Vec<_>>()
+                .into(),
+            blob_gas_used: payload.blob_gas_used,
+            excess_blob_gas: payload.excess_blob_gas,
+        }
+    }
+}
+
 impl<E: EthSpec> From<JsonExecutionPayload<E>> for ExecutionPayload<E> {
     fn from(json_execution_payload: JsonExecutionPayload<E>) -> Self {
         match json_execution_payload {
@@ -337,51 +396,85 @@ impl<E: EthSpec> From<JsonExecutionPayload<E>> for ExecutionPayload<E> {
             JsonExecutionPayload::V2(payload) => ExecutionPayload::Capella(payload.into()),
             JsonExecutionPayload::V3(payload) => ExecutionPayload::Deneb(payload.into()),
             JsonExecutionPayload::V4(payload) => ExecutionPayload::Electra(payload.into()),
+            JsonExecutionPayload::V5(payload) => ExecutionPayload::Fulu(payload.into()),
         }
     }
 }
 
+#[derive(Debug, Clone)]
+pub enum RequestsError {
+    InvalidHex(hex::FromHexError),
+    EmptyRequest(usize),
+    InvalidOrdering,
+    InvalidPrefix(u8),
+    DecodeError(String),
+}
+
 /// Format of `ExecutionRequests` received over the engine api.
 ///
-/// Array of ssz-encoded requests list encoded as hex bytes.
-/// The prefix of the request type is used to index into the array.
-///
-/// For e.g. [0xab, 0xcd, 0xef]
-/// Here, 0xab are the deposits bytes (prefix and index == 0)
-/// 0xcd are the withdrawals bytes (prefix and index == 1)
-/// 0xef are the consolidations bytes (prefix and index == 2)
+/// Array of ssz-encoded requests list encoded as hex bytes prefixed
+/// with a `RequestType`
 #[derive(Debug, Default, Clone, PartialEq, Serialize, Deserialize)]
 #[serde(transparent)]
 pub struct JsonExecutionRequests(pub Vec<String>);
 
 impl<E: EthSpec> TryFrom<JsonExecutionRequests> for ExecutionRequests<E> {
-    type Error = String;
+    type Error = RequestsError;
 
     fn try_from(value: JsonExecutionRequests) -> Result<Self, Self::Error> {
         let mut requests = ExecutionRequests::default();
-
+        let mut prev_prefix: Option<RequestType> = None;
         for (i, request) in value.0.into_iter().enumerate() {
             // hex string
             let decoded_bytes = hex::decode(request.strip_prefix("0x").unwrap_or(&request))
-                .map_err(|e| format!("Invalid hex {:?}", e))?;
-            match RequestPrefix::from_prefix(i as u8) {
-                Some(RequestPrefix::Deposit) => {
-                    requests.deposits = DepositRequests::<E>::from_ssz_bytes(&decoded_bytes)
-                        .map_err(|e| format!("Failed to decode DepositRequest from EL: {:?}", e))?;
+                .map_err(RequestsError::InvalidHex)?;
+
+            // The first byte of each element is the `request_type` and the remaining bytes are the `request_data`.
+            // Elements with empty `request_data` **MUST** be excluded from the list.
+            let Some((prefix_byte, request_bytes)) = decoded_bytes.split_first() else {
+                return Err(RequestsError::EmptyRequest(i));
+            };
+            if request_bytes.is_empty() {
+                return Err(RequestsError::EmptyRequest(i));
+            }
+            // Elements of the list **MUST** be ordered by `request_type` in ascending order
+            let current_prefix = RequestType::from_u8(*prefix_byte)
+                .ok_or(RequestsError::InvalidPrefix(*prefix_byte))?;
+            if let Some(prev) = prev_prefix {
+                if prev.to_u8() >= current_prefix.to_u8() {
+                    return Err(RequestsError::InvalidOrdering);
                 }
-                Some(RequestPrefix::Withdrawal) => {
-                    requests.withdrawals = WithdrawalRequests::<E>::from_ssz_bytes(&decoded_bytes)
+            }
+            prev_prefix = Some(current_prefix);
+
+            match current_prefix {
+                RequestType::Deposit => {
+                    requests.deposits = DepositRequests::<E>::from_ssz_bytes(request_bytes)
                         .map_err(|e| {
-                            format!("Failed to decode WithdrawalRequest from EL: {:?}", e)
+                            RequestsError::DecodeError(format!(
+                                "Failed to decode DepositRequest from EL: {:?}",
+                                e
+                            ))
                         })?;
                 }
-                Some(RequestPrefix::Consolidation) => {
-                    requests.consolidations =
-                        ConsolidationRequests::<E>::from_ssz_bytes(&decoded_bytes).map_err(
-                            |e| format!("Failed to decode ConsolidationRequest from EL: {:?}", e),
-                        )?;
+                RequestType::Withdrawal => {
+                    requests.withdrawals = WithdrawalRequests::<E>::from_ssz_bytes(request_bytes)
+                        .map_err(|e| {
+                        RequestsError::DecodeError(format!(
+                            "Failed to decode WithdrawalRequest from EL: {:?}",
+                            e
+                        ))
+                    })?;
+                }
+                RequestType::Consolidation => {
+                    requests.consolidations =
+                        ConsolidationRequests::<E>::from_ssz_bytes(request_bytes).map_err(|e| {
+                            RequestsError::DecodeError(format!(
+                                "Failed to decode ConsolidationRequest from EL: {:?}",
+                                e
+                            ))
+                        })?;
                 }
-                None => return Err("Empty requests string".to_string()),
             }
         }
         Ok(requests)
@@ -389,7 +482,7 @@ impl<E: EthSpec> TryFrom<JsonExecutionRequests> for ExecutionRequests<E> {
 }
 
 #[superstruct(
-    variants(V1, V2, V3, V4),
+    variants(V1, V2, V3, V4, V5),
     variant_attributes(
         derive(Debug, PartialEq, Serialize, Deserialize),
         serde(bound = "E: EthSpec", rename_all = "camelCase")
@@ -408,13 +501,15 @@ pub struct JsonGetPayloadResponse<E: EthSpec> {
     pub execution_payload: JsonExecutionPayloadV3<E>,
     #[superstruct(only(V4), partial_getter(rename = "execution_payload_v4"))]
     pub execution_payload: JsonExecutionPayloadV4<E>,
+    #[superstruct(only(V5), partial_getter(rename = "execution_payload_v5"))]
+    pub execution_payload: JsonExecutionPayloadV5<E>,
     #[serde(with = "serde_utils::u256_hex_be")]
     pub block_value: Uint256,
-    #[superstruct(only(V3, V4))]
+    #[superstruct(only(V3, V4, V5))]
     pub blobs_bundle: JsonBlobsBundleV1<E>,
-    #[superstruct(only(V3, V4))]
+    #[superstruct(only(V3, V4, V5))]
     pub should_override_builder: bool,
-    #[superstruct(only(V4))]
+    #[superstruct(only(V4, V5))]
     pub execution_requests: JsonExecutionRequests,
 }
 
@@ -448,7 +543,20 @@ impl<E: EthSpec> TryFrom<JsonGetPayloadResponse<E>> for GetPayloadResponse<E> {
                     block_value: response.block_value,
                     blobs_bundle: response.blobs_bundle.into(),
                     should_override_builder: response.should_override_builder,
-                    requests: response.execution_requests.try_into()?,
+                    requests: response.execution_requests.try_into().map_err(|e| {
+                        format!("Failed to convert json to execution requests : {:?}", e)
+                    })?,
+                }))
+            }
+            JsonGetPayloadResponse::V5(response) => {
+                Ok(GetPayloadResponse::Fulu(GetPayloadResponseFulu {
+                    execution_payload: response.execution_payload.into(),
+                    block_value: response.block_value,
+                    blobs_bundle: response.blobs_bundle.into(),
+                    should_override_builder: response.should_override_builder,
+                    requests: response.execution_requests.try_into().map_err(|e| {
+                        format!("Failed to convert json to execution requests  {:?}", e)
+                    })?,
                 }))
             }
         }
@@ -883,3 +991,154 @@ impl TryFrom<JsonClientVersionV1> for ClientVersionV1 {
         })
     }
 }
+
+#[cfg(test)]
+mod tests {
+    use ssz::Encode;
+    use types::{
+        ConsolidationRequest, DepositRequest, MainnetEthSpec, PublicKeyBytes, RequestType,
+        SignatureBytes, WithdrawalRequest,
+    };
+
+    use super::*;
+
+    fn create_request_string<T: Encode>(prefix: u8, request_bytes: &T) -> String {
+        format!(
+            "0x{:02x}{}",
+            prefix,
+            hex::encode(request_bytes.as_ssz_bytes())
+        )
+    }
+
+    /// Tests all error conditions except ssz decoding errors
+    ///
+    /// ***
+    /// Elements of the list MUST be ordered by request_type in ascending order.
+    /// Elements with empty request_data MUST be excluded from the list.
+    /// If any element is out of order, has a length of 1-byte or shorter,
+    /// or more than one element has the same type byte, client software MUST return -32602: Invalid params error.
+    /// ***
+    #[test]
+    fn test_invalid_execution_requests() {
+        let deposit_request = DepositRequest {
+            pubkey: PublicKeyBytes::empty(),
+            withdrawal_credentials: Hash256::random(),
+            amount: 32,
+            signature: SignatureBytes::empty(),
+            index: 0,
+        };
+
+        let consolidation_request = ConsolidationRequest {
+            source_address: Address::random(),
+            source_pubkey: PublicKeyBytes::empty(),
+            target_pubkey: PublicKeyBytes::empty(),
+        };
+
+        let withdrawal_request = WithdrawalRequest {
+            amount: 32,
+            source_address: Address::random(),
+            validator_pubkey: PublicKeyBytes::empty(),
+        };
+
+        // First check a valid request with all requests
+        assert!(
+            ExecutionRequests::<MainnetEthSpec>::try_from(JsonExecutionRequests(vec![
+                create_request_string(RequestType::Deposit.to_u8(), &deposit_request),
+                create_request_string(RequestType::Withdrawal.to_u8(), &withdrawal_request),
+                create_request_string(RequestType::Consolidation.to_u8(), &consolidation_request),
+            ]))
+            .is_ok()
+        );
+
+        // Single requests
+        assert!(
+            ExecutionRequests::<MainnetEthSpec>::try_from(JsonExecutionRequests(vec![
+                create_request_string(RequestType::Deposit.to_u8(), &deposit_request),
+            ]))
+            .is_ok()
+        );
+
+        assert!(
+            ExecutionRequests::<MainnetEthSpec>::try_from(JsonExecutionRequests(vec![
+                create_request_string(RequestType::Withdrawal.to_u8(), &withdrawal_request),
+            ]))
+            .is_ok()
+        );
+
+        assert!(
+            ExecutionRequests::<MainnetEthSpec>::try_from(JsonExecutionRequests(vec![
+                create_request_string(RequestType::Consolidation.to_u8(), &consolidation_request),
+            ]))
+            .is_ok()
+        );
+
+        // Out of order
+        assert!(matches!(
+            ExecutionRequests::<MainnetEthSpec>::try_from(JsonExecutionRequests(vec![
+                create_request_string(RequestType::Withdrawal.to_u8(), &withdrawal_request),
+                create_request_string(RequestType::Deposit.to_u8(), &deposit_request),
+            ]))
+            .unwrap_err(),
+            RequestsError::InvalidOrdering
+        ));
+
+        assert!(matches!(
+            ExecutionRequests::<MainnetEthSpec>::try_from(JsonExecutionRequests(vec![
+                create_request_string(RequestType::Consolidation.to_u8(), &consolidation_request),
+                create_request_string(RequestType::Withdrawal.to_u8(), &withdrawal_request),
+            ]))
+            .unwrap_err(),
+            RequestsError::InvalidOrdering
+        ));
+
+        assert!(matches!(
+            ExecutionRequests::<MainnetEthSpec>::try_from(JsonExecutionRequests(vec![
+                create_request_string(RequestType::Consolidation.to_u8(), &consolidation_request),
+                create_request_string(RequestType::Deposit.to_u8(), &deposit_request),
+            ]))
+            .unwrap_err(),
+            RequestsError::InvalidOrdering
+        ));
+
+        // Multiple requests of same type
+        assert!(matches!(
+            ExecutionRequests::<MainnetEthSpec>::try_from(JsonExecutionRequests(vec![
+                create_request_string(RequestType::Deposit.to_u8(), &deposit_request),
+                create_request_string(RequestType::Deposit.to_u8(), &deposit_request),
+            ]))
+            .unwrap_err(),
+            RequestsError::InvalidOrdering
+        ));
+
+        // Invalid prefix
+        assert!(matches!(
+            ExecutionRequests::<MainnetEthSpec>::try_from(JsonExecutionRequests(vec![
+                create_request_string(42, &deposit_request),
+            ]))
+            .unwrap_err(),
+            RequestsError::InvalidPrefix(42)
+        ));
+
+        // Prefix followed by no data
+        assert!(matches!(
+            ExecutionRequests::<MainnetEthSpec>::try_from(JsonExecutionRequests(vec![
+                create_request_string(RequestType::Deposit.to_u8(), &deposit_request),
+                create_request_string(
+                    RequestType::Consolidation.to_u8(),
+                    &Vec::<ConsolidationRequest>::new()
+                ),
+            ]))
+            .unwrap_err(),
+            RequestsError::EmptyRequest(1)
+        ));
+        // Empty request
+        assert!(matches!(
+            ExecutionRequests::<MainnetEthSpec>::try_from(JsonExecutionRequests(vec![
+                create_request_string(RequestType::Deposit.to_u8(), &deposit_request),
+                "0x".to_string()
+            ]))
+            .unwrap_err(),
+            RequestsError::EmptyRequest(1)
+        ));
+    }
+}
diff --git a/beacon_node/execution_layer/src/engine_api/new_payload_request.rs b/beacon_node/execution_layer/src/engine_api/new_payload_request.rs
index b3dc84d253..e3c2215463 100644
--- a/beacon_node/execution_layer/src/engine_api/new_payload_request.rs
+++ b/beacon_node/execution_layer/src/engine_api/new_payload_request.rs
@@ -9,11 +9,11 @@ use types::{
 };
 use types::{
     ExecutionPayloadBellatrix, ExecutionPayloadCapella, ExecutionPayloadDeneb,
-    ExecutionPayloadElectra, ExecutionRequests,
+    ExecutionPayloadElectra, ExecutionPayloadFulu, ExecutionRequests,
 };
 
 #[superstruct(
-    variants(Bellatrix, Capella, Deneb, Electra),
+    variants(Bellatrix, Capella, Deneb, Electra, Fulu),
     variant_attributes(derive(Clone, Debug, PartialEq),),
     map_into(ExecutionPayload),
     map_ref_into(ExecutionPayloadRef),
@@ -39,13 +39,15 @@ pub struct NewPayloadRequest<'block, E: EthSpec> {
     pub execution_payload: &'block ExecutionPayloadDeneb<E>,
     #[superstruct(only(Electra), partial_getter(rename = "execution_payload_electra"))]
     pub execution_payload: &'block ExecutionPayloadElectra<E>,
-    #[superstruct(only(Deneb, Electra))]
+    #[superstruct(only(Fulu), partial_getter(rename = "execution_payload_fulu"))]
+    pub execution_payload: &'block ExecutionPayloadFulu<E>,
+    #[superstruct(only(Deneb, Electra, Fulu))]
     pub versioned_hashes: Vec<VersionedHash>,
-    #[superstruct(only(Deneb, Electra))]
+    #[superstruct(only(Deneb, Electra, Fulu))]
     pub parent_beacon_block_root: Hash256,
-    #[superstruct(only(Electra))]
+    #[superstruct(only(Electra, Fulu))]
     pub execution_requests: &'block ExecutionRequests<E>,
-    #[superstruct(only(Electra))]
+    #[superstruct(only(Electra, Fulu))]
     pub il_transactions: InclusionListTransactions<E>,
 }
 
@@ -56,6 +58,7 @@ impl<'block, E: EthSpec> NewPayloadRequest<'block, E> {
             Self::Capella(payload) => payload.execution_payload.parent_hash,
             Self::Deneb(payload) => payload.execution_payload.parent_hash,
             Self::Electra(payload) => payload.execution_payload.parent_hash,
+            Self::Fulu(payload) => payload.execution_payload.parent_hash,
         }
     }
 
@@ -65,6 +68,7 @@ impl<'block, E: EthSpec> NewPayloadRequest<'block, E> {
             Self::Capella(payload) => payload.execution_payload.block_hash,
             Self::Deneb(payload) => payload.execution_payload.block_hash,
             Self::Electra(payload) => payload.execution_payload.block_hash,
+            Self::Fulu(payload) => payload.execution_payload.block_hash,
         }
     }
 
@@ -74,6 +78,7 @@ impl<'block, E: EthSpec> NewPayloadRequest<'block, E> {
             Self::Capella(payload) => payload.execution_payload.block_number,
             Self::Deneb(payload) => payload.execution_payload.block_number,
             Self::Electra(payload) => payload.execution_payload.block_number,
+            Self::Fulu(payload) => payload.execution_payload.block_number,
         }
     }
 
@@ -83,6 +88,7 @@ impl<'block, E: EthSpec> NewPayloadRequest<'block, E> {
             Self::Capella(request) => ExecutionPayloadRef::Capella(request.execution_payload),
             Self::Deneb(request) => ExecutionPayloadRef::Deneb(request.execution_payload),
             Self::Electra(request) => ExecutionPayloadRef::Electra(request.execution_payload),
+            Self::Fulu(request) => ExecutionPayloadRef::Fulu(request.execution_payload),
         }
     }
 
@@ -94,6 +100,7 @@ impl<'block, E: EthSpec> NewPayloadRequest<'block, E> {
             Self::Capella(request) => ExecutionPayload::Capella(request.execution_payload.clone()),
             Self::Deneb(request) => ExecutionPayload::Deneb(request.execution_payload.clone()),
             Self::Electra(request) => ExecutionPayload::Electra(request.execution_payload.clone()),
+            Self::Fulu(request) => ExecutionPayload::Fulu(request.execution_payload.clone()),
         }
     }
 
@@ -123,6 +130,11 @@ impl<'block, E: EthSpec> NewPayloadRequest<'block, E> {
 
         let _timer = metrics::start_timer(&metrics::EXECUTION_LAYER_VERIFY_BLOCK_HASH);
 
+        // Check that no transactions in the payload are zero length
+        if payload.transactions().iter().any(|slice| slice.is_empty()) {
+            return Err(Error::ZeroLengthTransaction);
+        }
+
         let (header_hash, rlp_transactions_root) = calculate_execution_block_hash(
             payload,
             parent_beacon_block_root,
@@ -194,6 +206,18 @@ impl<'a, E: EthSpec> NewPayloadRequest<'a, E> {
                 execution_requests: &block_ref.body.execution_requests,
                 il_transactions,
             })),
+            BeaconBlockRef::Fulu(block_ref) => Ok(Self::Fulu(NewPayloadRequestFulu {
+                execution_payload: &block_ref.body.execution_payload.execution_payload,
+                versioned_hashes: block_ref
+                    .body
+                    .blob_kzg_commitments
+                    .iter()
+                    .map(kzg_commitment_to_versioned_hash)
+                    .collect(),
+                parent_beacon_block_root: block_ref.parent_root,
+                execution_requests: &block_ref.body.execution_requests,
+                il_transactions,
+            })),
         }
     }
 }
@@ -237,6 +261,18 @@ impl<'a, E: EthSpec> TryFrom<BeaconBlockRef<'a, E>> for NewPayloadRequest<'a, E>
                 execution_requests: &block_ref.body.execution_requests,
                 il_transactions: vec![].into(),
             })),
+            BeaconBlockRef::Fulu(block_ref) => Ok(Self::Fulu(NewPayloadRequestFulu {
+                execution_payload: &block_ref.body.execution_payload.execution_payload,
+                versioned_hashes: block_ref
+                    .body
+                    .blob_kzg_commitments
+                    .iter()
+                    .map(kzg_commitment_to_versioned_hash)
+                    .collect(),
+                parent_beacon_block_root: block_ref.parent_root,
+                execution_requests: &block_ref.body.execution_requests,
+                il_transactions: vec![].into()
+            })),
         }
     }
 }
@@ -256,6 +292,7 @@ impl<'a, E: EthSpec> TryFrom<ExecutionPayloadRef<'a, E>> for NewPayloadRequest<'
             })),
             ExecutionPayloadRef::Deneb(_) => Err(Self::Error::IncorrectStateVariant),
             ExecutionPayloadRef::Electra(_) => Err(Self::Error::IncorrectStateVariant),
+            ExecutionPayloadRef::Fulu(_) => Err(Self::Error::IncorrectStateVariant),
         }
     }
 }
diff --git a/beacon_node/execution_layer/src/lib.rs b/beacon_node/execution_layer/src/lib.rs
index 41f5baa67b..9ea172689d 100644
--- a/beacon_node/execution_layer/src/lib.rs
+++ b/beacon_node/execution_layer/src/lib.rs
@@ -54,8 +54,8 @@ use types::{
 };
 use types::{
     BeaconStateError, BlindedPayload, ChainSpec, Epoch, ExecPayload, ExecutionPayloadBellatrix,
-    ExecutionPayloadCapella, ExecutionPayloadElectra, FullPayload, InclusionListTransactions,
-    ProposerPreparationData, PublicKeyBytes, Signature, Slot,
+    ExecutionPayloadCapella, ExecutionPayloadElectra, ExecutionPayloadFulu, FullPayload,
+    ProposerPreparationData, PublicKeyBytes, Signature, Slot, InclusionListTransactions
 };
 
 mod block_hash;
@@ -121,7 +121,14 @@ impl<E: EthSpec> TryFrom<BuilderBid<E>> for ProvenancedPayload<BlockProposalCont
                 block_value: builder_bid.value,
                 kzg_commitments: builder_bid.blob_kzg_commitments,
                 blobs_and_proofs: None,
-                // TODO(electra): update this with builder api returning the requests
+                requests: Some(builder_bid.execution_requests),
+            },
+            BuilderBid::Fulu(builder_bid) => BlockProposalContents::PayloadAndBlobs {
+                payload: ExecutionPayloadHeader::Fulu(builder_bid.header).into(),
+                block_value: builder_bid.value,
+                kzg_commitments: builder_bid.blob_kzg_commitments,
+                blobs_and_proofs: None,
+                // TODO(fulu): update this with builder api returning the requests
                 requests: None,
             },
         };
@@ -149,6 +156,7 @@ pub enum Error {
         payload: ExecutionBlockHash,
         transactions_root: Hash256,
     },
+    ZeroLengthTransaction,
     PayloadBodiesByRangeNotSupported,
     InvalidJWTSecret(String),
     InvalidForkForPayload,
@@ -321,7 +329,7 @@ impl<E: EthSpec, Payload: AbstractExecPayload<E>> BlockProposalContents<E, Paylo
 
 // This just groups together a bunch of parameters that commonly
 // get passed around together in calls to get_payload.
-#[derive(Clone, Copy)]
+#[derive(Clone, Copy, Debug)]
 pub struct PayloadParameters<'a> {
     pub parent_hash: ExecutionBlockHash,
     pub parent_gas_limit: u64,
@@ -1822,6 +1830,7 @@ impl<E: EthSpec> ExecutionLayer<E> {
                 ForkName::Capella => ExecutionPayloadCapella::default().into(),
                 ForkName::Deneb => ExecutionPayloadDeneb::default().into(),
                 ForkName::Electra => ExecutionPayloadElectra::default().into(),
+                ForkName::Fulu => ExecutionPayloadFulu::default().into(),
                 ForkName::Base | ForkName::Altair => {
                     return Err(Error::InvalidForkForPayload);
                 }
@@ -2109,7 +2118,7 @@ fn verify_builder_bid<E: EthSpec>(
             payload: header.timestamp(),
             expected: payload_attributes.timestamp(),
         }))
-    } else if block_number.map_or(false, |n| n != header.block_number()) {
+    } else if block_number.is_some_and(|n| n != header.block_number()) {
         Err(Box::new(InvalidBuilderPayload::BlockNumber {
             payload: header.block_number(),
             expected: block_number,
diff --git a/beacon_node/execution_layer/src/payload_status.rs b/beacon_node/execution_layer/src/payload_status.rs
index 5405fd7009..cf0be8ed0d 100644
--- a/beacon_node/execution_layer/src/payload_status.rs
+++ b/beacon_node/execution_layer/src/payload_status.rs
@@ -41,7 +41,7 @@ pub fn process_payload_status(
             PayloadStatusV1Status::Valid => {
                 if response
                     .latest_valid_hash
-                    .map_or(false, |h| h == head_block_hash)
+                    .is_some_and(|h| h == head_block_hash)
                 {
                     // The response is only valid if `latest_valid_hash` is not `null` and
                     // equal to the provided `block_hash`.
diff --git a/beacon_node/execution_layer/src/test_utils/execution_block_generator.rs b/beacon_node/execution_layer/src/test_utils/execution_block_generator.rs
index 4fab7150ce..9fa375b375 100644
--- a/beacon_node/execution_layer/src/test_utils/execution_block_generator.rs
+++ b/beacon_node/execution_layer/src/test_utils/execution_block_generator.rs
@@ -19,7 +19,7 @@ use tree_hash::TreeHash;
 use tree_hash_derive::TreeHash;
 use types::{
     Blob, ChainSpec, EthSpec, ExecutionBlockHash, ExecutionPayload, ExecutionPayloadBellatrix,
-    ExecutionPayloadCapella, ExecutionPayloadDeneb, ExecutionPayloadElectra,
+    ExecutionPayloadCapella, ExecutionPayloadDeneb, ExecutionPayloadElectra, ExecutionPayloadFulu,
     ExecutionPayloadHeader, FixedBytesExtended, ForkName, Hash256, Transaction, Transactions,
     Uint256,
 };
@@ -147,12 +147,14 @@ pub struct ExecutionBlockGenerator<E: EthSpec> {
     pub shanghai_time: Option<u64>, // capella
     pub cancun_time: Option<u64>,   // deneb
     pub prague_time: Option<u64>,   // electra
+    pub osaka_time: Option<u64>,    // fulu
     /*
      * deneb stuff
      */
     pub blobs_bundles: HashMap<PayloadId, BlobsBundle<E>>,
     pub kzg: Option<Arc<Kzg>>,
     rng: Arc<Mutex<StdRng>>,
+    spec: Arc<ChainSpec>,
 }
 
 fn make_rng() -> Arc<Mutex<StdRng>> {
@@ -162,6 +164,7 @@ fn make_rng() -> Arc<Mutex<StdRng>> {
 }
 
 impl<E: EthSpec> ExecutionBlockGenerator<E> {
+    #[allow(clippy::too_many_arguments)]
     pub fn new(
         terminal_total_difficulty: Uint256,
         terminal_block_number: u64,
@@ -169,6 +172,8 @@ impl<E: EthSpec> ExecutionBlockGenerator<E> {
         shanghai_time: Option<u64>,
         cancun_time: Option<u64>,
         prague_time: Option<u64>,
+        osaka_time: Option<u64>,
+        spec: Arc<ChainSpec>,
         kzg: Option<Arc<Kzg>>,
     ) -> Self {
         let mut gen = Self {
@@ -185,9 +190,11 @@ impl<E: EthSpec> ExecutionBlockGenerator<E> {
             shanghai_time,
             cancun_time,
             prague_time,
+            osaka_time,
             blobs_bundles: <_>::default(),
             kzg,
             rng: make_rng(),
+            spec,
         };
 
         gen.insert_pow_block(0).unwrap();
@@ -233,13 +240,16 @@ impl<E: EthSpec> ExecutionBlockGenerator<E> {
     }
 
     pub fn get_fork_at_timestamp(&self, timestamp: u64) -> ForkName {
-        match self.prague_time {
-            Some(fork_time) if timestamp >= fork_time => ForkName::Electra,
-            _ => match self.cancun_time {
-                Some(fork_time) if timestamp >= fork_time => ForkName::Deneb,
-                _ => match self.shanghai_time {
-                    Some(fork_time) if timestamp >= fork_time => ForkName::Capella,
-                    _ => ForkName::Bellatrix,
+        match self.osaka_time {
+            Some(fork_time) if timestamp >= fork_time => ForkName::Fulu,
+            _ => match self.prague_time {
+                Some(fork_time) if timestamp >= fork_time => ForkName::Electra,
+                _ => match self.cancun_time {
+                    Some(fork_time) if timestamp >= fork_time => ForkName::Deneb,
+                    _ => match self.shanghai_time {
+                        Some(fork_time) if timestamp >= fork_time => ForkName::Capella,
+                        _ => ForkName::Bellatrix,
+                    },
                 },
             },
         }
@@ -664,6 +674,25 @@ impl<E: EthSpec> ExecutionBlockGenerator<E> {
                     blob_gas_used: 0,
                     excess_blob_gas: 0,
                 }),
+                ForkName::Fulu => ExecutionPayload::Fulu(ExecutionPayloadFulu {
+                    parent_hash: head_block_hash,
+                    fee_recipient: pa.suggested_fee_recipient,
+                    receipts_root: Hash256::repeat_byte(42),
+                    state_root: Hash256::repeat_byte(43),
+                    logs_bloom: vec![0; 256].into(),
+                    prev_randao: pa.prev_randao,
+                    block_number: parent.block_number() + 1,
+                    gas_limit: DEFAULT_GAS_LIMIT,
+                    gas_used: GAS_USED,
+                    timestamp: pa.timestamp,
+                    extra_data: "block gen was here".as_bytes().to_vec().into(),
+                    base_fee_per_gas: Uint256::from(1u64),
+                    block_hash: ExecutionBlockHash::zero(),
+                    transactions: vec![].into(),
+                    withdrawals: pa.withdrawals.clone().into(),
+                    blob_gas_used: 0,
+                    excess_blob_gas: 0,
+                }),
                 _ => unreachable!(),
             },
         };
@@ -671,7 +700,11 @@ impl<E: EthSpec> ExecutionBlockGenerator<E> {
         if execution_payload.fork_name().deneb_enabled() {
             // get random number between 0 and Max Blobs
             let mut rng = self.rng.lock();
-            let num_blobs = rng.gen::<usize>() % (E::max_blobs_per_block() + 1);
+            let max_blobs = self
+                .spec
+                .max_blobs_per_block_by_fork(execution_payload.fork_name())
+                as usize;
+            let num_blobs = rng.gen::<usize>() % (max_blobs + 1);
             let (bundle, transactions) = generate_blobs(num_blobs)?;
             for tx in Vec::from(transactions) {
                 execution_payload
@@ -811,6 +844,12 @@ pub fn generate_genesis_header<E: EthSpec>(
             *header.transactions_root_mut() = empty_transactions_root;
             Some(header)
         }
+        ForkName::Fulu => {
+            let mut header = ExecutionPayloadHeader::Fulu(<_>::default());
+            *header.block_hash_mut() = genesis_block_hash.unwrap_or_default();
+            *header.transactions_root_mut() = empty_transactions_root;
+            Some(header)
+        }
     }
 }
 
@@ -874,6 +913,7 @@ mod test {
         const TERMINAL_DIFFICULTY: u64 = 10;
         const TERMINAL_BLOCK: u64 = 10;
         const DIFFICULTY_INCREMENT: u64 = 1;
+        let spec = Arc::new(MainnetEthSpec::default_spec());
 
         let mut generator: ExecutionBlockGenerator<MainnetEthSpec> = ExecutionBlockGenerator::new(
             Uint256::from(TERMINAL_DIFFICULTY),
@@ -883,6 +923,8 @@ mod test {
             None,
             None,
             None,
+            spec,
+            None,
         );
 
         for i in 0..=TERMINAL_BLOCK {
diff --git a/beacon_node/execution_layer/src/test_utils/handle_rpc.rs b/beacon_node/execution_layer/src/test_utils/handle_rpc.rs
index 9365024ffb..d727d2c159 100644
--- a/beacon_node/execution_layer/src/test_utils/handle_rpc.rs
+++ b/beacon_node/execution_layer/src/test_utils/handle_rpc.rs
@@ -99,7 +99,8 @@ pub async fn handle_rpc<E: EthSpec>(
         ENGINE_NEW_PAYLOAD_V1
         | ENGINE_NEW_PAYLOAD_V2
         | ENGINE_NEW_PAYLOAD_V3
-        | ENGINE_NEW_PAYLOAD_V4 => {
+        | ENGINE_NEW_PAYLOAD_V4
+        | ENGINE_NEW_PAYLOAD_V5 => {
             let request = match method {
                 ENGINE_NEW_PAYLOAD_V1 => JsonExecutionPayload::V1(
                     get_param::<JsonExecutionPayloadV1<E>>(params, 0)
@@ -121,6 +122,9 @@ pub async fn handle_rpc<E: EthSpec>(
                 ENGINE_NEW_PAYLOAD_V4 => get_param::<JsonExecutionPayloadV4<E>>(params, 0)
                     .map(|jep| JsonExecutionPayload::V4(jep))
                     .map_err(|s| (s, BAD_PARAMS_ERROR_CODE))?,
+                ENGINE_NEW_PAYLOAD_V5 => get_param::<JsonExecutionPayloadV5<E>>(params, 0)
+                    .map(|jep| JsonExecutionPayload::V5(jep))
+                    .map_err(|s| (s, BAD_PARAMS_ERROR_CODE))?,
                 _ => unreachable!(),
             };
 
@@ -222,6 +226,56 @@ pub async fn handle_rpc<E: EthSpec>(
                         ));
                     }
                 }
+                ForkName::Fulu => {
+                    if method == ENGINE_NEW_PAYLOAD_V1
+                        || method == ENGINE_NEW_PAYLOAD_V2
+                        || method == ENGINE_NEW_PAYLOAD_V3
+                    // TODO(fulu): Uncomment this once v5 method is ready for Fulu
+                    // || method == ENGINE_NEW_PAYLOAD_V4
+                    {
+                        return Err((
+                            format!("{} called after Fulu fork!", method),
+                            GENERIC_ERROR_CODE,
+                        ));
+                    }
+                    if matches!(request, JsonExecutionPayload::V1(_)) {
+                        return Err((
+                            format!(
+                                "{} called with `ExecutionPayloadV1` after Fulu fork!",
+                                method
+                            ),
+                            GENERIC_ERROR_CODE,
+                        ));
+                    }
+                    if matches!(request, JsonExecutionPayload::V2(_)) {
+                        return Err((
+                            format!(
+                                "{} called with `ExecutionPayloadV2` after Fulu fork!",
+                                method
+                            ),
+                            GENERIC_ERROR_CODE,
+                        ));
+                    }
+                    if matches!(request, JsonExecutionPayload::V3(_)) {
+                        return Err((
+                            format!(
+                                "{} called with `ExecutionPayloadV3` after Fulu fork!",
+                                method
+                            ),
+                            GENERIC_ERROR_CODE,
+                        ));
+                    }
+                    // TODO(fulu): remove once we switch to v5
+                    // if matches!(request, JsonExecutionPayload::V4(_)) {
+                    //     return Err((
+                    //         format!(
+                    //             "{} called with `ExecutionPayloadV4` after Fulu fork!",
+                    //             method
+                    //         ),
+                    //         GENERIC_ERROR_CODE,
+                    //     ));
+                    // }
+                }
                 _ => unreachable!(),
             };
 
@@ -260,7 +314,8 @@ pub async fn handle_rpc<E: EthSpec>(
         ENGINE_GET_PAYLOAD_V1
         | ENGINE_GET_PAYLOAD_V2
         | ENGINE_GET_PAYLOAD_V3
-        | ENGINE_GET_PAYLOAD_V4 => {
+        | ENGINE_GET_PAYLOAD_V4
+        | ENGINE_GET_PAYLOAD_V5 => {
             let request: JsonPayloadIdRequest =
                 get_param(params, 0).map_err(|s| (s, BAD_PARAMS_ERROR_CODE))?;
             let id = request.into();
@@ -320,6 +375,24 @@ pub async fn handle_rpc<E: EthSpec>(
                 ));
             }
 
+            // validate method called correctly according to fulu fork time
+            if ctx
+                .execution_block_generator
+                .read()
+                .get_fork_at_timestamp(response.timestamp())
+                == ForkName::Fulu
+                && (method == ENGINE_GET_PAYLOAD_V1
+                    || method == ENGINE_GET_PAYLOAD_V2
+                    || method == ENGINE_GET_PAYLOAD_V3)
+            // TODO(fulu): Uncomment this once v5 method is ready for Fulu
+            // || method == ENGINE_GET_PAYLOAD_V4)
+            {
+                return Err((
+                    format!("{} called after Fulu fork!", method),
+                    FORK_REQUEST_MISMATCH_ERROR_CODE,
+                ));
+            }
+
             match method {
                 ENGINE_GET_PAYLOAD_V1 => {
                     Ok(serde_json::to_value(JsonExecutionPayload::from(response)).unwrap())
@@ -378,6 +451,40 @@ pub async fn handle_rpc<E: EthSpec>(
                         })
                         .unwrap()
                     }
+                    // TODO(fulu): remove this once we switch to v5 method
+                    JsonExecutionPayload::V5(execution_payload) => {
+                        serde_json::to_value(JsonGetPayloadResponseV5 {
+                            execution_payload,
+                            block_value: Uint256::from(DEFAULT_MOCK_EL_PAYLOAD_VALUE_WEI),
+                            blobs_bundle: maybe_blobs
+                                .ok_or((
+                                    "No blobs returned despite V5 Payload".to_string(),
+                                    GENERIC_ERROR_CODE,
+                                ))?
+                                .into(),
+                            should_override_builder: false,
+                            execution_requests: Default::default(),
+                        })
+                        .unwrap()
+                    }
+                    _ => unreachable!(),
+                }),
+                ENGINE_GET_PAYLOAD_V5 => Ok(match JsonExecutionPayload::from(response) {
+                    JsonExecutionPayload::V5(execution_payload) => {
+                        serde_json::to_value(JsonGetPayloadResponseV5 {
+                            execution_payload,
+                            block_value: Uint256::from(DEFAULT_MOCK_EL_PAYLOAD_VALUE_WEI),
+                            blobs_bundle: maybe_blobs
+                                .ok_or((
+                                    "No blobs returned despite V5 Payload".to_string(),
+                                    GENERIC_ERROR_CODE,
+                                ))?
+                                .into(),
+                            should_override_builder: false,
+                            execution_requests: Default::default(),
+                        })
+                        .unwrap()
+                    }
                     _ => unreachable!(),
                 }),
                 _ => unreachable!(),
@@ -411,7 +518,10 @@ pub async fn handle_rpc<E: EthSpec>(
                                             .map(|opt| opt.map(JsonPayloadAttributes::V1))
                                             .transpose()
                                     }
-                                    ForkName::Capella | ForkName::Deneb | ForkName::Electra => {
+                                    ForkName::Capella
+                                    | ForkName::Deneb
+                                    | ForkName::Electra
+                                    | ForkName::Fulu => {
                                         get_param::<Option<JsonPayloadAttributesV2>>(params, 1)
                                             .map(|opt| opt.map(JsonPayloadAttributes::V2))
                                             .transpose()
@@ -475,7 +585,7 @@ pub async fn handle_rpc<E: EthSpec>(
                             ));
                         }
                     }
-                    ForkName::Deneb | ForkName::Electra => {
+                    ForkName::Deneb | ForkName::Electra | ForkName::Fulu => {
                         if method == ENGINE_FORKCHOICE_UPDATED_V1 {
                             return Err((
                                 format!("{} called after Deneb fork!", method),
diff --git a/beacon_node/execution_layer/src/test_utils/mock_builder.rs b/beacon_node/execution_layer/src/test_utils/mock_builder.rs
index 879b54eb07..3540909fe4 100644
--- a/beacon_node/execution_layer/src/test_utils/mock_builder.rs
+++ b/beacon_node/execution_layer/src/test_utils/mock_builder.rs
@@ -1,10 +1,15 @@
 use crate::test_utils::{DEFAULT_BUILDER_PAYLOAD_VALUE_WEI, DEFAULT_JWT_SECRET};
 use crate::{Config, ExecutionLayer, PayloadAttributes, PayloadParameters};
-use eth2::types::{BlobsBundle, BlockId, StateId, ValidatorId};
+use eth2::types::PublishBlockRequest;
+use eth2::types::{
+    BlobsBundle, BlockId, BroadcastValidation, EventKind, EventTopic, FullPayloadContents,
+    ProposerData, StateId, ValidatorId,
+};
 use eth2::{BeaconNodeHttpClient, Timeouts, CONSENSUS_VERSION_HEADER};
 use fork_choice::ForkchoiceUpdateParameters;
 use parking_lot::RwLock;
 use sensitive_url::SensitiveUrl;
+use slog::{debug, error, info, warn, Logger};
 use std::collections::HashMap;
 use std::fmt::Debug;
 use std::future::Future;
@@ -13,20 +18,26 @@ use std::sync::Arc;
 use std::time::Duration;
 use task_executor::TaskExecutor;
 use tempfile::NamedTempFile;
+use tokio_stream::StreamExt;
 use tree_hash::TreeHash;
 use types::builder_bid::{
     BuilderBid, BuilderBidBellatrix, BuilderBidCapella, BuilderBidDeneb, BuilderBidElectra,
-    SignedBuilderBid,
+    BuilderBidFulu, SignedBuilderBid,
 };
 use types::{
-    Address, BeaconState, ChainSpec, EthSpec, ExecPayload, ExecutionPayload,
-    ExecutionPayloadHeaderRefMut, ExecutionRequests, FixedBytesExtended, ForkName,
-    ForkVersionedResponse, Hash256, PublicKeyBytes, Signature, SignedBlindedBeaconBlock,
-    SignedRoot, SignedValidatorRegistrationData, Slot, Uint256,
+    Address, BeaconState, ChainSpec, Epoch, EthSpec, ExecPayload, ExecutionPayload,
+    ExecutionPayloadHeaderRefMut, ExecutionRequests, ForkName, ForkVersionedResponse, Hash256,
+    PublicKeyBytes, Signature, SignedBlindedBeaconBlock, SignedRoot,
+    SignedValidatorRegistrationData, Slot, Uint256,
 };
 use types::{ExecutionBlockHash, SecretKey};
 use warp::{Filter, Rejection};
 
+pub const DEFAULT_FEE_RECIPIENT: Address = Address::repeat_byte(42);
+pub const DEFAULT_GAS_LIMIT: u64 = 30_000_000;
+pub const DEFAULT_BUILDER_PRIVATE_KEY: &str =
+    "607a11b45a7219cc61a3d9c5fd08c7eebd602a6a19a977f8d3771d5711a550f2";
+
 #[derive(Clone)]
 pub enum Operation {
     FeeRecipient(Address),
@@ -95,6 +106,9 @@ impl<E: EthSpec> BidStuff<E> for BuilderBid<E> {
             ExecutionPayloadHeaderRefMut::Electra(header) => {
                 header.fee_recipient = fee_recipient;
             }
+            ExecutionPayloadHeaderRefMut::Fulu(header) => {
+                header.fee_recipient = fee_recipient;
+            }
         }
     }
 
@@ -112,6 +126,9 @@ impl<E: EthSpec> BidStuff<E> for BuilderBid<E> {
             ExecutionPayloadHeaderRefMut::Electra(header) => {
                 header.gas_limit = gas_limit;
             }
+            ExecutionPayloadHeaderRefMut::Fulu(header) => {
+                header.gas_limit = gas_limit;
+            }
         }
     }
 
@@ -133,6 +150,9 @@ impl<E: EthSpec> BidStuff<E> for BuilderBid<E> {
             ExecutionPayloadHeaderRefMut::Electra(header) => {
                 header.parent_hash = ExecutionBlockHash::from_root(parent_hash);
             }
+            ExecutionPayloadHeaderRefMut::Fulu(header) => {
+                header.parent_hash = ExecutionBlockHash::from_root(parent_hash);
+            }
         }
     }
 
@@ -150,6 +170,9 @@ impl<E: EthSpec> BidStuff<E> for BuilderBid<E> {
             ExecutionPayloadHeaderRefMut::Electra(header) => {
                 header.prev_randao = prev_randao;
             }
+            ExecutionPayloadHeaderRefMut::Fulu(header) => {
+                header.prev_randao = prev_randao;
+            }
         }
     }
 
@@ -167,6 +190,9 @@ impl<E: EthSpec> BidStuff<E> for BuilderBid<E> {
             ExecutionPayloadHeaderRefMut::Electra(header) => {
                 header.block_number = block_number;
             }
+            ExecutionPayloadHeaderRefMut::Fulu(header) => {
+                header.block_number = block_number;
+            }
         }
     }
 
@@ -184,6 +210,9 @@ impl<E: EthSpec> BidStuff<E> for BuilderBid<E> {
             ExecutionPayloadHeaderRefMut::Electra(header) => {
                 header.timestamp = timestamp;
             }
+            ExecutionPayloadHeaderRefMut::Fulu(header) => {
+                header.timestamp = timestamp;
+            }
         }
     }
 
@@ -201,6 +230,9 @@ impl<E: EthSpec> BidStuff<E> for BuilderBid<E> {
             ExecutionPayloadHeaderRefMut::Electra(header) => {
                 header.withdrawals_root = withdrawals_root;
             }
+            ExecutionPayloadHeaderRefMut::Fulu(header) => {
+                header.withdrawals_root = withdrawals_root;
+            }
         }
     }
 
@@ -230,10 +262,25 @@ impl<E: EthSpec> BidStuff<E> for BuilderBid<E> {
                 header.extra_data = extra_data;
                 header.block_hash = ExecutionBlockHash::from_root(header.tree_hash_root());
             }
+            ExecutionPayloadHeaderRefMut::Fulu(header) => {
+                header.extra_data = extra_data;
+                header.block_hash = ExecutionBlockHash::from_root(header.tree_hash_root());
+            }
         }
     }
 }
 
+// Non referenced version of `PayloadParameters`
+#[derive(Clone)]
+pub struct PayloadParametersCloned {
+    pub parent_hash: ExecutionBlockHash,
+    pub parent_gas_limit: u64,
+    pub proposer_gas_limit: Option<u64>,
+    pub payload_attributes: PayloadAttributes,
+    pub forkchoice_update_params: ForkchoiceUpdateParameters,
+    pub current_fork: ForkName,
+}
+
 #[derive(Clone)]
 pub struct MockBuilder<E: EthSpec> {
     el: ExecutionLayer<E>,
@@ -243,6 +290,20 @@ pub struct MockBuilder<E: EthSpec> {
     builder_sk: SecretKey,
     operations: Arc<RwLock<Vec<Operation>>>,
     invalidate_signatures: Arc<RwLock<bool>>,
+    genesis_time: Option<u64>,
+    /// Only returns bids for registered validators if set to true. `true` by default.
+    validate_pubkey: bool,
+    /// Do not apply any operations if set to `false`.
+    /// Applying operations might modify the cached header in the execution layer.
+    /// Use this if you want get_header to return a valid bid that can be eventually submitted as
+    /// a valid block.
+    apply_operations: bool,
+    payload_id_cache: Arc<RwLock<HashMap<ExecutionBlockHash, PayloadParametersCloned>>>,
+    /// If set to `true`, sets the bid returned by `get_header` to Uint256::MAX
+    max_bid: bool,
+    /// A cache that stores the proposers index for a given epoch
+    proposers_cache: Arc<RwLock<HashMap<Epoch, Vec<ProposerData>>>>,
+    log: Logger,
 }
 
 impl<E: EthSpec> MockBuilder<E> {
@@ -270,7 +331,12 @@ impl<E: EthSpec> MockBuilder<E> {
         let builder = MockBuilder::new(
             el,
             BeaconNodeHttpClient::new(beacon_url, Timeouts::set_all(Duration::from_secs(1))),
+            true,
+            true,
+            false,
             spec,
+            None,
+            executor.log().clone(),
         );
         let host: Ipv4Addr = Ipv4Addr::LOCALHOST;
         let port = 0;
@@ -278,21 +344,47 @@ impl<E: EthSpec> MockBuilder<E> {
         (builder, server)
     }
 
+    #[allow(clippy::too_many_arguments)]
     pub fn new(
         el: ExecutionLayer<E>,
         beacon_client: BeaconNodeHttpClient,
+        validate_pubkey: bool,
+        apply_operations: bool,
+        max_bid: bool,
         spec: Arc<ChainSpec>,
+        sk: Option<&[u8]>,
+        log: Logger,
     ) -> Self {
-        let sk = SecretKey::random();
+        let builder_sk = if let Some(sk_bytes) = sk {
+            match SecretKey::deserialize(sk_bytes) {
+                Ok(sk) => sk,
+                Err(_) => {
+                    error!(
+                        log,
+                        "Invalid sk_bytes provided, generating random secret key"
+                    );
+                    SecretKey::random()
+                }
+            }
+        } else {
+            SecretKey::deserialize(&hex::decode(DEFAULT_BUILDER_PRIVATE_KEY).unwrap()).unwrap()
+        };
         Self {
             el,
             beacon_client,
             // Should keep spec and context consistent somehow
             spec,
             val_registration_cache: Arc::new(RwLock::new(HashMap::new())),
-            builder_sk: sk,
+            builder_sk,
+            validate_pubkey,
             operations: Arc::new(RwLock::new(vec![])),
             invalidate_signatures: Arc::new(RwLock::new(false)),
+            payload_id_cache: Arc::new(RwLock::new(HashMap::new())),
+            proposers_cache: Arc::new(RwLock::new(HashMap::new())),
+            apply_operations,
+            max_bid,
+            genesis_time: None,
+            log,
         }
     }
 
@@ -317,8 +409,523 @@ impl<E: EthSpec> MockBuilder<E> {
         }
         bid.stamp_payload();
     }
+
+    /// Return the public key of the builder
+    pub fn public_key(&self) -> PublicKeyBytes {
+        self.builder_sk.public_key().compress()
+    }
+
+    pub async fn register_validators(
+        &self,
+        registrations: Vec<SignedValidatorRegistrationData>,
+    ) -> Result<(), String> {
+        info!(
+            self.log,
+            "Registering validators";
+            "count" => registrations.len(),
+        );
+        for registration in registrations {
+            if !registration.verify_signature(&self.spec) {
+                error!(
+                    self.log,
+                    "Failed to register validator";
+                    "error" => "invalid signature",
+                    "validator" => %registration.message.pubkey
+                );
+                return Err("invalid signature".to_string());
+            }
+            self.val_registration_cache
+                .write()
+                .insert(registration.message.pubkey, registration);
+        }
+        Ok(())
+    }
+
+    pub async fn submit_blinded_block(
+        &self,
+        block: SignedBlindedBeaconBlock<E>,
+    ) -> Result<FullPayloadContents<E>, String> {
+        let root = match &block {
+            SignedBlindedBeaconBlock::Base(_) | types::SignedBeaconBlock::Altair(_) => {
+                return Err("invalid fork".to_string());
+            }
+            SignedBlindedBeaconBlock::Bellatrix(block) => {
+                block.message.body.execution_payload.tree_hash_root()
+            }
+            SignedBlindedBeaconBlock::Capella(block) => {
+                block.message.body.execution_payload.tree_hash_root()
+            }
+            SignedBlindedBeaconBlock::Deneb(block) => {
+                block.message.body.execution_payload.tree_hash_root()
+            }
+            SignedBlindedBeaconBlock::Electra(block) => {
+                block.message.body.execution_payload.tree_hash_root()
+            }
+            SignedBlindedBeaconBlock::Fulu(block) => {
+                block.message.body.execution_payload.tree_hash_root()
+            }
+        };
+        info!(
+            self.log,
+            "Submitting blinded beacon block to builder";
+            "block_hash" => %root
+        );
+        let payload = self
+            .el
+            .get_payload_by_root(&root)
+            .ok_or_else(|| "missing payload for tx root".to_string())?;
+
+        let (payload, blobs) = payload.deconstruct();
+        let full_block = block
+            .try_into_full_block(Some(payload.clone()))
+            .ok_or("Internal error, just provided a payload")?;
+        debug!(
+            self.log,
+            "Got full payload, sending to local beacon node for propagation";
+            "txs_count" => payload.transactions().len(),
+            "blob_count" => blobs.as_ref().map(|b| b.commitments.len())
+        );
+        let publish_block_request = PublishBlockRequest::new(
+            Arc::new(full_block),
+            blobs.clone().map(|b| (b.proofs, b.blobs)),
+        );
+        self.beacon_client
+            .post_beacon_blocks_v2(&publish_block_request, Some(BroadcastValidation::Gossip))
+            .await
+            .map_err(|e| format!("Failed to post blinded block {:?}", e))?;
+        Ok(FullPayloadContents::new(payload, blobs))
+    }
+
+    pub async fn get_header(
+        &self,
+        slot: Slot,
+        parent_hash: ExecutionBlockHash,
+        pubkey: PublicKeyBytes,
+    ) -> Result<SignedBuilderBid<E>, String> {
+        info!(self.log, "In get_header");
+        // Check if the pubkey has registered with the builder if required
+        if self.validate_pubkey && !self.val_registration_cache.read().contains_key(&pubkey) {
+            return Err("validator not registered with builder".to_string());
+        }
+        let payload_parameters = {
+            let mut guard = self.payload_id_cache.write();
+            guard.remove(&parent_hash)
+        };
+
+        let payload_parameters = match payload_parameters {
+            Some(params) => params,
+            None => {
+                warn!(
+                    self.log,
+                    "Payload params not cached for parent_hash {}", parent_hash
+                );
+                self.get_payload_params(slot, None, pubkey, None).await?
+            }
+        };
+
+        info!(self.log, "Got payload params");
+
+        let fork = self.fork_name_at_slot(slot);
+        let payload_response_type = self
+            .el
+            .get_full_payload_caching(PayloadParameters {
+                parent_hash: payload_parameters.parent_hash,
+                parent_gas_limit: payload_parameters.parent_gas_limit,
+                proposer_gas_limit: payload_parameters.proposer_gas_limit,
+                payload_attributes: &payload_parameters.payload_attributes,
+                forkchoice_update_params: &payload_parameters.forkchoice_update_params,
+                current_fork: payload_parameters.current_fork,
+            })
+            .await
+            .map_err(|e| format!("couldn't get payload {:?}", e))?;
+
+        info!(self.log, "Got payload message, fork {}", fork);
+
+        let mut message = match payload_response_type {
+            crate::GetPayloadResponseType::Full(payload_response) => {
+                #[allow(clippy::type_complexity)]
+                let (payload, value, maybe_blobs_bundle, maybe_requests): (
+                    ExecutionPayload<E>,
+                    Uint256,
+                    Option<BlobsBundle<E>>,
+                    Option<ExecutionRequests<E>>,
+                ) = payload_response.into();
+
+                match fork {
+                    ForkName::Fulu => BuilderBid::Fulu(BuilderBidFulu {
+                        header: payload
+                            .as_fulu()
+                            .map_err(|_| "incorrect payload variant".to_string())?
+                            .into(),
+                        blob_kzg_commitments: maybe_blobs_bundle
+                            .map(|b| b.commitments)
+                            .unwrap_or_default(),
+                        value: self.get_bid_value(value),
+                        pubkey: self.builder_sk.public_key().compress(),
+                        execution_requests: maybe_requests.unwrap_or_default(),
+                    }),
+                    ForkName::Electra => BuilderBid::Electra(BuilderBidElectra {
+                        header: payload
+                            .as_electra()
+                            .map_err(|_| "incorrect payload variant".to_string())?
+                            .into(),
+                        blob_kzg_commitments: maybe_blobs_bundle
+                            .map(|b| b.commitments)
+                            .unwrap_or_default(),
+                        value: self.get_bid_value(value),
+                        pubkey: self.builder_sk.public_key().compress(),
+                        execution_requests: maybe_requests.unwrap_or_default(),
+                    }),
+                    ForkName::Deneb => BuilderBid::Deneb(BuilderBidDeneb {
+                        header: payload
+                            .as_deneb()
+                            .map_err(|_| "incorrect payload variant".to_string())?
+                            .into(),
+                        blob_kzg_commitments: maybe_blobs_bundle
+                            .map(|b| b.commitments)
+                            .unwrap_or_default(),
+                        value: self.get_bid_value(value),
+                        pubkey: self.builder_sk.public_key().compress(),
+                    }),
+                    ForkName::Capella => BuilderBid::Capella(BuilderBidCapella {
+                        header: payload
+                            .as_capella()
+                            .map_err(|_| "incorrect payload variant".to_string())?
+                            .into(),
+                        value: self.get_bid_value(value),
+                        pubkey: self.builder_sk.public_key().compress(),
+                    }),
+                    ForkName::Bellatrix => BuilderBid::Bellatrix(BuilderBidBellatrix {
+                        header: payload
+                            .as_bellatrix()
+                            .map_err(|_| "incorrect payload variant".to_string())?
+                            .into(),
+                        value: self.get_bid_value(value),
+                        pubkey: self.builder_sk.public_key().compress(),
+                    }),
+                    ForkName::Base | ForkName::Altair => return Err("invalid fork".to_string()),
+                }
+            }
+            _ => panic!("just requested full payload, cannot get blinded"),
+        };
+
+        if self.apply_operations {
+            info!(self.log, "Applying operations");
+            self.apply_operations(&mut message);
+        }
+        info!(self.log, "Signing builder message");
+
+        let mut signature = message.sign_builder_message(&self.builder_sk, &self.spec);
+
+        if *self.invalidate_signatures.read() {
+            signature = Signature::empty();
+        };
+        let signed_bid = SignedBuilderBid { message, signature };
+        info!(self.log, "Builder bid {:?}", &signed_bid.message.value());
+        Ok(signed_bid)
+    }
+
+    fn fork_name_at_slot(&self, slot: Slot) -> ForkName {
+        self.spec.fork_name_at_slot::<E>(slot)
+    }
+
+    fn get_bid_value(&self, value: Uint256) -> Uint256 {
+        if self.max_bid {
+            Uint256::MAX
+        } else if !self.apply_operations {
+            value
+        } else {
+            Uint256::from(DEFAULT_BUILDER_PAYLOAD_VALUE_WEI)
+        }
+    }
+
+    /// Prepare the execution layer for payload creation every slot for the correct
+    /// proposer index
+    pub async fn prepare_execution_layer(&self) -> Result<(), String> {
+        info!(
+            self.log,
+            "Starting a task to prepare the execution layer";
+        );
+        let mut head_event_stream = self
+            .beacon_client
+            .get_events::<E>(&[EventTopic::Head])
+            .await
+            .map_err(|e| format!("Failed to get head event {:?}", e))?;
+
+        while let Some(Ok(event)) = head_event_stream.next().await {
+            match event {
+                EventKind::Head(head) => {
+                    debug!(
+                        self.log,
+                        "Got a new head event";
+                        "block_hash" => %head.block
+                    );
+                    let next_slot = head.slot + 1;
+                    // Find the next proposer index from the cached data or through a beacon api call
+                    let epoch = next_slot.epoch(E::slots_per_epoch());
+                    let position_in_slot = next_slot.as_u64() % E::slots_per_epoch();
+                    let proposer_data = {
+                        let proposers_opt = {
+                            let proposers_cache = self.proposers_cache.read();
+                            proposers_cache.get(&epoch).cloned()
+                        };
+                        match proposers_opt {
+                            Some(proposers) => proposers
+                                .get(position_in_slot as usize)
+                                .expect("position in slot is max epoch size")
+                                .clone(),
+                            None => {
+                                // make a call to the beacon api and populate the cache
+                                let duties: Vec<_> = self
+                                    .beacon_client
+                                    .get_validator_duties_proposer(epoch)
+                                    .await
+                                    .map_err(|e| {
+                                        format!(
+                                            "Failed to get proposer duties for epoch: {}, {:?}",
+                                            epoch, e
+                                        )
+                                    })?
+                                    .data;
+                                let proposer_data = duties
+                                    .get(position_in_slot as usize)
+                                    .expect("position in slot is max epoch size")
+                                    .clone();
+                                self.proposers_cache.write().insert(epoch, duties);
+                                proposer_data
+                            }
+                        }
+                    };
+                    self.prepare_execution_layer_internal(
+                        head.slot,
+                        head.block,
+                        proposer_data.validator_index,
+                        proposer_data.pubkey,
+                    )
+                    .await?;
+                }
+                e => {
+                    warn!(
+                        self.log,
+                        "Got an unexpected event";
+                        "event" => %e.topic_name()
+                    );
+                }
+            }
+        }
+        Ok(())
+    }
+
+    async fn prepare_execution_layer_internal(
+        &self,
+        current_slot: Slot,
+        head_block_root: Hash256,
+        validator_index: u64,
+        pubkey: PublicKeyBytes,
+    ) -> Result<(), String> {
+        let next_slot = current_slot + 1;
+        let payload_parameters = self
+            .get_payload_params(
+                next_slot,
+                Some(head_block_root),
+                pubkey,
+                Some(validator_index),
+            )
+            .await?;
+
+        self.payload_id_cache
+            .write()
+            .insert(payload_parameters.parent_hash, payload_parameters);
+        Ok(())
+    }
+
+    /// Get the `PayloadParameters` for requesting an ExecutionPayload for `slot`
+    /// for the given `validator_index` and `pubkey`.
+    async fn get_payload_params(
+        &self,
+        slot: Slot,
+        head_block_root: Option<Hash256>,
+        pubkey: PublicKeyBytes,
+        validator_index: Option<u64>,
+    ) -> Result<PayloadParametersCloned, String> {
+        let fork = self.fork_name_at_slot(slot);
+
+        let block_id = match head_block_root {
+            Some(block_root) => BlockId::Root(block_root),
+            None => BlockId::Head,
+        };
+        let head = self
+            .beacon_client
+            .get_beacon_blocks::<E>(block_id)
+            .await
+            .map_err(|_| "couldn't get head".to_string())?
+            .ok_or_else(|| "missing head block".to_string())?
+            .data;
+
+        let head_block_root = head_block_root.unwrap_or(head.canonical_root());
+
+        let head_execution_payload = head
+            .message()
+            .body()
+            .execution_payload()
+            .map_err(|_| "pre-merge block".to_string())?;
+        let head_execution_hash = head_execution_payload.block_hash();
+        let head_gas_limit = head_execution_payload.gas_limit();
+
+        let finalized_execution_hash = self
+            .beacon_client
+            .get_beacon_blocks::<E>(BlockId::Finalized)
+            .await
+            .map_err(|_| "couldn't get finalized block".to_string())?
+            .ok_or_else(|| "missing finalized block".to_string())?
+            .data
+            .message()
+            .body()
+            .execution_payload()
+            .map_err(|_| "pre-merge block".to_string())?
+            .block_hash();
+
+        let justified_execution_hash = self
+            .beacon_client
+            .get_beacon_blocks::<E>(BlockId::Justified)
+            .await
+            .map_err(|_| "couldn't get justified block".to_string())?
+            .ok_or_else(|| "missing justified block".to_string())?
+            .data
+            .message()
+            .body()
+            .execution_payload()
+            .map_err(|_| "pre-merge block".to_string())?
+            .block_hash();
+
+        let (fee_recipient, proposer_gas_limit) =
+            match self.val_registration_cache.read().get(&pubkey) {
+                Some(cached_data) => (
+                    cached_data.message.fee_recipient,
+                    cached_data.message.gas_limit,
+                ),
+                None => {
+                    warn!(
+                        self.log,
+                        "Validator not registered {}, using default fee recipient and gas limits",
+                        pubkey
+                    );
+                    (DEFAULT_FEE_RECIPIENT, DEFAULT_GAS_LIMIT)
+                }
+            };
+        let slots_since_genesis = slot.as_u64() - self.spec.genesis_slot.as_u64();
+
+        let genesis_time = if let Some(genesis_time) = self.genesis_time {
+            genesis_time
+        } else {
+            self.beacon_client
+                .get_beacon_genesis()
+                .await
+                .map_err(|_| "couldn't get beacon genesis".to_string())?
+                .data
+                .genesis_time
+        };
+        let timestamp = (slots_since_genesis * self.spec.seconds_per_slot) + genesis_time;
+
+        let head_state: BeaconState<E> = self
+            .beacon_client
+            .get_debug_beacon_states(StateId::Head)
+            .await
+            .map_err(|_| "couldn't get state".to_string())?
+            .ok_or_else(|| "missing state".to_string())?
+            .data;
+
+        let prev_randao = head_state
+            .get_randao_mix(head_state.current_epoch())
+            .map_err(|_| "couldn't get prev randao".to_string())?;
+
+        let expected_withdrawals = if fork.capella_enabled() {
+            Some(
+                self.beacon_client
+                    .get_expected_withdrawals(&StateId::Head)
+                    .await
+                    .map_err(|e| format!("Failed to get expected withdrawals: {:?}", e))?
+                    .data,
+            )
+        } else {
+            None
+        };
+
+        let payload_attributes = match fork {
+            // the withdrawals root is filled in by operations, but we supply the valid withdrawals
+            // first to avoid polluting the execution block generator with invalid payload attributes
+            // NOTE: this was part of an effort to add payload attribute uniqueness checks,
+            // which was abandoned because it broke too many tests in subtle ways.
+            ForkName::Bellatrix | ForkName::Capella => PayloadAttributes::new(
+                timestamp,
+                *prev_randao,
+                fee_recipient,
+                expected_withdrawals,
+                None,
+            ),
+            ForkName::Deneb | ForkName::Electra | ForkName::Fulu => PayloadAttributes::new(
+                timestamp,
+                *prev_randao,
+                fee_recipient,
+                expected_withdrawals,
+                Some(head_block_root),
+            ),
+            ForkName::Base | ForkName::Altair => {
+                return Err("invalid fork".to_string());
+            }
+        };
+
+        // Tells the execution layer that the `validator_index` is expected to propose
+        // a block on top of `head_block_root` for the given slot
+        let val_index = validator_index.unwrap_or(
+            self.beacon_client
+                .get_beacon_states_validator_id(StateId::Head, &ValidatorId::PublicKey(pubkey))
+                .await
+                .map_err(|_| "couldn't get validator".to_string())?
+                .ok_or_else(|| "missing validator".to_string())?
+                .data
+                .index,
+        );
+
+        self.el
+            .insert_proposer(slot, head_block_root, val_index, payload_attributes.clone())
+            .await;
+
+        let forkchoice_update_params = ForkchoiceUpdateParameters {
+            head_hash: Some(head_execution_hash),
+            finalized_hash: Some(finalized_execution_hash),
+            justified_hash: Some(justified_execution_hash),
+            head_root: head_block_root,
+        };
+
+        let _status = self
+            .el
+            .notify_forkchoice_updated(
+                head_execution_hash,
+                justified_execution_hash,
+                finalized_execution_hash,
+                slot - 1,
+                head_block_root,
+            )
+            .await
+            .map_err(|e| format!("fcu call failed : {:?}", e))?;
+
+        let payload_parameters = PayloadParametersCloned {
+            parent_hash: head_execution_hash,
+            parent_gas_limit: head_gas_limit,
+            proposer_gas_limit: Some(proposer_gas_limit),
+            payload_attributes,
+            forkchoice_update_params,
+            current_fork: fork,
+        };
+        Ok(payload_parameters)
+    }
 }
 
+/// Serve the builder api using warp. Uses the functions defined in `MockBuilder` to serve
+/// the requests.
+///
+/// We should eventually move this to axum when we move everything else.
 pub fn serve<E: EthSpec>(
     listen_addr: Ipv4Addr,
     listen_port: u16,
@@ -337,19 +944,16 @@ pub fn serve<E: EthSpec>(
         .and(warp::path::end())
         .and(ctx_filter.clone())
         .and_then(
-            |registrations: Vec<SignedValidatorRegistrationData>, builder: MockBuilder<E>| async move {
-                for registration in registrations {
-                    if !registration.verify_signature(&builder.spec) {
-                        return Err(reject("invalid signature"));
-                    }
-                    builder
-                        .val_registration_cache
-                        .write()
-                        .insert(registration.message.pubkey, registration);
-                }
-                Ok(warp::reply())
+            |registrations: Vec<SignedValidatorRegistrationData>,
+             builder: MockBuilder<E>| async move {
+                builder
+                    .register_validators(registrations)
+                    .await
+                    .map_err(|e| warp::reject::custom(Custom(e)))?;
+                Ok::<_, Rejection>(warp::reply())
             },
-        );
+        )
+        .boxed();
 
     let blinded_block =
         prefix
@@ -362,27 +966,10 @@ pub fn serve<E: EthSpec>(
                 |block: SignedBlindedBeaconBlock<E>,
                  fork_name: ForkName,
                  builder: MockBuilder<E>| async move {
-                    let root = match block {
-                        SignedBlindedBeaconBlock::Base(_) | types::SignedBeaconBlock::Altair(_) => {
-                            return Err(reject("invalid fork"));
-                        }
-                        SignedBlindedBeaconBlock::Bellatrix(block) => {
-                            block.message.body.execution_payload.tree_hash_root()
-                        }
-                        SignedBlindedBeaconBlock::Capella(block) => {
-                            block.message.body.execution_payload.tree_hash_root()
-                        }
-                        SignedBlindedBeaconBlock::Deneb(block) => {
-                            block.message.body.execution_payload.tree_hash_root()
-                        }
-                        SignedBlindedBeaconBlock::Electra(block) => {
-                            block.message.body.execution_payload.tree_hash_root()
-                        }
-                    };
                     let payload = builder
-                        .el
-                        .get_payload_by_root(&root)
-                        .ok_or_else(|| reject("missing payload for tx root"))?;
+                        .submit_blinded_block(block)
+                        .await
+                        .map_err(|e| warp::reject::custom(Custom(e)))?;
                     let resp: ForkVersionedResponse<_> = ForkVersionedResponse {
                         version: Some(fork_name),
                         metadata: Default::default(),
@@ -425,283 +1012,12 @@ pub fn serve<E: EthSpec>(
              parent_hash: ExecutionBlockHash,
              pubkey: PublicKeyBytes,
              builder: MockBuilder<E>| async move {
-                let fork = builder.spec.fork_name_at_slot::<E>(slot);
-                let signed_cached_data = builder
-                    .val_registration_cache
-                    .read()
-                    .get(&pubkey)
-                    .ok_or_else(|| reject("missing registration"))?
-                    .clone();
-                let cached_data = signed_cached_data.message;
-
-                let head = builder
-                    .beacon_client
-                    .get_beacon_blocks::<E>(BlockId::Head)
+                let fork_name = builder.fork_name_at_slot(slot);
+                let signed_bid = builder
+                    .get_header(slot, parent_hash, pubkey)
                     .await
-                    .map_err(|_| reject("couldn't get head"))?
-                    .ok_or_else(|| reject("missing head block"))?;
+                    .map_err(|e| warp::reject::custom(Custom(e)))?;
 
-                let block = head.data.message();
-                let head_block_root = block.tree_hash_root();
-                let head_execution_payload = block
-                    .body()
-                    .execution_payload()
-                    .map_err(|_| reject("pre-merge block"))?;
-                let head_execution_hash = head_execution_payload.block_hash();
-                let head_gas_limit = head_execution_payload.gas_limit();
-                if head_execution_hash != parent_hash {
-                    return Err(reject("head mismatch"));
-                }
-
-                let finalized_execution_hash = builder
-                    .beacon_client
-                    .get_beacon_blocks::<E>(BlockId::Finalized)
-                    .await
-                    .map_err(|_| reject("couldn't get finalized block"))?
-                    .ok_or_else(|| reject("missing finalized block"))?
-                    .data
-                    .message()
-                    .body()
-                    .execution_payload()
-                    .map_err(|_| reject("pre-merge block"))?
-                    .block_hash();
-
-                let justified_execution_hash = builder
-                    .beacon_client
-                    .get_beacon_blocks::<E>(BlockId::Justified)
-                    .await
-                    .map_err(|_| reject("couldn't get justified block"))?
-                    .ok_or_else(|| reject("missing justified block"))?
-                    .data
-                    .message()
-                    .body()
-                    .execution_payload()
-                    .map_err(|_| reject("pre-merge block"))?
-                    .block_hash();
-
-                let val_index = builder
-                    .beacon_client
-                    .get_beacon_states_validator_id(StateId::Head, &ValidatorId::PublicKey(pubkey))
-                    .await
-                    .map_err(|_| reject("couldn't get validator"))?
-                    .ok_or_else(|| reject("missing validator"))?
-                    .data
-                    .index;
-                let fee_recipient = cached_data.fee_recipient;
-                let slots_since_genesis = slot.as_u64() - builder.spec.genesis_slot.as_u64();
-
-                let genesis_data = builder
-                    .beacon_client
-                    .get_beacon_genesis()
-                    .await
-                    .map_err(|_| reject("couldn't get beacon genesis"))?
-                    .data;
-                let genesis_time = genesis_data.genesis_time;
-                let timestamp =
-                    (slots_since_genesis * builder.spec.seconds_per_slot) + genesis_time;
-
-                let head_state: BeaconState<E> = builder
-                    .beacon_client
-                    .get_debug_beacon_states(StateId::Head)
-                    .await
-                    .map_err(|_| reject("couldn't get state"))?
-                    .ok_or_else(|| reject("missing state"))?
-                    .data;
-                let prev_randao = head_state
-                    .get_randao_mix(head_state.current_epoch())
-                    .map_err(|_| reject("couldn't get prev randao"))?;
-
-                let expected_withdrawals = if fork.capella_enabled() {
-                    Some(
-                        builder
-                            .beacon_client
-                            .get_expected_withdrawals(&StateId::Head)
-                            .await
-                            .unwrap()
-                            .data,
-                    )
-                } else {
-                    None
-                };
-
-                let payload_attributes = match fork {
-                    // the withdrawals root is filled in by operations, but we supply the valid withdrawals
-                    // first to avoid polluting the execution block generator with invalid payload attributes
-                    // NOTE: this was part of an effort to add payload attribute uniqueness checks,
-                    // which was abandoned because it broke too many tests in subtle ways.
-                    ForkName::Bellatrix | ForkName::Capella => PayloadAttributes::new(
-                        timestamp,
-                        *prev_randao,
-                        fee_recipient,
-                        expected_withdrawals,
-                        None,
-                    ),
-                    ForkName::Deneb | ForkName::Electra => PayloadAttributes::new(
-                        timestamp,
-                        *prev_randao,
-                        fee_recipient,
-                        expected_withdrawals,
-                        Some(head_block_root),
-                    ),
-                    ForkName::Base | ForkName::Altair => {
-                        return Err(reject("invalid fork"));
-                    }
-                };
-
-                builder
-                    .el
-                    .insert_proposer(slot, head_block_root, val_index, payload_attributes.clone())
-                    .await;
-
-                let forkchoice_update_params = ForkchoiceUpdateParameters {
-                    head_root: Hash256::zero(),
-                    head_hash: None,
-                    justified_hash: Some(justified_execution_hash),
-                    finalized_hash: Some(finalized_execution_hash),
-                };
-
-                let proposer_gas_limit = builder
-                    .val_registration_cache
-                    .read()
-                    .get(&pubkey)
-                    .map(|v| v.message.gas_limit);
-
-                let payload_parameters = PayloadParameters {
-                    parent_hash: head_execution_hash,
-                    parent_gas_limit: head_gas_limit,
-                    proposer_gas_limit,
-                    payload_attributes: &payload_attributes,
-                    forkchoice_update_params: &forkchoice_update_params,
-                    current_fork: fork,
-                };
-
-                let payload_response_type = builder
-                    .el
-                    .get_full_payload_caching(payload_parameters)
-                    .await
-                    .map_err(|_| reject("couldn't get payload"))?;
-
-                let mut message = match payload_response_type {
-                    crate::GetPayloadResponseType::Full(payload_response) => {
-                        #[allow(clippy::type_complexity)]
-                        let (payload, _block_value, maybe_blobs_bundle, _maybe_requests): (
-                            ExecutionPayload<E>,
-                            Uint256,
-                            Option<BlobsBundle<E>>,
-                            Option<ExecutionRequests<E>>,
-                        ) = payload_response.into();
-
-                        match fork {
-                            ForkName::Electra => BuilderBid::Electra(BuilderBidElectra {
-                                header: payload
-                                    .as_electra()
-                                    .map_err(|_| reject("incorrect payload variant"))?
-                                    .into(),
-                                blob_kzg_commitments: maybe_blobs_bundle
-                                    .map(|b| b.commitments)
-                                    .unwrap_or_default(),
-                                value: Uint256::from(DEFAULT_BUILDER_PAYLOAD_VALUE_WEI),
-                                pubkey: builder.builder_sk.public_key().compress(),
-                            }),
-                            ForkName::Deneb => BuilderBid::Deneb(BuilderBidDeneb {
-                                header: payload
-                                    .as_deneb()
-                                    .map_err(|_| reject("incorrect payload variant"))?
-                                    .into(),
-                                blob_kzg_commitments: maybe_blobs_bundle
-                                    .map(|b| b.commitments)
-                                    .unwrap_or_default(),
-                                value: Uint256::from(DEFAULT_BUILDER_PAYLOAD_VALUE_WEI),
-                                pubkey: builder.builder_sk.public_key().compress(),
-                            }),
-                            ForkName::Capella => BuilderBid::Capella(BuilderBidCapella {
-                                header: payload
-                                    .as_capella()
-                                    .map_err(|_| reject("incorrect payload variant"))?
-                                    .into(),
-                                value: Uint256::from(DEFAULT_BUILDER_PAYLOAD_VALUE_WEI),
-                                pubkey: builder.builder_sk.public_key().compress(),
-                            }),
-                            ForkName::Bellatrix => BuilderBid::Bellatrix(BuilderBidBellatrix {
-                                header: payload
-                                    .as_bellatrix()
-                                    .map_err(|_| reject("incorrect payload variant"))?
-                                    .into(),
-                                value: Uint256::from(DEFAULT_BUILDER_PAYLOAD_VALUE_WEI),
-                                pubkey: builder.builder_sk.public_key().compress(),
-                            }),
-                            ForkName::Base | ForkName::Altair => {
-                                return Err(reject("invalid fork"))
-                            }
-                        }
-                    }
-                    crate::GetPayloadResponseType::Blinded(payload_response) => {
-                        #[allow(clippy::type_complexity)]
-                        let (payload, _block_value, maybe_blobs_bundle, _maybe_requests): (
-                            ExecutionPayload<E>,
-                            Uint256,
-                            Option<BlobsBundle<E>>,
-                            Option<ExecutionRequests<E>>,
-                        ) = payload_response.into();
-                        match fork {
-                            ForkName::Electra => BuilderBid::Electra(BuilderBidElectra {
-                                header: payload
-                                    .as_electra()
-                                    .map_err(|_| reject("incorrect payload variant"))?
-                                    .into(),
-                                blob_kzg_commitments: maybe_blobs_bundle
-                                    .map(|b| b.commitments)
-                                    .unwrap_or_default(),
-                                value: Uint256::from(DEFAULT_BUILDER_PAYLOAD_VALUE_WEI),
-                                pubkey: builder.builder_sk.public_key().compress(),
-                            }),
-                            ForkName::Deneb => BuilderBid::Deneb(BuilderBidDeneb {
-                                header: payload
-                                    .as_deneb()
-                                    .map_err(|_| reject("incorrect payload variant"))?
-                                    .into(),
-                                blob_kzg_commitments: maybe_blobs_bundle
-                                    .map(|b| b.commitments)
-                                    .unwrap_or_default(),
-                                value: Uint256::from(DEFAULT_BUILDER_PAYLOAD_VALUE_WEI),
-                                pubkey: builder.builder_sk.public_key().compress(),
-                            }),
-                            ForkName::Capella => BuilderBid::Capella(BuilderBidCapella {
-                                header: payload
-                                    .as_capella()
-                                    .map_err(|_| reject("incorrect payload variant"))?
-                                    .into(),
-                                value: Uint256::from(DEFAULT_BUILDER_PAYLOAD_VALUE_WEI),
-                                pubkey: builder.builder_sk.public_key().compress(),
-                            }),
-                            ForkName::Bellatrix => BuilderBid::Bellatrix(BuilderBidBellatrix {
-                                header: payload
-                                    .as_bellatrix()
-                                    .map_err(|_| reject("incorrect payload variant"))?
-                                    .into(),
-                                value: Uint256::from(DEFAULT_BUILDER_PAYLOAD_VALUE_WEI),
-                                pubkey: builder.builder_sk.public_key().compress(),
-                            }),
-                            ForkName::Base | ForkName::Altair => {
-                                return Err(reject("invalid fork"))
-                            }
-                        }
-                    }
-                };
-
-                builder.apply_operations(&mut message);
-
-                let mut signature =
-                    message.sign_builder_message(&builder.builder_sk, &builder.spec);
-
-                if *builder.invalidate_signatures.read() {
-                    signature = Signature::empty();
-                }
-
-                let fork_name = builder
-                    .spec
-                    .fork_name_at_epoch(slot.epoch(E::slots_per_epoch()));
-                let signed_bid = SignedBuilderBid { message, signature };
                 let resp: ForkVersionedResponse<_> = ForkVersionedResponse {
                     version: Some(fork_name),
                     metadata: Default::default(),
diff --git a/beacon_node/execution_layer/src/test_utils/mock_execution_layer.rs b/beacon_node/execution_layer/src/test_utils/mock_execution_layer.rs
index 48372a39be..f45bfda9ff 100644
--- a/beacon_node/execution_layer/src/test_utils/mock_execution_layer.rs
+++ b/beacon_node/execution_layer/src/test_utils/mock_execution_layer.rs
@@ -13,7 +13,7 @@ pub struct MockExecutionLayer<E: EthSpec> {
     pub server: MockServer<E>,
     pub el: ExecutionLayer<E>,
     pub executor: TaskExecutor,
-    pub spec: ChainSpec,
+    pub spec: Arc<ChainSpec>,
 }
 
 impl<E: EthSpec> MockExecutionLayer<E> {
@@ -28,8 +28,9 @@ impl<E: EthSpec> MockExecutionLayer<E> {
             None,
             None,
             None,
+            None,
             Some(JwtKey::from_slice(&DEFAULT_JWT_SECRET).unwrap()),
-            spec,
+            Arc::new(spec),
             None,
         )
     }
@@ -41,8 +42,9 @@ impl<E: EthSpec> MockExecutionLayer<E> {
         shanghai_time: Option<u64>,
         cancun_time: Option<u64>,
         prague_time: Option<u64>,
+        osaka_time: Option<u64>,
         jwt_key: Option<JwtKey>,
-        spec: ChainSpec,
+        spec: Arc<ChainSpec>,
         kzg: Option<Arc<Kzg>>,
     ) -> Self {
         let handle = executor.handle().unwrap();
@@ -57,6 +59,8 @@ impl<E: EthSpec> MockExecutionLayer<E> {
             shanghai_time,
             cancun_time,
             prague_time,
+            osaka_time,
+            spec.clone(),
             kzg,
         );
 
@@ -318,9 +322,9 @@ impl<E: EthSpec> MockExecutionLayer<E> {
         (self, block_hash)
     }
 
-    pub async fn with_terminal_block<'a, U, V>(self, func: U) -> Self
+    pub async fn with_terminal_block<U, V>(self, func: U) -> Self
     where
-        U: Fn(ChainSpec, ExecutionLayer<E>, Option<ExecutionBlock>) -> V,
+        U: Fn(Arc<ChainSpec>, ExecutionLayer<E>, Option<ExecutionBlock>) -> V,
         V: Future<Output = ()>,
     {
         let terminal_block_number = self
diff --git a/beacon_node/execution_layer/src/test_utils/mod.rs b/beacon_node/execution_layer/src/test_utils/mod.rs
index a390e33d76..c89c1d0533 100644
--- a/beacon_node/execution_layer/src/test_utils/mod.rs
+++ b/beacon_node/execution_layer/src/test_utils/mod.rs
@@ -21,7 +21,7 @@ use std::marker::PhantomData;
 use std::net::{Ipv4Addr, SocketAddr, SocketAddrV4};
 use std::sync::{Arc, LazyLock};
 use tokio::{runtime, sync::oneshot};
-use types::{EthSpec, ExecutionBlockHash, Uint256};
+use types::{ChainSpec, EthSpec, ExecutionBlockHash, Uint256};
 use warp::{http::StatusCode, Filter, Rejection};
 
 use crate::EngineCapabilities;
@@ -44,6 +44,7 @@ pub const DEFAULT_ENGINE_CAPABILITIES: EngineCapabilities = EngineCapabilities {
     new_payload_v2: true,
     new_payload_v3: true,
     new_payload_v4: true,
+    new_payload_v5: true,
     forkchoice_updated_v1: true,
     forkchoice_updated_v2: true,
     forkchoice_updated_v3: true,
@@ -53,6 +54,7 @@ pub const DEFAULT_ENGINE_CAPABILITIES: EngineCapabilities = EngineCapabilities {
     get_payload_v2: true,
     get_payload_v3: true,
     get_payload_v4: true,
+    get_payload_v5: true,
     get_client_version_v1: true,
     get_blobs_v1: true,
     get_inclusion_list_v1: true,
@@ -83,6 +85,7 @@ pub struct MockExecutionConfig {
     pub shanghai_time: Option<u64>,
     pub cancun_time: Option<u64>,
     pub prague_time: Option<u64>,
+    pub osaka_time: Option<u64>,
 }
 
 impl Default for MockExecutionConfig {
@@ -96,6 +99,7 @@ impl Default for MockExecutionConfig {
             shanghai_time: None,
             cancun_time: None,
             prague_time: None,
+            osaka_time: None,
         }
     }
 }
@@ -108,7 +112,7 @@ pub struct MockServer<E: EthSpec> {
 }
 
 impl<E: EthSpec> MockServer<E> {
-    pub fn unit_testing() -> Self {
+    pub fn unit_testing(chain_spec: Arc<ChainSpec>) -> Self {
         Self::new(
             &runtime::Handle::current(),
             JwtKey::from_slice(&DEFAULT_JWT_SECRET).unwrap(),
@@ -118,6 +122,8 @@ impl<E: EthSpec> MockServer<E> {
             None, // FIXME(capella): should this be the default?
             None, // FIXME(deneb): should this be the default?
             None, // FIXME(electra): should this be the default?
+            None, // FIXME(fulu): should this be the default?
+            chain_spec,
             None,
         )
     }
@@ -125,6 +131,7 @@ impl<E: EthSpec> MockServer<E> {
     pub fn new_with_config(
         handle: &runtime::Handle,
         config: MockExecutionConfig,
+        spec: Arc<ChainSpec>,
         kzg: Option<Arc<Kzg>>,
     ) -> Self {
         let MockExecutionConfig {
@@ -136,6 +143,7 @@ impl<E: EthSpec> MockServer<E> {
             shanghai_time,
             cancun_time,
             prague_time,
+            osaka_time,
         } = config;
         let last_echo_request = Arc::new(RwLock::new(None));
         let preloaded_responses = Arc::new(Mutex::new(vec![]));
@@ -146,6 +154,8 @@ impl<E: EthSpec> MockServer<E> {
             shanghai_time,
             cancun_time,
             prague_time,
+            osaka_time,
+            spec,
             kzg,
         );
 
@@ -209,6 +219,8 @@ impl<E: EthSpec> MockServer<E> {
         shanghai_time: Option<u64>,
         cancun_time: Option<u64>,
         prague_time: Option<u64>,
+        osaka_time: Option<u64>,
+        spec: Arc<ChainSpec>,
         kzg: Option<Arc<Kzg>>,
     ) -> Self {
         Self::new_with_config(
@@ -222,7 +234,9 @@ impl<E: EthSpec> MockServer<E> {
                 shanghai_time,
                 cancun_time,
                 prague_time,
+                osaka_time,
             },
+            spec,
             kzg,
         )
     }
diff --git a/beacon_node/genesis/Cargo.toml b/beacon_node/genesis/Cargo.toml
index b01e6a6aea..eeca393947 100644
--- a/beacon_node/genesis/Cargo.toml
+++ b/beacon_node/genesis/Cargo.toml
@@ -9,16 +9,16 @@ eth1_test_rig = { workspace = true }
 sensitive_url = { workspace = true }
 
 [dependencies]
-futures = { workspace = true }
-types = { workspace = true }
 environment = { workspace = true }
 eth1 = { workspace = true }
-rayon = { workspace = true }
-state_processing = { workspace = true }
-merkle_proof = { workspace = true }
-ethereum_ssz = { workspace = true }
 ethereum_hashing = { workspace = true }
-tree_hash = { workspace = true }
-tokio = { workspace = true }
-slog = { workspace = true }
+ethereum_ssz = { workspace = true }
+futures = { workspace = true }
 int_to_bytes = { workspace = true }
+merkle_proof = { workspace = true }
+rayon = { workspace = true }
+slog = { workspace = true }
+state_processing = { workspace = true }
+tokio = { workspace = true }
+tree_hash = { workspace = true }
+types = { workspace = true }
diff --git a/beacon_node/genesis/src/eth1_genesis_service.rs b/beacon_node/genesis/src/eth1_genesis_service.rs
index 3981833a5c..b5f4bd50ee 100644
--- a/beacon_node/genesis/src/eth1_genesis_service.rs
+++ b/beacon_node/genesis/src/eth1_genesis_service.rs
@@ -270,7 +270,7 @@ impl Eth1GenesisService {
 
             // Ignore any block that has already been processed or update the highest processed
             // block.
-            if highest_processed_block.map_or(false, |highest| highest >= block.number) {
+            if highest_processed_block.is_some_and(|highest| highest >= block.number) {
                 continue;
             } else {
                 self.stats
diff --git a/beacon_node/http_api/Cargo.toml b/beacon_node/http_api/Cargo.toml
index 5d601008bc..2fb3ec06bf 100644
--- a/beacon_node/http_api/Cargo.toml
+++ b/beacon_node/http_api/Cargo.toml
@@ -11,12 +11,14 @@ beacon_processor = { workspace = true }
 bs58 = "0.4.0"
 bytes = { workspace = true }
 directory = { workspace = true }
+either = { workspace = true }
 eth1 = { workspace = true }
 eth2 = { workspace = true }
 ethereum_serde_utils = { workspace = true }
 ethereum_ssz = { workspace = true }
 execution_layer = { workspace = true }
 futures = { workspace = true }
+health_metrics = { workspace = true }
 hex = { workspace = true }
 lighthouse_network = { workspace = true }
 lighthouse_version = { workspace = true }
@@ -30,6 +32,7 @@ rand = { workspace = true }
 safe_arith = { workspace = true }
 sensitive_url = { workspace = true }
 serde = { workspace = true }
+serde_json = { workspace = true }
 slog = { workspace = true }
 slot_clock = { workspace = true }
 state_processing = { workspace = true }
diff --git a/beacon_node/http_api/src/attestation_performance.rs b/beacon_node/http_api/src/attestation_performance.rs
index d4f9916814..2f3f340445 100644
--- a/beacon_node/http_api/src/attestation_performance.rs
+++ b/beacon_node/http_api/src/attestation_performance.rs
@@ -7,7 +7,7 @@ use state_processing::{
 };
 use std::sync::Arc;
 use types::{BeaconState, BeaconStateError, EthSpec, Hash256};
-use warp_utils::reject::{beacon_chain_error, custom_bad_request, custom_server_error};
+use warp_utils::reject::{custom_bad_request, custom_server_error, unhandled_error};
 
 const MAX_REQUEST_RANGE_EPOCHS: usize = 100;
 const BLOCK_ROOT_CHUNK_SIZE: usize = 100;
@@ -50,7 +50,7 @@ pub fn get_attestation_performance<T: BeaconChainTypes>(
     let end_slot = end_epoch.end_slot(T::EthSpec::slots_per_epoch());
 
     // Ensure end_epoch is smaller than the current epoch - 1.
-    let current_epoch = chain.epoch().map_err(beacon_chain_error)?;
+    let current_epoch = chain.epoch().map_err(unhandled_error)?;
     if query.end_epoch >= current_epoch - 1 {
         return Err(custom_bad_request(format!(
             "end_epoch must be less than the current epoch - 1. current: {}, end: {}",
@@ -83,7 +83,7 @@ pub fn get_attestation_performance<T: BeaconChainTypes>(
     let index_range = if target.to_lowercase() == "global" {
         chain
             .with_head(|head| Ok((0..head.beacon_state.validators().len() as u64).collect()))
-            .map_err(beacon_chain_error)?
+            .map_err(unhandled_error::<BeaconChainError>)?
     } else {
         vec![target.parse::<u64>().map_err(|_| {
             custom_bad_request(format!(
@@ -96,10 +96,10 @@ pub fn get_attestation_performance<T: BeaconChainTypes>(
     // Load block roots.
     let mut block_roots: Vec<Hash256> = chain
         .forwards_iter_block_roots_until(start_slot, end_slot)
-        .map_err(beacon_chain_error)?
+        .map_err(unhandled_error)?
         .map(|res| res.map(|(root, _)| root))
         .collect::<Result<Vec<Hash256>, _>>()
-        .map_err(beacon_chain_error)?;
+        .map_err(unhandled_error)?;
     block_roots.dedup();
 
     // Load first block so we can get its parent.
@@ -113,7 +113,7 @@ pub fn get_attestation_performance<T: BeaconChainTypes>(
         .and_then(|maybe_block| {
             maybe_block.ok_or(BeaconChainError::MissingBeaconBlock(*first_block_root))
         })
-        .map_err(beacon_chain_error)?;
+        .map_err(unhandled_error)?;
 
     // Load the block of the prior slot which will be used to build the starting state.
     let prior_block = chain
@@ -122,14 +122,14 @@ pub fn get_attestation_performance<T: BeaconChainTypes>(
             maybe_block
                 .ok_or_else(|| BeaconChainError::MissingBeaconBlock(first_block.parent_root()))
         })
-        .map_err(beacon_chain_error)?;
+        .map_err(unhandled_error)?;
 
     // Load state for block replay.
     let state_root = prior_block.state_root();
     let state = chain
         .get_state(&state_root, Some(prior_slot))
         .and_then(|maybe_state| maybe_state.ok_or(BeaconChainError::MissingBeaconState(state_root)))
-        .map_err(beacon_chain_error)?;
+        .map_err(unhandled_error)?;
 
     // Allocate an AttestationPerformance vector for each validator in the range.
     let mut perfs: Vec<AttestationPerformance> =
@@ -198,7 +198,7 @@ pub fn get_attestation_performance<T: BeaconChainTypes>(
                     .and_then(|maybe_block| {
                         maybe_block.ok_or(BeaconChainError::MissingBeaconBlock(*root))
                     })
-                    .map_err(beacon_chain_error)
+                    .map_err(unhandled_error)
             })
             .collect::<Result<Vec<_>, _>>()?;
 
diff --git a/beacon_node/http_api/src/attester_duties.rs b/beacon_node/http_api/src/attester_duties.rs
index 6c7dc3348c..8905b24cde 100644
--- a/beacon_node/http_api/src/attester_duties.rs
+++ b/beacon_node/http_api/src/attester_duties.rs
@@ -16,9 +16,7 @@ pub fn attester_duties<T: BeaconChainTypes>(
     request_indices: &[u64],
     chain: &BeaconChain<T>,
 ) -> Result<ApiDuties, warp::reject::Rejection> {
-    let current_epoch = chain
-        .epoch()
-        .map_err(warp_utils::reject::beacon_chain_error)?;
+    let current_epoch = chain.epoch().map_err(warp_utils::reject::unhandled_error)?;
 
     // Determine what the current epoch would be if we fast-forward our system clock by
     // `MAXIMUM_GOSSIP_CLOCK_DISPARITY`.
@@ -57,7 +55,7 @@ fn cached_attestation_duties<T: BeaconChainTypes>(
 
     let (duties, dependent_root, execution_status) = chain
         .validator_attestation_duties(request_indices, request_epoch, head_block_root)
-        .map_err(warp_utils::reject::beacon_chain_error)?;
+        .map_err(warp_utils::reject::unhandled_error)?;
 
     convert_to_api_response(
         duties,
@@ -82,7 +80,7 @@ fn compute_historic_attester_duties<T: BeaconChainTypes>(
         let (cached_head, execution_status) = chain
             .canonical_head
             .head_and_execution_status()
-            .map_err(warp_utils::reject::beacon_chain_error)?;
+            .map_err(warp_utils::reject::unhandled_error)?;
         let head = &cached_head.snapshot;
 
         if head.beacon_state.current_epoch() <= request_epoch {
@@ -131,13 +129,13 @@ fn compute_historic_attester_duties<T: BeaconChainTypes>(
     state
         .build_committee_cache(relative_epoch, &chain.spec)
         .map_err(BeaconChainError::from)
-        .map_err(warp_utils::reject::beacon_chain_error)?;
+        .map_err(warp_utils::reject::unhandled_error)?;
 
     let dependent_root = state
         // The only block which decides its own shuffling is the genesis block.
         .attester_shuffling_decision_root(chain.genesis_block_root, relative_epoch)
         .map_err(BeaconChainError::from)
-        .map_err(warp_utils::reject::beacon_chain_error)?;
+        .map_err(warp_utils::reject::unhandled_error)?;
 
     let duties = request_indices
         .iter()
@@ -147,7 +145,7 @@ fn compute_historic_attester_duties<T: BeaconChainTypes>(
                 .map_err(BeaconChainError::from)
         })
         .collect::<Result<_, _>>()
-        .map_err(warp_utils::reject::beacon_chain_error)?;
+        .map_err(warp_utils::reject::unhandled_error)?;
 
     convert_to_api_response(
         duties,
@@ -181,7 +179,7 @@ fn ensure_state_knows_attester_duties_for_epoch<E: EthSpec>(
         // A "partial" state advance is adequate since attester duties don't rely on state roots.
         partial_state_advance(state, Some(state_root), target_slot, spec)
             .map_err(BeaconChainError::from)
-            .map_err(warp_utils::reject::beacon_chain_error)?;
+            .map_err(warp_utils::reject::unhandled_error)?;
     }
 
     Ok(())
@@ -208,7 +206,7 @@ fn convert_to_api_response<T: BeaconChainTypes>(
     let usize_indices = indices.iter().map(|i| *i as usize).collect::<Vec<_>>();
     let index_to_pubkey_map = chain
         .validator_pubkey_bytes_many(&usize_indices)
-        .map_err(warp_utils::reject::beacon_chain_error)?;
+        .map_err(warp_utils::reject::unhandled_error)?;
 
     let data = duties
         .into_iter()
diff --git a/beacon_node/http_api/src/block_id.rs b/beacon_node/http_api/src/block_id.rs
index dba8eb1ef3..cdef1521ec 100644
--- a/beacon_node/http_api/src/block_id.rs
+++ b/beacon_node/http_api/src/block_id.rs
@@ -1,4 +1,5 @@
 use crate::{state_id::checkpoint_slot_and_execution_optimistic, ExecutionOptimistic};
+use beacon_chain::kzg_utils::reconstruct_blobs;
 use beacon_chain::{BeaconChain, BeaconChainError, BeaconChainTypes, WhenSlotSkipped};
 use eth2::types::BlobIndicesQuery;
 use eth2::types::BlockId as CoreBlockId;
@@ -9,6 +10,7 @@ use types::{
     BlobSidecarList, EthSpec, FixedBytesExtended, Hash256, SignedBeaconBlock,
     SignedBlindedBeaconBlock, Slot,
 };
+use warp::Rejection;
 
 /// Wraps `eth2::types::BlockId` and provides a simple way to obtain a block or root for a given
 /// `BlockId`.
@@ -36,7 +38,7 @@ impl BlockId {
                 let (cached_head, execution_status) = chain
                     .canonical_head
                     .head_and_execution_status()
-                    .map_err(warp_utils::reject::beacon_chain_error)?;
+                    .map_err(warp_utils::reject::unhandled_error)?;
                 Ok((
                     cached_head.head_block_root(),
                     execution_status.is_optimistic_or_invalid(),
@@ -61,10 +63,10 @@ impl BlockId {
             CoreBlockId::Slot(slot) => {
                 let execution_optimistic = chain
                     .is_optimistic_or_invalid_head()
-                    .map_err(warp_utils::reject::beacon_chain_error)?;
+                    .map_err(warp_utils::reject::unhandled_error)?;
                 let root = chain
                     .block_root_at_slot(*slot, WhenSlotSkipped::None)
-                    .map_err(warp_utils::reject::beacon_chain_error)
+                    .map_err(warp_utils::reject::unhandled_error)
                     .and_then(|root_opt| {
                         root_opt.ok_or_else(|| {
                             warp_utils::reject::custom_not_found(format!(
@@ -94,17 +96,17 @@ impl BlockId {
                     .store
                     .block_exists(root)
                     .map_err(BeaconChainError::DBError)
-                    .map_err(warp_utils::reject::beacon_chain_error)?
+                    .map_err(warp_utils::reject::unhandled_error)?
                 {
                     let execution_optimistic = chain
                         .canonical_head
                         .fork_choice_read_lock()
                         .is_optimistic_or_invalid_block(root)
                         .map_err(BeaconChainError::ForkChoiceError)
-                        .map_err(warp_utils::reject::beacon_chain_error)?;
+                        .map_err(warp_utils::reject::unhandled_error)?;
                     let blinded_block = chain
                         .get_blinded_block(root)
-                        .map_err(warp_utils::reject::beacon_chain_error)?
+                        .map_err(warp_utils::reject::unhandled_error)?
                         .ok_or_else(|| {
                             warp_utils::reject::custom_not_found(format!(
                                 "beacon block with root {}",
@@ -114,7 +116,7 @@ impl BlockId {
                     let block_slot = blinded_block.slot();
                     let finalized = chain
                         .is_finalized_block(root, block_slot)
-                        .map_err(warp_utils::reject::beacon_chain_error)?;
+                        .map_err(warp_utils::reject::unhandled_error)?;
                     Ok((*root, execution_optimistic, finalized))
                 } else {
                     Err(warp_utils::reject::custom_not_found(format!(
@@ -132,7 +134,7 @@ impl BlockId {
     ) -> Result<Option<SignedBlindedBeaconBlock<T::EthSpec>>, warp::Rejection> {
         chain
             .get_blinded_block(root)
-            .map_err(warp_utils::reject::beacon_chain_error)
+            .map_err(warp_utils::reject::unhandled_error)
     }
 
     /// Return the `SignedBeaconBlock` identified by `self`.
@@ -152,7 +154,7 @@ impl BlockId {
                 let (cached_head, execution_status) = chain
                     .canonical_head
                     .head_and_execution_status()
-                    .map_err(warp_utils::reject::beacon_chain_error)?;
+                    .map_err(warp_utils::reject::unhandled_error)?;
                 Ok((
                     cached_head.snapshot.beacon_block.clone_as_blinded(),
                     execution_status.is_optimistic_or_invalid(),
@@ -209,7 +211,7 @@ impl BlockId {
                 let (cached_head, execution_status) = chain
                     .canonical_head
                     .head_and_execution_status()
-                    .map_err(warp_utils::reject::beacon_chain_error)?;
+                    .map_err(warp_utils::reject::unhandled_error)?;
                 Ok((
                     cached_head.snapshot.beacon_block.clone(),
                     execution_status.is_optimistic_or_invalid(),
@@ -221,7 +223,7 @@ impl BlockId {
                 chain
                     .get_block(&root)
                     .await
-                    .map_err(warp_utils::reject::beacon_chain_error)
+                    .map_err(warp_utils::reject::unhandled_error)
                     .and_then(|block_opt| match block_opt {
                         Some(block) => {
                             if block.slot() != *slot {
@@ -243,7 +245,7 @@ impl BlockId {
                 chain
                     .get_block(&root)
                     .await
-                    .map_err(warp_utils::reject::beacon_chain_error)
+                    .map_err(warp_utils::reject::unhandled_error)
                     .and_then(|block_opt| {
                         block_opt
                             .map(|block| (Arc::new(block), execution_optimistic, finalized))
@@ -261,7 +263,7 @@ impl BlockId {
     #[allow(clippy::type_complexity)]
     pub fn get_blinded_block_and_blob_list_filtered<T: BeaconChainTypes>(
         &self,
-        indices: BlobIndicesQuery,
+        query: BlobIndicesQuery,
         chain: &BeaconChain<T>,
     ) -> Result<
         (
@@ -285,37 +287,92 @@ impl BlockId {
         })?;
 
         // Return the `BlobSidecarList` identified by `self`.
+        let max_blobs_per_block = chain.spec.max_blobs_per_block(block.epoch()) as usize;
         let blob_sidecar_list = if !blob_kzg_commitments.is_empty() {
-            chain
-                .store
-                .get_blobs(&root)
-                .map_err(|e| warp_utils::reject::beacon_chain_error(e.into()))?
-                .ok_or_else(|| {
-                    warp_utils::reject::custom_not_found(format!(
-                        "no blobs stored for block {root}"
-                    ))
-                })?
+            if chain.spec.is_peer_das_enabled_for_epoch(block.epoch()) {
+                Self::get_blobs_from_data_columns(chain, root, query.indices, &block)?
+            } else {
+                Self::get_blobs(chain, root, query.indices, max_blobs_per_block)?
+            }
         } else {
-            BlobSidecarList::default()
+            BlobSidecarList::new(vec![], max_blobs_per_block)
+                .map_err(|e| warp_utils::reject::custom_server_error(format!("{:?}", e)))?
         };
 
-        let blob_sidecar_list_filtered = match indices.indices {
+        Ok((block, blob_sidecar_list, execution_optimistic, finalized))
+    }
+
+    fn get_blobs<T: BeaconChainTypes>(
+        chain: &BeaconChain<T>,
+        root: Hash256,
+        indices: Option<Vec<u64>>,
+        max_blobs_per_block: usize,
+    ) -> Result<BlobSidecarList<T::EthSpec>, Rejection> {
+        let blob_sidecar_list = chain
+            .store
+            .get_blobs(&root)
+            .map_err(|e| warp_utils::reject::unhandled_error(BeaconChainError::from(e)))?
+            .blobs()
+            .ok_or_else(|| {
+                warp_utils::reject::custom_not_found(format!("no blobs stored for block {root}"))
+            })?;
+
+        let blob_sidecar_list_filtered = match indices {
             Some(vec) => {
-                let list = blob_sidecar_list
+                let list: Vec<_> = blob_sidecar_list
                     .into_iter()
                     .filter(|blob_sidecar| vec.contains(&blob_sidecar.index))
                     .collect();
-                BlobSidecarList::new(list)
+
+                BlobSidecarList::new(list, max_blobs_per_block)
                     .map_err(|e| warp_utils::reject::custom_server_error(format!("{:?}", e)))?
             }
             None => blob_sidecar_list,
         };
-        Ok((
-            block,
-            blob_sidecar_list_filtered,
-            execution_optimistic,
-            finalized,
-        ))
+
+        Ok(blob_sidecar_list_filtered)
+    }
+
+    fn get_blobs_from_data_columns<T: BeaconChainTypes>(
+        chain: &BeaconChain<T>,
+        root: Hash256,
+        blob_indices: Option<Vec<u64>>,
+        block: &SignedBlindedBeaconBlock<<T as BeaconChainTypes>::EthSpec>,
+    ) -> Result<BlobSidecarList<T::EthSpec>, Rejection> {
+        let column_indices = chain.store.get_data_column_keys(root).map_err(|e| {
+            warp_utils::reject::custom_server_error(format!(
+                "Error fetching data columns keys: {e:?}"
+            ))
+        })?;
+
+        let num_found_column_keys = column_indices.len();
+        let num_required_columns = chain.spec.number_of_columns / 2;
+        let is_blob_available = num_found_column_keys >= num_required_columns as usize;
+
+        if is_blob_available {
+            let data_columns = column_indices
+                .into_iter()
+                .filter_map(
+                    |column_index| match chain.get_data_column(&root, &column_index) {
+                        Ok(Some(data_column)) => Some(Ok(data_column)),
+                        Ok(None) => None,
+                        Err(e) => Some(Err(warp_utils::reject::unhandled_error(e))),
+                    },
+                )
+                .collect::<Result<Vec<_>, _>>()?;
+
+            reconstruct_blobs(&chain.kzg, &data_columns, blob_indices, block, &chain.spec).map_err(
+                |e| {
+                    warp_utils::reject::custom_server_error(format!(
+                        "Error reconstructing data columns: {e:?}"
+                    ))
+                },
+            )
+        } else {
+            Err(warp_utils::reject::custom_server_error(
+                format!("Insufficient data columns to reconstruct blobs: required {num_required_columns}, but only {num_found_column_keys} were found.")
+            ))
+        }
     }
 }
 
diff --git a/beacon_node/http_api/src/block_packing_efficiency.rs b/beacon_node/http_api/src/block_packing_efficiency.rs
index 66c7187278..431547f10b 100644
--- a/beacon_node/http_api/src/block_packing_efficiency.rs
+++ b/beacon_node/http_api/src/block_packing_efficiency.rs
@@ -13,7 +13,7 @@ use types::{
     AttestationRef, BeaconCommittee, BeaconState, BeaconStateError, BlindedPayload, ChainSpec,
     Epoch, EthSpec, Hash256, OwnedBeaconCommittee, RelativeEpoch, SignedBeaconBlock, Slot,
 };
-use warp_utils::reject::{beacon_chain_error, custom_bad_request, custom_server_error};
+use warp_utils::reject::{custom_bad_request, custom_server_error, unhandled_error};
 
 /// Load blocks from block roots in chunks to reduce load on memory.
 const BLOCK_ROOT_CHUNK_SIZE: usize = 100;
@@ -263,9 +263,9 @@ pub fn get_block_packing_efficiency<T: BeaconChainTypes>(
     // Load block roots.
     let mut block_roots: Vec<Hash256> = chain
         .forwards_iter_block_roots_until(start_slot_of_prior_epoch, end_slot)
-        .map_err(beacon_chain_error)?
+        .map_err(unhandled_error)?
         .collect::<Result<Vec<(Hash256, Slot)>, _>>()
-        .map_err(beacon_chain_error)?
+        .map_err(unhandled_error)?
         .iter()
         .map(|(root, _)| *root)
         .collect();
@@ -280,7 +280,7 @@ pub fn get_block_packing_efficiency<T: BeaconChainTypes>(
         .and_then(|maybe_block| {
             maybe_block.ok_or(BeaconChainError::MissingBeaconBlock(*first_block_root))
         })
-        .map_err(beacon_chain_error)?;
+        .map_err(unhandled_error)?;
 
     // Load state for block replay.
     let starting_state_root = first_block.state_root();
@@ -290,7 +290,7 @@ pub fn get_block_packing_efficiency<T: BeaconChainTypes>(
         .and_then(|maybe_state| {
             maybe_state.ok_or(BeaconChainError::MissingBeaconState(starting_state_root))
         })
-        .map_err(beacon_chain_error)?;
+        .map_err(unhandled_error)?;
 
     // Initialize response vector.
     let mut response = Vec::new();
@@ -392,7 +392,7 @@ pub fn get_block_packing_efficiency<T: BeaconChainTypes>(
                     .and_then(|maybe_block| {
                         maybe_block.ok_or(BeaconChainError::MissingBeaconBlock(*root))
                     })
-                    .map_err(beacon_chain_error)
+                    .map_err(unhandled_error)
             })
             .collect::<Result<Vec<_>, _>>()?;
 
diff --git a/beacon_node/http_api/src/block_rewards.rs b/beacon_node/http_api/src/block_rewards.rs
index ad71e9e9d0..0cc878bb48 100644
--- a/beacon_node/http_api/src/block_rewards.rs
+++ b/beacon_node/http_api/src/block_rewards.rs
@@ -7,7 +7,7 @@ use std::num::NonZeroUsize;
 use std::sync::Arc;
 use types::beacon_block::BlindedBeaconBlock;
 use types::non_zero_usize::new_non_zero_usize;
-use warp_utils::reject::{beacon_chain_error, beacon_state_error, custom_bad_request};
+use warp_utils::reject::{beacon_state_error, custom_bad_request, unhandled_error};
 
 const STATE_CACHE_SIZE: NonZeroUsize = new_non_zero_usize(2);
 
@@ -30,23 +30,23 @@ pub fn get_block_rewards<T: BeaconChainTypes>(
 
     let end_block_root = chain
         .block_root_at_slot(end_slot, WhenSlotSkipped::Prev)
-        .map_err(beacon_chain_error)?
+        .map_err(unhandled_error)?
         .ok_or_else(|| custom_bad_request(format!("block at end slot {} unknown", end_slot)))?;
 
     let blocks = chain
         .store
         .load_blocks_to_replay(start_slot, end_slot, end_block_root)
-        .map_err(|e| beacon_chain_error(e.into()))?;
+        .map_err(|e| unhandled_error(BeaconChainError::from(e)))?;
 
     let state_root = chain
         .state_root_at_slot(prior_slot)
-        .map_err(beacon_chain_error)?
+        .map_err(unhandled_error)?
         .ok_or_else(|| custom_bad_request(format!("prior state at slot {} unknown", prior_slot)))?;
 
     let mut state = chain
         .get_state(&state_root, Some(prior_slot))
         .and_then(|maybe_state| maybe_state.ok_or(BeaconChainError::MissingBeaconState(state_root)))
-        .map_err(beacon_chain_error)?;
+        .map_err(unhandled_error)?;
 
     state
         .build_caches(&chain.spec)
@@ -73,12 +73,12 @@ pub fn get_block_rewards<T: BeaconChainTypes>(
         .state_root_iter(
             chain
                 .forwards_iter_state_roots_until(prior_slot, end_slot)
-                .map_err(beacon_chain_error)?,
+                .map_err(unhandled_error)?,
         )
         .no_signature_verification()
         .minimal_block_root_verification()
         .apply_blocks(blocks, None)
-        .map_err(beacon_chain_error)?;
+        .map_err(unhandled_error)?;
 
     if block_replayer.state_root_miss() {
         warn!(
@@ -125,7 +125,7 @@ pub fn compute_block_rewards<T: BeaconChainTypes>(
             );
             let parent_block = chain
                 .get_blinded_block(&parent_root)
-                .map_err(beacon_chain_error)?
+                .map_err(unhandled_error)?
                 .ok_or_else(|| {
                     custom_bad_request(format!(
                         "parent block not known or not canonical: {:?}",
@@ -135,7 +135,7 @@ pub fn compute_block_rewards<T: BeaconChainTypes>(
 
             let parent_state = chain
                 .get_state(&parent_block.state_root(), Some(parent_block.slot()))
-                .map_err(beacon_chain_error)?
+                .map_err(unhandled_error)?
                 .ok_or_else(|| {
                     custom_bad_request(format!(
                         "no state known for parent block: {:?}",
@@ -148,7 +148,7 @@ pub fn compute_block_rewards<T: BeaconChainTypes>(
                 .state_root_iter([Ok((parent_block.state_root(), parent_block.slot()))].into_iter())
                 .minimal_block_root_verification()
                 .apply_blocks(vec![], Some(block.slot()))
-                .map_err(beacon_chain_error)?;
+                .map_err(unhandled_error::<BeaconChainError>)?;
 
             if block_replayer.state_root_miss() {
                 warn!(
@@ -176,7 +176,7 @@ pub fn compute_block_rewards<T: BeaconChainTypes>(
                 &mut reward_cache,
                 true,
             )
-            .map_err(beacon_chain_error)?;
+            .map_err(unhandled_error)?;
         block_rewards.push(block_reward);
     }
 
diff --git a/beacon_node/http_api/src/build_block_contents.rs b/beacon_node/http_api/src/build_block_contents.rs
index c2ccb6695e..fb8fba0731 100644
--- a/beacon_node/http_api/src/build_block_contents.rs
+++ b/beacon_node/http_api/src/build_block_contents.rs
@@ -23,7 +23,7 @@ pub fn build_block_contents<E: EthSpec>(
                 } = block;
 
                 let Some((kzg_proofs, blobs)) = blob_items else {
-                    return Err(warp_utils::reject::block_production_error(
+                    return Err(warp_utils::reject::unhandled_error(
                         BlockProductionError::MissingBlobs,
                     ));
                 };
diff --git a/beacon_node/http_api/src/inclusion_list_duties.rs b/beacon_node/http_api/src/inclusion_list_duties.rs
index 745f6b78cc..45e1f782e6 100644
--- a/beacon_node/http_api/src/inclusion_list_duties.rs
+++ b/beacon_node/http_api/src/inclusion_list_duties.rs
@@ -14,7 +14,9 @@ pub fn inclusion_list_duties<T: BeaconChainTypes>(
 ) -> Result<ApiDuties, warp::reject::Rejection> {
     let current_epoch = chain
         .epoch()
-        .map_err(warp_utils::reject::beacon_chain_error)?;
+        // TODO(focil) unwrap
+        .unwrap();
+        // .map_err(warp_utils::reject::beacon_chain_error)?;
 
     // Determine what the current epoch would be if we fast-forward our system clock by
     // `MAXIMUM_GOSSIP_CLOCK_DISPARITY`.
@@ -35,7 +37,9 @@ pub fn inclusion_list_duties<T: BeaconChainTypes>(
         let head_block_root = chain.canonical_head.cached_head().head_block_root();
         let (duties, dependent_root) = chain
             .validator_inclusion_list_duties(request_indices, request_epoch, head_block_root)
-            .map_err(warp_utils::reject::beacon_chain_error)?;
+            // TODO(focil) unwrap
+            .unwrap();
+            //.map_err(warp_utils::reject::beacon_chain_error)?;
         convert_to_api_response(duties, request_indices, dependent_root, chain)
     } else if request_epoch > current_epoch + 1 {
         Err(warp_utils::reject::custom_bad_request(format!(
@@ -73,7 +77,9 @@ fn convert_to_api_response<T: BeaconChainTypes>(
     let usize_indices = indices.iter().map(|i| *i as usize).collect::<Vec<_>>();
     let index_to_pubkey_map = chain
         .validator_pubkey_bytes_many(&usize_indices)
-        .map_err(warp_utils::reject::beacon_chain_error)?;
+        // TODO(focil) unwrap
+        .unwrap();
+        // .map_err(warp_utils::reject::beacon_chain_error)?;
 
     let data = duties
         .into_iter()
diff --git a/beacon_node/http_api/src/lib.rs b/beacon_node/http_api/src/lib.rs
index 1a024135aa..9bd27133b9 100644
--- a/beacon_node/http_api/src/lib.rs
+++ b/beacon_node/http_api/src/lib.rs
@@ -31,7 +31,6 @@ mod validator;
 mod validator_inclusion;
 mod validators;
 mod version;
-
 use crate::light_client::{get_light_client_bootstrap, get_light_client_updates};
 use crate::produce_block::{produce_blinded_block_v2, produce_block_v2, produce_block_v3};
 use crate::version::fork_versioned_response;
@@ -45,12 +44,15 @@ pub use block_id::BlockId;
 use builder_states::get_next_withdrawals;
 use bytes::Bytes;
 use directory::DEFAULT_ROOT_DIR;
+use either::Either;
 use eth2::types::{
     self as api_types, BroadcastValidation, EndpointVersion, ForkChoice, ForkChoiceNode,
     LightClientUpdatesQuery, PublishBlockRequest, ValidatorBalancesRequestBody, ValidatorId,
     ValidatorStatus, ValidatorsRequestBody,
 };
 use eth2::{CONSENSUS_VERSION_HEADER, CONTENT_TYPE_HEADER, SSZ_CONTENT_TYPE_HEADER};
+use health_metrics::observe::Observe;
+use lighthouse_network::rpc::methods::MetaData;
 use lighthouse_network::{types::SyncState, EnrExt, NetworkGlobals, PeerId, PubsubMessage};
 use lighthouse_version::version_with_platform;
 use logging::SSELoggingComponents;
@@ -61,6 +63,7 @@ pub use publish_blocks::{
     publish_blinded_block, publish_block, reconstruct_block, ProvenancedBlock,
 };
 use serde::{Deserialize, Serialize};
+use serde_json::Value;
 use slog::{crit, debug, error, info, warn, Logger};
 use slot_clock::SlotClock;
 use ssz::Encode;
@@ -83,11 +86,11 @@ use tokio_stream::{
 };
 use types::{
     fork_versioned_response::EmptyMetadata, Attestation, AttestationData, AttestationShufflingId,
-    AttesterSlashing, BeaconStateError, CommitteeCache, ConfigAndPreset, Epoch, EthSpec, ForkName,
-    ForkVersionedResponse, Hash256, ProposerPreparationData, ProposerSlashing, RelativeEpoch,
-    SignedAggregateAndProof, SignedBlindedBeaconBlock, SignedBlsToExecutionChange,
-    SignedContributionAndProof, SignedInclusionList, SignedValidatorRegistrationData,
-    SignedVoluntaryExit, Slot, SyncCommitteeMessage, SyncContributionData,
+    AttesterSlashing, BeaconStateError, ChainSpec, CommitteeCache, ConfigAndPreset, Epoch, EthSpec,
+    ForkName, ForkVersionedResponse, Hash256, ProposerPreparationData, ProposerSlashing,
+    RelativeEpoch, SignedAggregateAndProof, SignedBlindedBeaconBlock, SignedBlsToExecutionChange,
+    SignedContributionAndProof, SignedValidatorRegistrationData, SignedVoluntaryExit, Slot,
+    SyncCommitteeMessage, SyncContributionData, SignedInclusionList
 };
 use validator::pubkey_to_validator_index;
 use version::{
@@ -941,9 +944,9 @@ pub fn serve<T: BeaconChainTypes>(
                                                         )
                                                     }
                                                 }
-                                                _ => {
-                                                    warp_utils::reject::beacon_chain_error(e.into())
-                                                }
+                                                _ => warp_utils::reject::unhandled_error(
+                                                    BeaconChainError::from(e),
+                                                ),
                                             }
                                         })?;
 
@@ -1070,7 +1073,7 @@ pub fn serve<T: BeaconChainTypes>(
 
                     let validators = chain
                         .validator_indices(sync_committee.pubkeys.iter())
-                        .map_err(warp_utils::reject::beacon_chain_error)?;
+                        .map_err(warp_utils::reject::unhandled_error)?;
 
                     let validator_aggregates = validators
                         .chunks_exact(T::EthSpec::sync_subcommittee_size())
@@ -1150,7 +1153,7 @@ pub fn serve<T: BeaconChainTypes>(
                                 let (cached_head, execution_status) = chain
                                     .canonical_head
                                     .head_and_execution_status()
-                                    .map_err(warp_utils::reject::beacon_chain_error)?;
+                                    .map_err(warp_utils::reject::unhandled_error)?;
                                 (
                                     cached_head.head_block_root(),
                                     cached_head.snapshot.beacon_block.clone_as_blinded(),
@@ -1164,13 +1167,13 @@ pub fn serve<T: BeaconChainTypes>(
                                     BlockId::from_root(parent_root).blinded_block(&chain)?;
                                 let (root, _slot) = chain
                                     .forwards_iter_block_roots(parent.slot())
-                                    .map_err(warp_utils::reject::beacon_chain_error)?
+                                    .map_err(warp_utils::reject::unhandled_error)?
                                     // Ignore any skip-slots immediately following the parent.
                                     .find(|res| {
-                                        res.as_ref().map_or(false, |(root, _)| *root != parent_root)
+                                        res.as_ref().is_ok_and(|(root, _)| *root != parent_root)
                                     })
                                     .transpose()
-                                    .map_err(warp_utils::reject::beacon_chain_error)?
+                                    .map_err(warp_utils::reject::unhandled_error)?
                                     .ok_or_else(|| {
                                         warp_utils::reject::custom_not_found(format!(
                                             "child of block with root {}",
@@ -1251,8 +1254,8 @@ pub fn serve<T: BeaconChainTypes>(
 
                     let canonical = chain
                         .block_root_at_slot(block.slot(), WhenSlotSkipped::None)
-                        .map_err(warp_utils::reject::beacon_chain_error)?
-                        .map_or(false, |canonical| root == canonical);
+                        .map_err(warp_utils::reject::unhandled_error)?
+                        .is_some_and(|canonical| root == canonical);
 
                     let data = api_types::BlockHeaderData {
                         root,
@@ -1278,6 +1281,9 @@ pub fn serve<T: BeaconChainTypes>(
     let consensus_version_header_filter =
         warp::header::header::<ForkName>(CONSENSUS_VERSION_HEADER);
 
+    let optional_consensus_version_header_filter =
+        warp::header::optional::<ForkName>(CONSENSUS_VERSION_HEADER);
+
     // POST beacon/blocks
     let post_beacon_blocks = eth_v1
         .and(warp::path("beacon"))
@@ -1828,32 +1834,86 @@ pub fn serve<T: BeaconChainTypes>(
         .and(task_spawner_filter.clone())
         .and(chain_filter.clone());
 
+    let beacon_pool_path_v2 = eth_v2
+        .and(warp::path("beacon"))
+        .and(warp::path("pool"))
+        .and(task_spawner_filter.clone())
+        .and(chain_filter.clone());
+
     let beacon_pool_path_any = any_version
         .and(warp::path("beacon"))
         .and(warp::path("pool"))
         .and(task_spawner_filter.clone())
         .and(chain_filter.clone());
 
-    // POST beacon/pool/attestations
-    let post_beacon_pool_attestations = beacon_pool_path_any
+    let post_beacon_pool_attestations_v1 = beacon_pool_path
         .clone()
         .and(warp::path("attestations"))
         .and(warp::path::end())
         .and(warp_utils::json::json())
         .and(network_tx_filter.clone())
-        .and(reprocess_send_filter)
+        .and(reprocess_send_filter.clone())
         .and(log_filter.clone())
         .then(
-            // V1 and V2 are identical except V2 has a consensus version header in the request.
-            // We only require this header for SSZ deserialization, which isn't supported for
-            // this endpoint presently.
-            |_endpoint_version: EndpointVersion,
-             task_spawner: TaskSpawner<T::EthSpec>,
+            |task_spawner: TaskSpawner<T::EthSpec>,
              chain: Arc<BeaconChain<T>>,
              attestations: Vec<Attestation<T::EthSpec>>,
              network_tx: UnboundedSender<NetworkMessage<T::EthSpec>>,
              reprocess_tx: Option<Sender<ReprocessQueueMessage>>,
              log: Logger| async move {
+                let attestations = attestations.into_iter().map(Either::Left).collect();
+                let result = crate::publish_attestations::publish_attestations(
+                    task_spawner,
+                    chain,
+                    attestations,
+                    network_tx,
+                    reprocess_tx,
+                    log,
+                )
+                .await
+                .map(|()| warp::reply::json(&()));
+                convert_rejection(result).await
+            },
+        );
+
+    let post_beacon_pool_attestations_v2 = beacon_pool_path_v2
+        .clone()
+        .and(warp::path("attestations"))
+        .and(warp::path::end())
+        .and(warp_utils::json::json::<Value>())
+        .and(optional_consensus_version_header_filter)
+        .and(network_tx_filter.clone())
+        .and(reprocess_send_filter.clone())
+        .and(log_filter.clone())
+        .then(
+            |task_spawner: TaskSpawner<T::EthSpec>,
+             chain: Arc<BeaconChain<T>>,
+             payload: Value,
+             fork_name: Option<ForkName>,
+             network_tx: UnboundedSender<NetworkMessage<T::EthSpec>>,
+             reprocess_tx: Option<Sender<ReprocessQueueMessage>>,
+             log: Logger| async move {
+                let attestations =
+                    match crate::publish_attestations::deserialize_attestation_payload::<T>(
+                        payload, fork_name, &log,
+                    ) {
+                        Ok(attestations) => attestations,
+                        Err(err) => {
+                            warn!(
+                                log,
+                                "Unable to deserialize attestation POST request";
+                                "error" => ?err
+                            );
+                            return warp::reply::with_status(
+                                warp::reply::json(
+                                    &"Unable to deserialize request body".to_string(),
+                                ),
+                                eth2::StatusCode::BAD_REQUEST,
+                            )
+                            .into_response();
+                        }
+                    };
+
                 let result = crate::publish_attestations::publish_attestations(
                     task_spawner,
                     chain,
@@ -2891,36 +2951,24 @@ pub fn serve<T: BeaconChainTypes>(
         .and(warp::path::end())
         .and(task_spawner_filter.clone())
         .and(network_globals.clone())
+        .and(chain_filter.clone())
         .then(
             |task_spawner: TaskSpawner<T::EthSpec>,
-             network_globals: Arc<NetworkGlobals<T::EthSpec>>| {
+             network_globals: Arc<NetworkGlobals<T::EthSpec>>,
+             chain: Arc<BeaconChain<T>>| {
                 task_spawner.blocking_json_task(Priority::P1, move || {
                     let enr = network_globals.local_enr();
                     let p2p_addresses = enr.multiaddr_p2p_tcp();
                     let discovery_addresses = enr.multiaddr_p2p_udp();
-                    let meta_data = network_globals.local_metadata.read();
                     Ok(api_types::GenericResponse::from(api_types::IdentityData {
                         peer_id: network_globals.local_peer_id().to_base58(),
                         enr,
                         p2p_addresses,
                         discovery_addresses,
-                        metadata: api_types::MetaData {
-                            seq_number: *meta_data.seq_number(),
-                            attnets: format!(
-                                "0x{}",
-                                hex::encode(meta_data.attnets().clone().into_bytes()),
-                            ),
-                            syncnets: format!(
-                                "0x{}",
-                                hex::encode(
-                                    meta_data
-                                        .syncnets()
-                                        .cloned()
-                                        .unwrap_or_default()
-                                        .into_bytes()
-                                )
-                            ),
-                        },
+                        metadata: from_meta_data::<T::EthSpec>(
+                            &network_globals.local_metadata,
+                            &chain.spec,
+                        ),
                     }))
                 })
             },
@@ -2963,7 +3011,7 @@ pub fn serve<T: BeaconChainTypes>(
                             let (head, head_execution_status) = chain
                                 .canonical_head
                                 .head_and_execution_status()
-                                .map_err(warp_utils::reject::beacon_chain_error)?;
+                                .map_err(warp_utils::reject::unhandled_error)?;
                             let head_slot = head.head_slot();
                             let current_slot =
                                 chain.slot_clock.now_or_genesis().ok_or_else(|| {
@@ -3023,7 +3071,7 @@ pub fn serve<T: BeaconChainTypes>(
                         .blocking_response_task(Priority::P0, move || {
                             let is_optimistic = chain
                                 .is_optimistic_or_invalid_head()
-                                .map_err(warp_utils::reject::beacon_chain_error)?;
+                                .map_err(warp_utils::reject::unhandled_error)?;
 
                             let is_syncing = !network_globals.sync_state.read().is_synced();
 
@@ -3333,9 +3381,7 @@ pub fn serve<T: BeaconChainTypes>(
                 task_spawner.blocking_json_task(Priority::P0, move || {
                     not_synced_filter?;
 
-                    let current_slot = chain
-                        .slot()
-                        .map_err(warp_utils::reject::beacon_chain_error)?;
+                    let current_slot = chain.slot().map_err(warp_utils::reject::unhandled_error)?;
 
                     // allow a tolerance of one slot to account for clock skew
                     if query.slot > current_slot + 1 {
@@ -3349,7 +3395,7 @@ pub fn serve<T: BeaconChainTypes>(
                         .produce_unaggregated_attestation(query.slot, query.committee_index)
                         .map(|attestation| attestation.data().clone())
                         .map(api_types::GenericResponse::from)
-                        .map_err(warp_utils::reject::beacon_chain_error)
+                        .map_err(warp_utils::reject::unhandled_error)
                 })
             },
         );
@@ -3544,7 +3590,9 @@ pub fn serve<T: BeaconChainTypes>(
 
                     let current_slot = chain
                         .slot()
-                        .map_err(warp_utils::reject::beacon_chain_error)?;
+                        .unwrap();
+                        // TODO(focil) unwrap
+                        // .map_err(warp_utils::reject::beacon_chain_error)?;
 
                     // allow a tolerance of one slot to account for clock skew
                     //
@@ -3560,7 +3608,9 @@ pub fn serve<T: BeaconChainTypes>(
                         .produce_inclusion_list(query.slot)
                         .await
                         .map(api_types::GenericResponse::from)
-                        .map_err(warp_utils::reject::beacon_chain_error)?;
+                        // TODO(focil) unwrap
+                        .unwrap();
+                        // .map_err(warp_utils::reject::beacon_chain_error)?;
                     Ok::<_, warp::reject::Rejection>(warp::reply::json(&data).into_response())
                 })
             },
@@ -3789,11 +3839,9 @@ pub fn serve<T: BeaconChainTypes>(
                         .execution_layer
                         .as_ref()
                         .ok_or(BeaconChainError::ExecutionLayerMissing)
-                        .map_err(warp_utils::reject::beacon_chain_error)?;
+                        .map_err(warp_utils::reject::unhandled_error)?;
 
-                    let current_slot = chain
-                        .slot()
-                        .map_err(warp_utils::reject::beacon_chain_error)?;
+                    let current_slot = chain.slot().map_err(warp_utils::reject::unhandled_error)?;
                     let current_epoch = current_slot.epoch(T::EthSpec::slots_per_epoch());
 
                     debug!(
@@ -3846,12 +3894,12 @@ pub fn serve<T: BeaconChainTypes>(
                             .execution_layer
                             .as_ref()
                             .ok_or(BeaconChainError::ExecutionLayerMissing)
-                            .map_err(warp_utils::reject::beacon_chain_error)?;
+                            .map_err(warp_utils::reject::unhandled_error)?;
                         let current_slot = chain
                             .slot_clock
                             .now_or_genesis()
                             .ok_or(BeaconChainError::UnableToReadSlot)
-                            .map_err(warp_utils::reject::beacon_chain_error)?;
+                            .map_err(warp_utils::reject::unhandled_error)?;
                         let current_epoch = current_slot.epoch(T::EthSpec::slots_per_epoch());
 
                         debug!(
@@ -3947,12 +3995,12 @@ pub fn serve<T: BeaconChainTypes>(
                                 .execution_layer
                                 .as_ref()
                                 .ok_or(BeaconChainError::ExecutionLayerMissing)
-                                .map_err(warp_utils::reject::beacon_chain_error)?
+                                .map_err(warp_utils::reject::unhandled_error)?
                                 .builder();
                             let builder = arc_builder
                                 .as_ref()
                                 .ok_or(BeaconChainError::BuilderMissing)
-                                .map_err(warp_utils::reject::beacon_chain_error)?;
+                                .map_err(warp_utils::reject::unhandled_error)?;
                             builder
                                 .post_builder_validators(&filtered_registration_data)
                                 .await
@@ -4068,9 +4116,8 @@ pub fn serve<T: BeaconChainTypes>(
              chain: Arc<BeaconChain<T>>| {
                 task_spawner.blocking_json_task(Priority::P0, move || {
                     // Ensure the request is for either the current, previous or next epoch.
-                    let current_epoch = chain
-                        .epoch()
-                        .map_err(warp_utils::reject::beacon_chain_error)?;
+                    let current_epoch =
+                        chain.epoch().map_err(warp_utils::reject::unhandled_error)?;
                     let prev_epoch = current_epoch.saturating_sub(Epoch::new(1));
                     let next_epoch = current_epoch.saturating_add(Epoch::new(1));
 
@@ -4109,9 +4156,8 @@ pub fn serve<T: BeaconChainTypes>(
              chain: Arc<BeaconChain<T>>| {
                 task_spawner.blocking_json_task(Priority::P0, move || {
                     // Ensure the request is for either the current, previous or next epoch.
-                    let current_epoch = chain
-                        .epoch()
-                        .map_err(warp_utils::reject::beacon_chain_error)?;
+                    let current_epoch =
+                        chain.epoch().map_err(warp_utils::reject::unhandled_error)?;
                     let prev_epoch = current_epoch.saturating_sub(Epoch::new(1));
                     let next_epoch = current_epoch.saturating_add(Epoch::new(1));
 
@@ -4613,6 +4659,9 @@ pub fn serve<T: BeaconChainTypes>(
                                 api_types::EventTopic::Attestation => {
                                     event_handler.subscribe_attestation()
                                 }
+                                api_types::EventTopic::SingleAttestation => {
+                                    event_handler.subscribe_single_attestation()
+                                }
                                 api_types::EventTopic::VoluntaryExit => {
                                     event_handler.subscribe_exit()
                                 }
@@ -4840,7 +4889,8 @@ pub fn serve<T: BeaconChainTypes>(
                     .uor(post_beacon_blinded_blocks)
                     .uor(post_beacon_blocks_v2)
                     .uor(post_beacon_blinded_blocks_v2)
-                    .uor(post_beacon_pool_attestations)
+                    .uor(post_beacon_pool_attestations_v1)
+                    .uor(post_beacon_pool_attestations_v2)
                     .uor(post_beacon_pool_attester_slashings)
                     .uor(post_beacon_pool_proposer_slashings)
                     .uor(post_beacon_pool_voluntary_exits)
@@ -4909,6 +4959,39 @@ pub fn serve<T: BeaconChainTypes>(
     Ok(http_server)
 }
 
+fn from_meta_data<E: EthSpec>(
+    meta_data: &RwLock<MetaData<E>>,
+    spec: &ChainSpec,
+) -> api_types::MetaData {
+    let meta_data = meta_data.read();
+    let format_hex = |bytes: &[u8]| format!("0x{}", hex::encode(bytes));
+
+    let seq_number = *meta_data.seq_number();
+    let attnets = format_hex(&meta_data.attnets().clone().into_bytes());
+    let syncnets = format_hex(
+        &meta_data
+            .syncnets()
+            .cloned()
+            .unwrap_or_default()
+            .into_bytes(),
+    );
+
+    if spec.is_peer_das_scheduled() {
+        api_types::MetaData::V3(api_types::MetaDataV3 {
+            seq_number,
+            attnets,
+            syncnets,
+            custody_group_count: meta_data.custody_group_count().cloned().unwrap_or_default(),
+        })
+    } else {
+        api_types::MetaData::V2(api_types::MetaDataV2 {
+            seq_number,
+            attnets,
+            syncnets,
+        })
+    }
+}
+
 /// Publish a message to the libp2p pubsub network.
 fn publish_pubsub_message<E: EthSpec>(
     network_tx: &UnboundedSender<NetworkMessage<E>>,
diff --git a/beacon_node/http_api/src/produce_block.rs b/beacon_node/http_api/src/produce_block.rs
index ed30da7362..0e24e8f175 100644
--- a/beacon_node/http_api/src/produce_block.rs
+++ b/beacon_node/http_api/src/produce_block.rs
@@ -153,7 +153,7 @@ pub async fn produce_blinded_block_v2<T: BeaconChainTypes>(
             BlockProductionVersion::BlindedV2,
         )
         .await
-        .map_err(warp_utils::reject::block_production_error)?;
+        .map_err(warp_utils::reject::unhandled_error)?;
 
     build_response_v2(chain, block_response_type, endpoint_version, accept_header)
 }
@@ -184,7 +184,7 @@ pub async fn produce_block_v2<T: BeaconChainTypes>(
             BlockProductionVersion::FullV2,
         )
         .await
-        .map_err(warp_utils::reject::block_production_error)?;
+        .map_err(warp_utils::reject::unhandled_error)?;
 
     build_response_v2(chain, block_response_type, endpoint_version, accept_header)
 }
diff --git a/beacon_node/http_api/src/proposer_duties.rs b/beacon_node/http_api/src/proposer_duties.rs
index 515599ce88..c4945df9d7 100644
--- a/beacon_node/http_api/src/proposer_duties.rs
+++ b/beacon_node/http_api/src/proposer_duties.rs
@@ -26,7 +26,7 @@ pub fn proposer_duties<T: BeaconChainTypes>(
         .now_or_genesis()
         .map(|slot| slot.epoch(T::EthSpec::slots_per_epoch()))
         .ok_or(BeaconChainError::UnableToReadSlot)
-        .map_err(warp_utils::reject::beacon_chain_error)?;
+        .map_err(warp_utils::reject::unhandled_error)?;
 
     // Determine what the current epoch would be if we fast-forward our system clock by
     // `MAXIMUM_GOSSIP_CLOCK_DISPARITY`.
@@ -66,7 +66,7 @@ pub fn proposer_duties<T: BeaconChainTypes>(
     {
         let (proposers, dependent_root, execution_status, _fork) =
             compute_proposer_duties_from_head(request_epoch, chain)
-                .map_err(warp_utils::reject::beacon_chain_error)?;
+                .map_err(warp_utils::reject::unhandled_error)?;
         convert_to_api_response(
             chain,
             request_epoch,
@@ -114,7 +114,7 @@ fn try_proposer_duties_from_cache<T: BeaconChainTypes>(
         .map_err(warp_utils::reject::beacon_state_error)?;
     let execution_optimistic = chain
         .is_optimistic_or_invalid_head_block(head_block)
-        .map_err(warp_utils::reject::beacon_chain_error)?;
+        .map_err(warp_utils::reject::unhandled_error)?;
 
     let dependent_root = match head_epoch.cmp(&request_epoch) {
         // head_epoch == request_epoch
@@ -163,7 +163,7 @@ fn compute_and_cache_proposer_duties<T: BeaconChainTypes>(
 ) -> Result<ApiDuties, warp::reject::Rejection> {
     let (indices, dependent_root, execution_status, fork) =
         compute_proposer_duties_from_head(current_epoch, chain)
-            .map_err(warp_utils::reject::beacon_chain_error)?;
+            .map_err(warp_utils::reject::unhandled_error)?;
 
     // Prime the proposer shuffling cache with the newly-learned value.
     chain
@@ -171,7 +171,7 @@ fn compute_and_cache_proposer_duties<T: BeaconChainTypes>(
         .lock()
         .insert(current_epoch, dependent_root, indices.clone(), fork)
         .map_err(BeaconChainError::from)
-        .map_err(warp_utils::reject::beacon_chain_error)?;
+        .map_err(warp_utils::reject::unhandled_error)?;
 
     convert_to_api_response(
         chain,
@@ -195,7 +195,7 @@ fn compute_historic_proposer_duties<T: BeaconChainTypes>(
         let (cached_head, execution_status) = chain
             .canonical_head
             .head_and_execution_status()
-            .map_err(warp_utils::reject::beacon_chain_error)?;
+            .map_err(warp_utils::reject::unhandled_error)?;
         let head = &cached_head.snapshot;
 
         if head.beacon_state.current_epoch() <= epoch {
@@ -214,7 +214,7 @@ fn compute_historic_proposer_duties<T: BeaconChainTypes>(
             // If we've loaded the head state it might be from a previous epoch, ensure it's in a
             // suitable epoch.
             ensure_state_is_in_epoch(&mut state, state_root, epoch, &chain.spec)
-                .map_err(warp_utils::reject::beacon_chain_error)?;
+                .map_err(warp_utils::reject::unhandled_error)?;
             (state, execution_optimistic)
         } else {
             let (state, execution_optimistic, _finalized) =
@@ -234,14 +234,14 @@ fn compute_historic_proposer_duties<T: BeaconChainTypes>(
     let indices = state
         .get_beacon_proposer_indices(&chain.spec)
         .map_err(BeaconChainError::from)
-        .map_err(warp_utils::reject::beacon_chain_error)?;
+        .map_err(warp_utils::reject::unhandled_error)?;
 
     // We can supply the genesis block root as the block root since we know that the only block that
     // decides its own root is the genesis block.
     let dependent_root = state
         .proposer_shuffling_decision_root(chain.genesis_block_root)
         .map_err(BeaconChainError::from)
-        .map_err(warp_utils::reject::beacon_chain_error)?;
+        .map_err(warp_utils::reject::unhandled_error)?;
 
     convert_to_api_response(chain, epoch, dependent_root, execution_optimistic, indices)
 }
@@ -257,7 +257,7 @@ fn convert_to_api_response<T: BeaconChainTypes>(
 ) -> Result<ApiDuties, warp::reject::Rejection> {
     let index_to_pubkey_map = chain
         .validator_pubkey_bytes_many(&indices)
-        .map_err(warp_utils::reject::beacon_chain_error)?;
+        .map_err(warp_utils::reject::unhandled_error)?;
 
     // Map our internal data structure into the API structure.
     let proposer_data = indices
diff --git a/beacon_node/http_api/src/publish_attestations.rs b/beacon_node/http_api/src/publish_attestations.rs
index 0065476532..1b9949d4d5 100644
--- a/beacon_node/http_api/src/publish_attestations.rs
+++ b/beacon_node/http_api/src/publish_attestations.rs
@@ -40,21 +40,24 @@ use beacon_chain::{
     BeaconChainTypes,
 };
 use beacon_processor::work_reprocessing_queue::{QueuedUnaggregate, ReprocessQueueMessage};
+use either::Either;
 use eth2::types::Failure;
 use lighthouse_network::PubsubMessage;
 use network::NetworkMessage;
+use serde_json::Value;
 use slog::{debug, error, warn, Logger};
+use std::borrow::Cow;
 use std::sync::Arc;
 use std::time::Duration;
 use tokio::sync::{
     mpsc::{Sender, UnboundedSender},
     oneshot,
 };
-use types::Attestation;
+use types::{Attestation, EthSpec, ForkName, SingleAttestation};
 
 // Error variants are only used in `Debug` and considered `dead_code` by the compiler.
 #[derive(Debug)]
-enum Error {
+pub enum Error {
     Validation(AttestationError),
     Publication,
     ForkChoice(#[allow(dead_code)] BeaconChainError),
@@ -62,6 +65,8 @@ enum Error {
     ReprocessDisabled,
     ReprocessFull,
     ReprocessTimeout,
+    InvalidJson(#[allow(dead_code)] serde_json::Error),
+    FailedConversion(#[allow(dead_code)] BeaconChainError),
 }
 
 enum PublishAttestationResult {
@@ -71,26 +76,71 @@ enum PublishAttestationResult {
     Failure(Error),
 }
 
+#[allow(clippy::type_complexity)]
+pub fn deserialize_attestation_payload<T: BeaconChainTypes>(
+    payload: Value,
+    fork_name: Option<ForkName>,
+    log: &Logger,
+) -> Result<Vec<Either<Attestation<T::EthSpec>, SingleAttestation>>, Error> {
+    if fork_name.is_some_and(|fork_name| fork_name.electra_enabled()) || fork_name.is_none() {
+        if fork_name.is_none() {
+            warn!(
+                log,
+                "No Consensus Version header specified.";
+            );
+        }
+
+        Ok(serde_json::from_value::<Vec<SingleAttestation>>(payload)
+            .map_err(Error::InvalidJson)?
+            .into_iter()
+            .map(Either::Right)
+            .collect())
+    } else {
+        Ok(
+            serde_json::from_value::<Vec<Attestation<T::EthSpec>>>(payload)
+                .map_err(Error::InvalidJson)?
+                .into_iter()
+                .map(Either::Left)
+                .collect(),
+        )
+    }
+}
+
 fn verify_and_publish_attestation<T: BeaconChainTypes>(
     chain: &Arc<BeaconChain<T>>,
-    attestation: &Attestation<T::EthSpec>,
+    either_attestation: &Either<Attestation<T::EthSpec>, SingleAttestation>,
     seen_timestamp: Duration,
     network_tx: &UnboundedSender<NetworkMessage<T::EthSpec>>,
     log: &Logger,
 ) -> Result<(), Error> {
-    let attestation = chain
-        .verify_unaggregated_attestation_for_gossip(attestation, None)
+    let attestation = convert_to_attestation(chain, either_attestation)?;
+    let verified_attestation = chain
+        .verify_unaggregated_attestation_for_gossip(&attestation, None)
         .map_err(Error::Validation)?;
 
-    // Publish.
-    network_tx
-        .send(NetworkMessage::Publish {
-            messages: vec![PubsubMessage::Attestation(Box::new((
-                attestation.subnet_id(),
-                attestation.attestation().clone_as_attestation(),
-            )))],
-        })
-        .map_err(|_| Error::Publication)?;
+    match either_attestation {
+        Either::Left(attestation) => {
+            // Publish.
+            network_tx
+                .send(NetworkMessage::Publish {
+                    messages: vec![PubsubMessage::Attestation(Box::new((
+                        verified_attestation.subnet_id(),
+                        attestation.clone(),
+                    )))],
+                })
+                .map_err(|_| Error::Publication)?;
+        }
+        Either::Right(single_attestation) => {
+            network_tx
+                .send(NetworkMessage::Publish {
+                    messages: vec![PubsubMessage::SingleAttestation(Box::new((
+                        verified_attestation.subnet_id(),
+                        single_attestation.clone(),
+                    )))],
+                })
+                .map_err(|_| Error::Publication)?;
+        }
+    }
 
     // Notify the validator monitor.
     chain
@@ -98,12 +148,12 @@ fn verify_and_publish_attestation<T: BeaconChainTypes>(
         .read()
         .register_api_unaggregated_attestation(
             seen_timestamp,
-            attestation.indexed_attestation(),
+            verified_attestation.indexed_attestation(),
             &chain.slot_clock,
         );
 
-    let fc_result = chain.apply_attestation_to_fork_choice(&attestation);
-    let naive_aggregation_result = chain.add_to_naive_aggregation_pool(&attestation);
+    let fc_result = chain.apply_attestation_to_fork_choice(&verified_attestation);
+    let naive_aggregation_result = chain.add_to_naive_aggregation_pool(&verified_attestation);
 
     if let Err(e) = &fc_result {
         warn!(
@@ -129,10 +179,48 @@ fn verify_and_publish_attestation<T: BeaconChainTypes>(
     }
 }
 
+fn convert_to_attestation<'a, T: BeaconChainTypes>(
+    chain: &Arc<BeaconChain<T>>,
+    attestation: &'a Either<Attestation<T::EthSpec>, SingleAttestation>,
+) -> Result<Cow<'a, Attestation<T::EthSpec>>, Error> {
+    let a = match attestation {
+        Either::Left(a) => Cow::Borrowed(a),
+        Either::Right(single_attestation) => chain
+            .with_committee_cache(
+                single_attestation.data.target.root,
+                single_attestation
+                    .data
+                    .slot
+                    .epoch(T::EthSpec::slots_per_epoch()),
+                |committee_cache, _| {
+                    let Some(committee) = committee_cache.get_beacon_committee(
+                        single_attestation.data.slot,
+                        single_attestation.committee_index,
+                    ) else {
+                        return Err(BeaconChainError::AttestationError(
+                            types::AttestationError::NoCommitteeForSlotAndIndex {
+                                slot: single_attestation.data.slot,
+                                index: single_attestation.committee_index,
+                            },
+                        ));
+                    };
+
+                    let attestation =
+                        single_attestation.to_attestation::<T::EthSpec>(committee.committee)?;
+
+                    Ok(Cow::Owned(attestation))
+                },
+            )
+            .map_err(Error::FailedConversion)?,
+    };
+
+    Ok(a)
+}
+
 pub async fn publish_attestations<T: BeaconChainTypes>(
     task_spawner: TaskSpawner<T::EthSpec>,
     chain: Arc<BeaconChain<T>>,
-    attestations: Vec<Attestation<T::EthSpec>>,
+    attestations: Vec<Either<Attestation<T::EthSpec>, SingleAttestation>>,
     network_tx: UnboundedSender<NetworkMessage<T::EthSpec>>,
     reprocess_send: Option<Sender<ReprocessQueueMessage>>,
     log: Logger,
@@ -141,7 +229,10 @@ pub async fn publish_attestations<T: BeaconChainTypes>(
     // move the `attestations` vec into the blocking task, so this small overhead is unavoidable.
     let attestation_metadata = attestations
         .iter()
-        .map(|att| (att.data().slot, att.committee_index()))
+        .map(|att| match att {
+            Either::Left(att) => (att.data().slot, att.committee_index()),
+            Either::Right(att) => (att.data.slot, Some(att.committee_index)),
+        })
         .collect::<Vec<_>>();
 
     // Gossip validate and publish attestations that can be immediately processed.
diff --git a/beacon_node/http_api/src/publish_blocks.rs b/beacon_node/http_api/src/publish_blocks.rs
index b5aa23acf8..60d4b2f16e 100644
--- a/beacon_node/http_api/src/publish_blocks.rs
+++ b/beacon_node/http_api/src/publish_blocks.rs
@@ -395,9 +395,8 @@ fn build_gossip_verified_data_columns<T: BeaconChainTypes>(
     let gossip_verified_data_columns = data_column_sidecars
         .into_iter()
         .map(|data_column_sidecar| {
-            let column_index = data_column_sidecar.index as usize;
-            let subnet =
-                DataColumnSubnetId::from_column_index::<T::EthSpec>(column_index, &chain.spec);
+            let column_index = data_column_sidecar.index;
+            let subnet = DataColumnSubnetId::from_column_index(column_index, &chain.spec);
             let gossip_verified_column =
                 GossipVerifiedDataColumn::new(data_column_sidecar, subnet.into(), chain);
 
@@ -520,10 +519,7 @@ fn publish_column_sidecars<T: BeaconChainTypes>(
     let pubsub_messages = data_column_sidecars
         .into_iter()
         .map(|data_col| {
-            let subnet = DataColumnSubnetId::from_column_index::<T::EthSpec>(
-                data_col.index as usize,
-                &chain.spec,
-            );
+            let subnet = DataColumnSubnetId::from_column_index(data_col.index, &chain.spec);
             PubsubMessage::DataColumnSidecar(Box::new((subnet, data_col)))
         })
         .collect::<Vec<_>>();
diff --git a/beacon_node/http_api/src/standard_block_rewards.rs b/beacon_node/http_api/src/standard_block_rewards.rs
index 1ab75374ea..372a2765da 100644
--- a/beacon_node/http_api/src/standard_block_rewards.rs
+++ b/beacon_node/http_api/src/standard_block_rewards.rs
@@ -4,7 +4,7 @@ use crate::ExecutionOptimistic;
 use beacon_chain::{BeaconChain, BeaconChainTypes};
 use eth2::lighthouse::StandardBlockReward;
 use std::sync::Arc;
-use warp_utils::reject::beacon_chain_error;
+use warp_utils::reject::unhandled_error;
 /// The difference between block_rewards and beacon_block_rewards is the later returns block
 /// reward format that satisfies beacon-api specs
 pub fn compute_beacon_block_rewards<T: BeaconChainTypes>(
@@ -19,7 +19,7 @@ pub fn compute_beacon_block_rewards<T: BeaconChainTypes>(
 
     let rewards = chain
         .compute_beacon_block_reward(block_ref, &mut state)
-        .map_err(beacon_chain_error)?;
+        .map_err(unhandled_error)?;
 
     Ok((rewards, execution_optimistic, finalized))
 }
diff --git a/beacon_node/http_api/src/state_id.rs b/beacon_node/http_api/src/state_id.rs
index ddacde9a3f..353390cdad 100644
--- a/beacon_node/http_api/src/state_id.rs
+++ b/beacon_node/http_api/src/state_id.rs
@@ -30,7 +30,7 @@ impl StateId {
                 let (cached_head, execution_status) = chain
                     .canonical_head
                     .head_and_execution_status()
-                    .map_err(warp_utils::reject::beacon_chain_error)?;
+                    .map_err(warp_utils::reject::unhandled_error)?;
                 return Ok((
                     cached_head.head_state_root(),
                     execution_status.is_optimistic_or_invalid(),
@@ -56,7 +56,7 @@ impl StateId {
                 *slot,
                 chain
                     .is_optimistic_or_invalid_head()
-                    .map_err(warp_utils::reject::beacon_chain_error)?,
+                    .map_err(warp_utils::reject::unhandled_error)?,
                 *slot
                     <= chain
                         .canonical_head
@@ -70,11 +70,11 @@ impl StateId {
                     .store
                     .load_hot_state_summary(root)
                     .map_err(BeaconChainError::DBError)
-                    .map_err(warp_utils::reject::beacon_chain_error)?
+                    .map_err(warp_utils::reject::unhandled_error)?
                 {
                     let finalization_status = chain
                         .state_finalization_and_canonicity(root, hot_summary.slot)
-                        .map_err(warp_utils::reject::beacon_chain_error)?;
+                        .map_err(warp_utils::reject::unhandled_error)?;
                     let finalized = finalization_status.is_finalized();
                     let fork_choice = chain.canonical_head.fork_choice_read_lock();
                     let execution_optimistic = if finalization_status.slot_is_finalized
@@ -94,14 +94,14 @@ impl StateId {
                         fork_choice
                             .is_optimistic_or_invalid_block(&hot_summary.latest_block_root)
                             .map_err(BeaconChainError::ForkChoiceError)
-                            .map_err(warp_utils::reject::beacon_chain_error)?
+                            .map_err(warp_utils::reject::unhandled_error)?
                     };
                     return Ok((*root, execution_optimistic, finalized));
                 } else if let Some(_cold_state_slot) = chain
                     .store
                     .load_cold_state_slot(root)
                     .map_err(BeaconChainError::DBError)
-                    .map_err(warp_utils::reject::beacon_chain_error)?
+                    .map_err(warp_utils::reject::unhandled_error)?
                 {
                     let fork_choice = chain.canonical_head.fork_choice_read_lock();
                     let finalized_root = fork_choice
@@ -111,7 +111,7 @@ impl StateId {
                     let execution_optimistic = fork_choice
                         .is_optimistic_or_invalid_block_no_fallback(&finalized_root)
                         .map_err(BeaconChainError::ForkChoiceError)
-                        .map_err(warp_utils::reject::beacon_chain_error)?;
+                        .map_err(warp_utils::reject::unhandled_error)?;
                     return Ok((*root, execution_optimistic, true));
                 } else {
                     return Err(warp_utils::reject::custom_not_found(format!(
@@ -124,7 +124,7 @@ impl StateId {
 
         let root = chain
             .state_root_at_slot(slot)
-            .map_err(warp_utils::reject::beacon_chain_error)?
+            .map_err(warp_utils::reject::unhandled_error)?
             .ok_or_else(|| {
                 warp_utils::reject::custom_not_found(format!("beacon state at slot {}", slot))
             })?;
@@ -178,7 +178,7 @@ impl StateId {
                 let (cached_head, execution_status) = chain
                     .canonical_head
                     .head_and_execution_status()
-                    .map_err(warp_utils::reject::beacon_chain_error)?;
+                    .map_err(warp_utils::reject::unhandled_error)?;
                 return Ok((
                     cached_head.snapshot.beacon_state.clone(),
                     execution_status.is_optimistic_or_invalid(),
@@ -191,7 +191,7 @@ impl StateId {
 
         let state = chain
             .get_state(&state_root, slot_opt)
-            .map_err(warp_utils::reject::beacon_chain_error)
+            .map_err(warp_utils::reject::unhandled_error)
             .and_then(|opt| {
                 opt.ok_or_else(|| {
                     warp_utils::reject::custom_not_found(format!(
@@ -224,7 +224,7 @@ impl StateId {
                 let (head, execution_status) = chain
                     .canonical_head
                     .head_and_execution_status()
-                    .map_err(warp_utils::reject::beacon_chain_error)?;
+                    .map_err(warp_utils::reject::unhandled_error)?;
                 return func(
                     &head.snapshot.beacon_state,
                     execution_status.is_optimistic_or_invalid(),
@@ -273,7 +273,7 @@ pub fn checkpoint_slot_and_execution_optimistic<T: BeaconChainTypes>(
     let execution_optimistic = fork_choice
         .is_optimistic_or_invalid_block_no_fallback(root)
         .map_err(BeaconChainError::ForkChoiceError)
-        .map_err(warp_utils::reject::beacon_chain_error)?;
+        .map_err(warp_utils::reject::unhandled_error)?;
 
     Ok((slot, execution_optimistic))
 }
diff --git a/beacon_node/http_api/src/sync_committee_rewards.rs b/beacon_node/http_api/src/sync_committee_rewards.rs
index 68a06b1ce8..ec63372406 100644
--- a/beacon_node/http_api/src/sync_committee_rewards.rs
+++ b/beacon_node/http_api/src/sync_committee_rewards.rs
@@ -6,7 +6,7 @@ use slog::{debug, Logger};
 use state_processing::BlockReplayer;
 use std::sync::Arc;
 use types::{BeaconState, SignedBlindedBeaconBlock};
-use warp_utils::reject::{beacon_chain_error, custom_not_found};
+use warp_utils::reject::{custom_not_found, unhandled_error};
 
 pub fn compute_sync_committee_rewards<T: BeaconChainTypes>(
     chain: Arc<BeaconChain<T>>,
@@ -20,7 +20,7 @@ pub fn compute_sync_committee_rewards<T: BeaconChainTypes>(
 
     let reward_payload = chain
         .compute_sync_committee_rewards(block.message(), &mut state)
-        .map_err(beacon_chain_error)?;
+        .map_err(unhandled_error)?;
 
     let data = if reward_payload.is_empty() {
         debug!(log, "compute_sync_committee_rewards returned empty");
@@ -71,7 +71,7 @@ pub fn get_state_before_applying_block<T: BeaconChainTypes>(
         .state_root_iter([Ok((parent_block.state_root(), parent_block.slot()))].into_iter())
         .minimal_block_root_verification()
         .apply_blocks(vec![], Some(block.slot()))
-        .map_err(beacon_chain_error)?;
+        .map_err(unhandled_error::<BeaconChainError>)?;
 
     Ok(replayer.into_state())
 }
diff --git a/beacon_node/http_api/src/sync_committees.rs b/beacon_node/http_api/src/sync_committees.rs
index 3e5b1dc524..da9f9b7a06 100644
--- a/beacon_node/http_api/src/sync_committees.rs
+++ b/beacon_node/http_api/src/sync_committees.rs
@@ -39,7 +39,7 @@ pub fn sync_committee_duties<T: BeaconChainTypes>(
     // still dependent on the head. So using `is_optimistic_head` is fine for both cases.
     let execution_optimistic = chain
         .is_optimistic_or_invalid_head()
-        .map_err(warp_utils::reject::beacon_chain_error)?;
+        .map_err(warp_utils::reject::unhandled_error)?;
 
     // Try using the head's sync committees to satisfy the request. This should be sufficient for
     // the vast majority of requests. Rather than checking if we think the request will succeed in a
@@ -55,7 +55,7 @@ pub fn sync_committee_duties<T: BeaconChainTypes>(
             ..
         }))
         | Err(BeaconChainError::SyncDutiesError(BeaconStateError::IncorrectStateVariant)) => (),
-        Err(e) => return Err(warp_utils::reject::beacon_chain_error(e)),
+        Err(e) => return Err(warp_utils::reject::unhandled_error(e)),
     }
 
     let duties = duties_from_state_load(request_epoch, request_indices, altair_fork_epoch, chain)
@@ -67,7 +67,7 @@ pub fn sync_committee_duties<T: BeaconChainTypes>(
             "invalid epoch: {}, current epoch: {}",
             request_epoch, current_epoch
         )),
-        e => warp_utils::reject::beacon_chain_error(e),
+        e => warp_utils::reject::unhandled_error(e),
     })?;
     Ok(convert_to_response(
         verify_unknown_validators(duties, request_epoch, chain)?,
@@ -164,7 +164,7 @@ fn verify_unknown_validators<T: BeaconChainTypes>(
             BeaconChainError::SyncDutiesError(BeaconStateError::UnknownValidator(idx)) => {
                 warp_utils::reject::custom_bad_request(format!("invalid validator index: {idx}"))
             }
-            e => warp_utils::reject::beacon_chain_error(e),
+            e => warp_utils::reject::unhandled_error(e),
         })
 }
 
diff --git a/beacon_node/http_api/src/test_utils.rs b/beacon_node/http_api/src/test_utils.rs
index 7b48d64e36..fbc92a45cc 100644
--- a/beacon_node/http_api/src/test_utils.rs
+++ b/beacon_node/http_api/src/test_utils.rs
@@ -8,6 +8,7 @@ use beacon_processor::{
 };
 use directory::DEFAULT_ROOT_DIR;
 use eth2::{BeaconNodeHttpClient, Timeouts};
+use lighthouse_network::rpc::methods::MetaDataV3;
 use lighthouse_network::{
     discv5::enr::CombinedKey,
     libp2p::swarm::{
@@ -150,11 +151,21 @@ pub async fn create_api_server_with_config<T: BeaconChainTypes>(
     let (network_senders, network_receivers) = NetworkSenders::new();
 
     // Default metadata
-    let meta_data = MetaData::V2(MetaDataV2 {
-        seq_number: SEQ_NUMBER,
-        attnets: EnrAttestationBitfield::<T::EthSpec>::default(),
-        syncnets: EnrSyncCommitteeBitfield::<T::EthSpec>::default(),
-    });
+    let meta_data = if chain.spec.is_peer_das_scheduled() {
+        MetaData::V3(MetaDataV3 {
+            seq_number: SEQ_NUMBER,
+            attnets: EnrAttestationBitfield::<T::EthSpec>::default(),
+            syncnets: EnrSyncCommitteeBitfield::<T::EthSpec>::default(),
+            custody_group_count: chain.spec.custody_requirement,
+        })
+    } else {
+        MetaData::V2(MetaDataV2 {
+            seq_number: SEQ_NUMBER,
+            attnets: EnrAttestationBitfield::<T::EthSpec>::default(),
+            syncnets: EnrSyncCommitteeBitfield::<T::EthSpec>::default(),
+        })
+    };
+
     let enr_key = CombinedKey::generate_secp256k1();
     let enr = Enr::builder().build(&enr_key).unwrap();
     let network_config = Arc::new(NetworkConfig::default());
diff --git a/beacon_node/http_api/src/ui.rs b/beacon_node/http_api/src/ui.rs
index 616745dbef..80a9ed896d 100644
--- a/beacon_node/http_api/src/ui.rs
+++ b/beacon_node/http_api/src/ui.rs
@@ -5,7 +5,7 @@ use eth2::types::{Epoch, ValidatorStatus};
 use serde::{Deserialize, Serialize};
 use std::collections::{HashMap, HashSet};
 use std::sync::Arc;
-use warp_utils::reject::beacon_chain_error;
+use warp_utils::reject::unhandled_error;
 
 #[derive(Debug, Default, Clone, PartialEq, Serialize, Deserialize)]
 pub struct ValidatorCountResponse {
@@ -58,7 +58,7 @@ pub fn get_validator_count<T: BeaconChainTypes>(
             }
             Ok::<(), BeaconChainError>(())
         })
-        .map_err(beacon_chain_error)?;
+        .map_err(unhandled_error)?;
 
     Ok(ValidatorCountResponse {
         active_ongoing,
@@ -101,7 +101,7 @@ pub fn get_validator_info<T: BeaconChainTypes>(
     request_data: ValidatorInfoRequestData,
     chain: Arc<BeaconChain<T>>,
 ) -> Result<ValidatorInfoResponse, warp::Rejection> {
-    let current_epoch = chain.epoch().map_err(beacon_chain_error)?;
+    let current_epoch = chain.epoch().map_err(unhandled_error)?;
 
     let epochs = current_epoch.saturating_sub(HISTORIC_EPOCHS).as_u64()..=current_epoch.as_u64();
 
diff --git a/beacon_node/http_api/src/validator.rs b/beacon_node/http_api/src/validator.rs
index 7f11ddd8f4..baa41e33ed 100644
--- a/beacon_node/http_api/src/validator.rs
+++ b/beacon_node/http_api/src/validator.rs
@@ -14,7 +14,7 @@ pub fn pubkey_to_validator_index<T: BeaconChainTypes>(
             state
                 .validators()
                 .get(index)
-                .map_or(false, |v| v.pubkey == *pubkey)
+                .is_some_and(|v| v.pubkey == *pubkey)
         })
         .map(Result::Ok)
         .transpose()
diff --git a/beacon_node/http_api/tests/broadcast_validation_tests.rs b/beacon_node/http_api/tests/broadcast_validation_tests.rs
index e1ecf2d4fc..1baa71699c 100644
--- a/beacon_node/http_api/tests/broadcast_validation_tests.rs
+++ b/beacon_node/http_api/tests/broadcast_validation_tests.rs
@@ -1,4 +1,3 @@
-use beacon_chain::blob_verification::GossipVerifiedBlob;
 use beacon_chain::{
     test_utils::{AttestationStrategy, BlockStrategy},
     GossipVerifiedBlock, IntoGossipVerifiedBlock,
@@ -7,9 +6,10 @@ use eth2::reqwest::StatusCode;
 use eth2::types::{BroadcastValidation, PublishBlockRequest};
 use http_api::test_utils::InteractiveTester;
 use http_api::{publish_blinded_block, publish_block, reconstruct_block, Config, ProvenancedBlock};
+use std::collections::HashSet;
 use std::sync::Arc;
 use types::{
-    BlobSidecar, Epoch, EthSpec, FixedBytesExtended, ForkName, Hash256, MainnetEthSpec, Slot,
+    ColumnIndex, Epoch, EthSpec, FixedBytesExtended, ForkName, Hash256, MainnetEthSpec, Slot,
 };
 use warp::Rejection;
 use warp_utils::reject::CustomBadRequest;
@@ -17,6 +17,8 @@ use warp_utils::reject::CustomBadRequest;
 type E = MainnetEthSpec;
 
 /*
+ * TODO(fulu): write PeerDAS equivalent tests for these.
+ *
  * We have the following test cases, which are duplicated for the blinded variant of the route:
  *
  * -  `broadcast_validation=gossip`
@@ -75,7 +77,7 @@ pub async fn gossip_invalid() {
 
     let response: Result<(), eth2::Error> = tester
         .client
-        .post_beacon_blocks_v2(&PublishBlockRequest::new(block, blobs), validation_level)
+        .post_beacon_blocks_v2_ssz(&PublishBlockRequest::new(block, blobs), validation_level)
         .await;
     assert!(response.is_err());
 
@@ -124,7 +126,7 @@ pub async fn gossip_partial_pass() {
 
     let response: Result<(), eth2::Error> = tester
         .client
-        .post_beacon_blocks_v2(&PublishBlockRequest::new(block, blobs), validation_level)
+        .post_beacon_blocks_v2_ssz(&PublishBlockRequest::new(block, blobs), validation_level)
         .await;
     assert!(response.is_err());
 
@@ -165,7 +167,7 @@ pub async fn gossip_full_pass() {
 
     let response: Result<(), eth2::Error> = tester
         .client
-        .post_beacon_blocks_v2(
+        .post_beacon_blocks_v2_ssz(
             &PublishBlockRequest::new(block.clone(), blobs),
             validation_level,
         )
@@ -261,7 +263,7 @@ pub async fn consensus_invalid() {
 
     let response: Result<(), eth2::Error> = tester
         .client
-        .post_beacon_blocks_v2(&PublishBlockRequest::new(block, blobs), validation_level)
+        .post_beacon_blocks_v2_ssz(&PublishBlockRequest::new(block, blobs), validation_level)
         .await;
     assert!(response.is_err());
 
@@ -307,7 +309,7 @@ pub async fn consensus_gossip() {
 
     let response: Result<(), eth2::Error> = tester
         .client
-        .post_beacon_blocks_v2(&PublishBlockRequest::new(block, blobs), validation_level)
+        .post_beacon_blocks_v2_ssz(&PublishBlockRequest::new(block, blobs), validation_level)
         .await;
     assert!(response.is_err());
 
@@ -423,7 +425,7 @@ pub async fn consensus_full_pass() {
 
     let response: Result<(), eth2::Error> = tester
         .client
-        .post_beacon_blocks_v2(
+        .post_beacon_blocks_v2_ssz(
             &PublishBlockRequest::new(block.clone(), blobs),
             validation_level,
         )
@@ -475,7 +477,7 @@ pub async fn equivocation_invalid() {
 
     let response: Result<(), eth2::Error> = tester
         .client
-        .post_beacon_blocks_v2(&PublishBlockRequest::new(block, blobs), validation_level)
+        .post_beacon_blocks_v2_ssz(&PublishBlockRequest::new(block, blobs), validation_level)
         .await;
     assert!(response.is_err());
 
@@ -533,7 +535,7 @@ pub async fn equivocation_consensus_early_equivocation() {
     /* submit `block_a` as valid */
     assert!(tester
         .client
-        .post_beacon_blocks_v2(
+        .post_beacon_blocks_v2_ssz(
             &PublishBlockRequest::new(block_a.clone(), blobs_a),
             validation_level
         )
@@ -547,7 +549,7 @@ pub async fn equivocation_consensus_early_equivocation() {
     /* submit `block_b` which should induce equivocation */
     let response: Result<(), eth2::Error> = tester
         .client
-        .post_beacon_blocks_v2(
+        .post_beacon_blocks_v2_ssz(
             &PublishBlockRequest::new(block_b.clone(), blobs_b),
             validation_level,
         )
@@ -596,7 +598,7 @@ pub async fn equivocation_gossip() {
 
     let response: Result<(), eth2::Error> = tester
         .client
-        .post_beacon_blocks_v2(&PublishBlockRequest::new(block, blobs), validation_level)
+        .post_beacon_blocks_v2_ssz(&PublishBlockRequest::new(block, blobs), validation_level)
         .await;
     assert!(response.is_err());
 
@@ -721,7 +723,7 @@ pub async fn equivocation_full_pass() {
 
     let response: Result<(), eth2::Error> = tester
         .client
-        .post_beacon_blocks_v2(
+        .post_beacon_blocks_v2_ssz(
             &PublishBlockRequest::new(block.clone(), blobs),
             validation_level,
         )
@@ -1375,7 +1377,7 @@ pub async fn block_seen_on_gossip_without_blobs() {
     // `validator_count // 32`.
     let validator_count = 64;
     let num_initial: u64 = 31;
-    let spec = ForkName::latest().make_genesis_spec(E::default_spec());
+    let spec = ForkName::latest_stable().make_genesis_spec(E::default_spec());
     let tester = InteractiveTester::<E>::new(Some(spec), validator_count).await;
 
     // Create some chain depth.
@@ -1413,7 +1415,7 @@ pub async fn block_seen_on_gossip_without_blobs() {
     // Post the block *and* blobs to the HTTP API.
     let response: Result<(), eth2::Error> = tester
         .client
-        .post_beacon_blocks_v2(
+        .post_beacon_blocks_v2_ssz(
             &PublishBlockRequest::new(block.clone(), Some(blobs)),
             validation_level,
         )
@@ -1437,7 +1439,7 @@ pub async fn block_seen_on_gossip_with_some_blobs() {
     // `validator_count // 32`.
     let validator_count = 64;
     let num_initial: u64 = 31;
-    let spec = ForkName::latest().make_genesis_spec(E::default_spec());
+    let spec = ForkName::latest_stable().make_genesis_spec(E::default_spec());
     let tester = InteractiveTester::<E>::new(Some(spec), validator_count).await;
 
     // Create some chain depth.
@@ -1460,11 +1462,12 @@ pub async fn block_seen_on_gossip_with_some_blobs() {
     let blobs = blobs.expect("should have some blobs");
     assert!(
         blobs.0.len() >= 2,
-        "need at least 2 blobs for partial reveal"
+        "need at least 2 blobs for partial reveal, got: {}",
+        blobs.0.len()
     );
 
-    let partial_kzg_proofs = vec![*blobs.0.first().unwrap()];
-    let partial_blobs = vec![blobs.1.first().unwrap().clone()];
+    let partial_kzg_proofs = [*blobs.0.first().unwrap()];
+    let partial_blobs = [blobs.1.first().unwrap().clone()];
 
     // Simulate the block being seen on gossip.
     block
@@ -1473,21 +1476,15 @@ pub async fn block_seen_on_gossip_with_some_blobs() {
         .unwrap();
 
     // Simulate some of the blobs being seen on gossip.
-    for (i, (kzg_proof, blob)) in partial_kzg_proofs
-        .into_iter()
-        .zip(partial_blobs)
-        .enumerate()
-    {
-        let sidecar = Arc::new(BlobSidecar::new(i, blob, &block, kzg_proof).unwrap());
-        let gossip_blob =
-            GossipVerifiedBlob::new(sidecar, i as u64, &tester.harness.chain).unwrap();
-        tester
-            .harness
-            .chain
-            .process_gossip_blob(gossip_blob)
-            .await
-            .unwrap();
-    }
+    tester
+        .harness
+        .process_gossip_blobs_or_columns(
+            &block,
+            partial_blobs.iter(),
+            partial_kzg_proofs.iter(),
+            Some(get_custody_columns(&tester)),
+        )
+        .await;
 
     // It should not yet be added to fork choice because all blobs have not been seen.
     assert!(!tester
@@ -1498,7 +1495,7 @@ pub async fn block_seen_on_gossip_with_some_blobs() {
     // Post the block *and* all blobs to the HTTP API.
     let response: Result<(), eth2::Error> = tester
         .client
-        .post_beacon_blocks_v2(
+        .post_beacon_blocks_v2_ssz(
             &PublishBlockRequest::new(block.clone(), Some(blobs)),
             validation_level,
         )
@@ -1522,7 +1519,7 @@ pub async fn blobs_seen_on_gossip_without_block() {
     // `validator_count // 32`.
     let validator_count = 64;
     let num_initial: u64 = 31;
-    let spec = ForkName::latest().make_genesis_spec(E::default_spec());
+    let spec = ForkName::latest_stable().make_genesis_spec(E::default_spec());
     let tester = InteractiveTester::<E>::new(Some(spec), validator_count).await;
 
     // Create some chain depth.
@@ -1545,22 +1542,15 @@ pub async fn blobs_seen_on_gossip_without_block() {
     let (kzg_proofs, blobs) = blobs.expect("should have some blobs");
 
     // Simulate the blobs being seen on gossip.
-    for (i, (kzg_proof, blob)) in kzg_proofs
-        .clone()
-        .into_iter()
-        .zip(blobs.clone())
-        .enumerate()
-    {
-        let sidecar = Arc::new(BlobSidecar::new(i, blob, &block, kzg_proof).unwrap());
-        let gossip_blob =
-            GossipVerifiedBlob::new(sidecar, i as u64, &tester.harness.chain).unwrap();
-        tester
-            .harness
-            .chain
-            .process_gossip_blob(gossip_blob)
-            .await
-            .unwrap();
-    }
+    tester
+        .harness
+        .process_gossip_blobs_or_columns(
+            &block,
+            blobs.iter(),
+            kzg_proofs.iter(),
+            Some(get_custody_columns(&tester)),
+        )
+        .await;
 
     // It should not yet be added to fork choice because the block has not been seen.
     assert!(!tester
@@ -1571,7 +1561,7 @@ pub async fn blobs_seen_on_gossip_without_block() {
     // Post the block *and* all blobs to the HTTP API.
     let response: Result<(), eth2::Error> = tester
         .client
-        .post_beacon_blocks_v2(
+        .post_beacon_blocks_v2_ssz(
             &PublishBlockRequest::new(block.clone(), Some((kzg_proofs, blobs))),
             validation_level,
         )
@@ -1595,7 +1585,7 @@ pub async fn blobs_seen_on_gossip_without_block_and_no_http_blobs() {
     // `validator_count // 32`.
     let validator_count = 64;
     let num_initial: u64 = 31;
-    let spec = ForkName::latest().make_genesis_spec(E::default_spec());
+    let spec = ForkName::latest_stable().make_genesis_spec(E::default_spec());
     let tester = InteractiveTester::<E>::new(Some(spec), validator_count).await;
 
     // Create some chain depth.
@@ -1619,22 +1609,15 @@ pub async fn blobs_seen_on_gossip_without_block_and_no_http_blobs() {
     assert!(!blobs.is_empty());
 
     // Simulate the blobs being seen on gossip.
-    for (i, (kzg_proof, blob)) in kzg_proofs
-        .clone()
-        .into_iter()
-        .zip(blobs.clone())
-        .enumerate()
-    {
-        let sidecar = Arc::new(BlobSidecar::new(i, blob, &block, kzg_proof).unwrap());
-        let gossip_blob =
-            GossipVerifiedBlob::new(sidecar, i as u64, &tester.harness.chain).unwrap();
-        tester
-            .harness
-            .chain
-            .process_gossip_blob(gossip_blob)
-            .await
-            .unwrap();
-    }
+    tester
+        .harness
+        .process_gossip_blobs_or_columns(
+            &block,
+            blobs.iter(),
+            kzg_proofs.iter(),
+            Some(get_custody_columns(&tester)),
+        )
+        .await;
 
     // It should not yet be added to fork choice because the block has not been seen.
     assert!(!tester
@@ -1645,7 +1628,7 @@ pub async fn blobs_seen_on_gossip_without_block_and_no_http_blobs() {
     // Post just the block to the HTTP API (blob lists are empty).
     let response: Result<(), eth2::Error> = tester
         .client
-        .post_beacon_blocks_v2(
+        .post_beacon_blocks_v2_ssz(
             &PublishBlockRequest::new(
                 block.clone(),
                 Some((Default::default(), Default::default())),
@@ -1671,7 +1654,7 @@ pub async fn slashable_blobs_seen_on_gossip_cause_failure() {
     // `validator_count // 32`.
     let validator_count = 64;
     let num_initial: u64 = 31;
-    let spec = ForkName::latest().make_genesis_spec(E::default_spec());
+    let spec = ForkName::latest_stable().make_genesis_spec(E::default_spec());
     let tester = InteractiveTester::<E>::new(Some(spec), validator_count).await;
 
     // Create some chain depth.
@@ -1696,17 +1679,15 @@ pub async fn slashable_blobs_seen_on_gossip_cause_failure() {
     let (kzg_proofs_b, blobs_b) = blobs_b.expect("should have some blobs");
 
     // Simulate the blobs of block B being seen on gossip.
-    for (i, (kzg_proof, blob)) in kzg_proofs_b.into_iter().zip(blobs_b).enumerate() {
-        let sidecar = Arc::new(BlobSidecar::new(i, blob, &block_b, kzg_proof).unwrap());
-        let gossip_blob =
-            GossipVerifiedBlob::new(sidecar, i as u64, &tester.harness.chain).unwrap();
-        tester
-            .harness
-            .chain
-            .process_gossip_blob(gossip_blob)
-            .await
-            .unwrap();
-    }
+    tester
+        .harness
+        .process_gossip_blobs_or_columns(
+            &block_b,
+            blobs_b.iter(),
+            kzg_proofs_b.iter(),
+            Some(get_custody_columns(&tester)),
+        )
+        .await;
 
     // It should not yet be added to fork choice because block B has not been seen.
     assert!(!tester
@@ -1717,7 +1698,7 @@ pub async fn slashable_blobs_seen_on_gossip_cause_failure() {
     // Post block A *and* all its blobs to the HTTP API.
     let response: Result<(), eth2::Error> = tester
         .client
-        .post_beacon_blocks_v2(
+        .post_beacon_blocks_v2_ssz(
             &PublishBlockRequest::new(block_a.clone(), Some((kzg_proofs_a, blobs_a))),
             validation_level,
         )
@@ -1741,7 +1722,7 @@ pub async fn duplicate_block_status_code() {
     // `validator_count // 32`.
     let validator_count = 64;
     let num_initial: u64 = 31;
-    let spec = ForkName::latest().make_genesis_spec(E::default_spec());
+    let spec = ForkName::latest_stable().make_genesis_spec(E::default_spec());
     let duplicate_block_status_code = StatusCode::IM_A_TEAPOT;
     let tester = InteractiveTester::<E>::new_with_initializer_and_mutator(
         Some(spec),
@@ -1778,7 +1759,7 @@ pub async fn duplicate_block_status_code() {
     let block_request = PublishBlockRequest::new(block.clone(), Some((kzg_proofs, blobs)));
     let response: Result<(), eth2::Error> = tester
         .client
-        .post_beacon_blocks_v2(&block_request, validation_level)
+        .post_beacon_blocks_v2_ssz(&block_request, validation_level)
         .await;
 
     // This should result in the block being fully imported.
@@ -1791,7 +1772,7 @@ pub async fn duplicate_block_status_code() {
     // Post again.
     let duplicate_response: Result<(), eth2::Error> = tester
         .client
-        .post_beacon_blocks_v2(&block_request, validation_level)
+        .post_beacon_blocks_v2_ssz(&block_request, validation_level)
         .await;
     let err = duplicate_response.unwrap_err();
     assert_eq!(err.status().unwrap(), duplicate_block_status_code);
@@ -1803,3 +1784,13 @@ fn assert_server_message_error(error_response: eth2::Error, expected_message: St
     };
     assert_eq!(err.message, expected_message);
 }
+
+fn get_custody_columns(tester: &InteractiveTester<E>) -> HashSet<ColumnIndex> {
+    tester
+        .ctx
+        .network_globals
+        .as_ref()
+        .unwrap()
+        .sampling_columns
+        .clone()
+}
diff --git a/beacon_node/http_api/tests/fork_tests.rs b/beacon_node/http_api/tests/fork_tests.rs
index 8cb6053e9f..d6b8df33b3 100644
--- a/beacon_node/http_api/tests/fork_tests.rs
+++ b/beacon_node/http_api/tests/fork_tests.rs
@@ -155,10 +155,6 @@ async fn attestations_across_fork_with_skip_slots() {
         .post_beacon_pool_attestations_v1(&unaggregated_attestations)
         .await
         .unwrap();
-    client
-        .post_beacon_pool_attestations_v2(&unaggregated_attestations, fork_name)
-        .await
-        .unwrap();
 
     let signed_aggregates = attestations
         .into_iter()
diff --git a/beacon_node/http_api/tests/interactive_tests.rs b/beacon_node/http_api/tests/interactive_tests.rs
index e45dcf221c..bb3086945b 100644
--- a/beacon_node/http_api/tests/interactive_tests.rs
+++ b/beacon_node/http_api/tests/interactive_tests.rs
@@ -5,6 +5,7 @@ use beacon_chain::{
     ChainConfig,
 };
 use beacon_processor::work_reprocessing_queue::ReprocessQueueMessage;
+use either::Either;
 use eth2::types::ProduceBlockV3Response;
 use eth2::types::{DepositContractData, StateId};
 use execution_layer::{ForkchoiceState, PayloadAttributes};
@@ -161,7 +162,7 @@ impl ForkChoiceUpdates {
                 update
                     .payload_attributes
                     .as_ref()
-                    .map_or(false, |payload_attributes| {
+                    .is_some_and(|payload_attributes| {
                         payload_attributes.timestamp() == proposal_timestamp
                     })
             })
@@ -890,27 +891,50 @@ async fn queue_attestations_from_http() {
     let pre_state = harness.get_current_state();
     let (block, post_state) = harness.make_block(pre_state, attestation_slot).await;
     let block_root = block.0.canonical_root();
+    let fork_name = tester.harness.spec.fork_name_at_slot::<E>(attestation_slot);
 
     // Make attestations to the block and POST them to the beacon node on a background thread.
-    let attestations = harness
-        .make_unaggregated_attestations(
-            &all_validators,
-            &post_state,
-            block.0.state_root(),
-            block_root.into(),
-            attestation_slot,
-        )
-        .into_iter()
-        .flat_map(|attestations| attestations.into_iter().map(|(att, _subnet)| att))
-        .collect::<Vec<_>>();
+    let attestation_future = if fork_name.electra_enabled() {
+        let single_attestations = harness
+            .make_single_attestations(
+                &all_validators,
+                &post_state,
+                block.0.state_root(),
+                block_root.into(),
+                attestation_slot,
+            )
+            .into_iter()
+            .flat_map(|attestations| attestations.into_iter().map(|(att, _subnet)| att))
+            .collect::<Vec<_>>();
 
-    let fork_name = tester.harness.spec.fork_name_at_slot::<E>(attestation_slot);
-    let attestation_future = tokio::spawn(async move {
-        client
-            .post_beacon_pool_attestations_v2(&attestations, fork_name)
-            .await
-            .expect("attestations should be processed successfully")
-    });
+        let attestations = Either::Right(single_attestations);
+
+        tokio::spawn(async move {
+            client
+                .post_beacon_pool_attestations_v2::<E>(attestations, fork_name)
+                .await
+                .expect("attestations should be processed successfully")
+        })
+    } else {
+        let attestations = harness
+            .make_unaggregated_attestations(
+                &all_validators,
+                &post_state,
+                block.0.state_root(),
+                block_root.into(),
+                attestation_slot,
+            )
+            .into_iter()
+            .flat_map(|attestations| attestations.into_iter().map(|(att, _subnet)| att))
+            .collect::<Vec<_>>();
+
+        tokio::spawn(async move {
+            client
+                .post_beacon_pool_attestations_v1(&attestations)
+                .await
+                .expect("attestations should be processed successfully")
+        })
+    };
 
     // In parallel, apply the block. We need to manually notify the reprocess queue, because the
     // `beacon_chain` does not know about the queue and will not update it for us.
diff --git a/beacon_node/http_api/tests/tests.rs b/beacon_node/http_api/tests/tests.rs
index 7007a14466..bc3159e074 100644
--- a/beacon_node/http_api/tests/tests.rs
+++ b/beacon_node/http_api/tests/tests.rs
@@ -3,6 +3,7 @@ use beacon_chain::{
     test_utils::{AttestationStrategy, BeaconChainHarness, BlockStrategy, EphemeralHarnessType},
     BeaconChain, ChainConfig, StateSkipConfig, WhenSlotSkipped,
 };
+use either::Either;
 use eth2::{
     mixin::{RequestAccept, ResponseForkName, ResponseOptional},
     reqwest::RequestBuilder,
@@ -40,7 +41,8 @@ use tree_hash::TreeHash;
 use types::application_domain::ApplicationDomain;
 use types::{
     attestation::AttestationBase, AggregateSignature, BitList, Domain, EthSpec, ExecutionBlockHash,
-    Hash256, Keypair, MainnetEthSpec, RelativeEpoch, SelectionProof, SignedRoot, Slot,
+    Hash256, Keypair, MainnetEthSpec, RelativeEpoch, SelectionProof, SignedRoot, SingleAttestation,
+    Slot,
 };
 
 type E = MainnetEthSpec;
@@ -71,6 +73,7 @@ struct ApiTester {
     next_block: PublishBlockRequest<E>,
     reorg_block: PublishBlockRequest<E>,
     attestations: Vec<Attestation<E>>,
+    single_attestations: Vec<SingleAttestation>,
     contribution_and_proofs: Vec<SignedContributionAndProof<E>>,
     attester_slashing: AttesterSlashing<E>,
     proposer_slashing: ProposerSlashing,
@@ -203,6 +206,27 @@ impl ApiTester {
             "precondition: attestations for testing"
         );
 
+        let fork_name = harness
+            .chain
+            .spec
+            .fork_name_at_slot::<E>(harness.chain.slot().unwrap());
+
+        let single_attestations = if fork_name.electra_enabled() {
+            harness
+                .get_single_attestations(
+                    &AttestationStrategy::AllValidators,
+                    &head.beacon_state,
+                    head_state_root,
+                    head.beacon_block_root,
+                    harness.chain.slot().unwrap(),
+                )
+                .into_iter()
+                .flat_map(|vec| vec.into_iter().map(|(attestation, _subnet_id)| attestation))
+                .collect::<Vec<_>>()
+        } else {
+            vec![]
+        };
+
         let current_epoch = harness
             .chain
             .slot()
@@ -294,6 +318,7 @@ impl ApiTester {
             next_block,
             reorg_block,
             attestations,
+            single_attestations,
             contribution_and_proofs,
             attester_slashing,
             proposer_slashing,
@@ -381,6 +406,7 @@ impl ApiTester {
             next_block,
             reorg_block,
             attestations,
+            single_attestations: vec![],
             contribution_and_proofs: vec![],
             attester_slashing,
             proposer_slashing,
@@ -1278,7 +1304,7 @@ impl ApiTester {
                 .chain
                 .block_root_at_slot(block.slot(), WhenSlotSkipped::None)
                 .unwrap()
-                .map_or(false, |canonical| block_root == canonical);
+                .is_some_and(|canonical| block_root == canonical);
 
             assert_eq!(result.canonical, canonical, "{:?}", block_id);
             assert_eq!(result.root, block_root, "{:?}", block_id);
@@ -1785,12 +1811,25 @@ impl ApiTester {
         self
     }
 
-    pub async fn test_post_beacon_pool_attestations_valid_v1(mut self) -> Self {
+    pub async fn test_post_beacon_pool_attestations_valid(mut self) -> Self {
         self.client
             .post_beacon_pool_attestations_v1(self.attestations.as_slice())
             .await
             .unwrap();
 
+        let fork_name = self
+            .attestations
+            .first()
+            .map(|att| self.chain.spec.fork_name_at_slot::<E>(att.data().slot))
+            .unwrap();
+
+        let attestations = Either::Left(self.attestations.clone());
+
+        self.client
+            .post_beacon_pool_attestations_v2::<E>(attestations, fork_name)
+            .await
+            .unwrap();
+
         assert!(
             self.network_rx.network_recv.recv().await.is_some(),
             "valid attestation should be sent to network"
@@ -1800,13 +1839,18 @@ impl ApiTester {
     }
 
     pub async fn test_post_beacon_pool_attestations_valid_v2(mut self) -> Self {
+        if self.single_attestations.is_empty() {
+            return self;
+        }
         let fork_name = self
-            .attestations
+            .single_attestations
             .first()
-            .map(|att| self.chain.spec.fork_name_at_slot::<E>(att.data().slot))
+            .map(|att| self.chain.spec.fork_name_at_slot::<E>(att.data.slot))
             .unwrap();
+
+        let attestations = Either::Right(self.single_attestations.clone());
         self.client
-            .post_beacon_pool_attestations_v2(self.attestations.as_slice(), fork_name)
+            .post_beacon_pool_attestations_v2::<E>(attestations, fork_name)
             .await
             .unwrap();
         assert!(
@@ -1854,10 +1898,13 @@ impl ApiTester {
         self
     }
     pub async fn test_post_beacon_pool_attestations_invalid_v2(mut self) -> Self {
+        if self.single_attestations.is_empty() {
+            return self;
+        }
         let mut attestations = Vec::new();
-        for attestation in &self.attestations {
+        for attestation in &self.single_attestations {
             let mut invalid_attestation = attestation.clone();
-            invalid_attestation.data_mut().slot += 1;
+            invalid_attestation.data.slot += 1;
 
             // add both to ensure we only fail on invalid attestations
             attestations.push(attestation.clone());
@@ -1869,10 +1916,10 @@ impl ApiTester {
             .first()
             .map(|att| self.chain.spec.fork_name_at_slot::<E>(att.data().slot))
             .unwrap();
-
+        let attestations = Either::Right(attestations);
         let err_v2 = self
             .client
-            .post_beacon_pool_attestations_v2(attestations.as_slice(), fork_name)
+            .post_beacon_pool_attestations_v2::<E>(attestations, fork_name)
             .await
             .unwrap_err();
 
@@ -1902,7 +1949,7 @@ impl ApiTester {
             .sync_committee_period(&self.chain.spec)
             .unwrap();
 
-        let result = match self
+        match self
             .client
             .get_beacon_light_client_updates::<E>(current_sync_committee_period, 1)
             .await
@@ -1923,7 +1970,6 @@ impl ApiTester {
             .unwrap();
 
         assert_eq!(1, expected.len());
-        assert_eq!(result.clone().unwrap().len(), expected.len());
         self
     }
 
@@ -1948,7 +1994,6 @@ impl ApiTester {
             .get_light_client_bootstrap(&self.chain.store, &block_root, 1u64, &self.chain.spec);
 
         assert!(expected.is_ok());
-
         assert_eq!(result.unwrap().data, expected.unwrap().unwrap().0);
 
         self
@@ -2232,9 +2277,9 @@ impl ApiTester {
     pub async fn test_get_config_spec(self) -> Self {
         let result = self
             .client
-            .get_config_spec::<ConfigAndPresetElectra>()
+            .get_config_spec::<ConfigAndPresetFulu>()
             .await
-            .map(|res| ConfigAndPreset::Electra(res.data))
+            .map(|res| ConfigAndPreset::Fulu(res.data))
             .unwrap();
         let expected = ConfigAndPreset::from_chain_spec::<E>(&self.chain.spec, None);
 
@@ -2331,11 +2376,11 @@ impl ApiTester {
             enr: self.local_enr.clone(),
             p2p_addresses: self.local_enr.multiaddr_p2p_tcp(),
             discovery_addresses: self.local_enr.multiaddr_p2p_udp(),
-            metadata: eth2::types::MetaData {
+            metadata: MetaData::V2(MetaDataV2 {
                 seq_number: 0,
                 attnets: "0x0000000000000000".to_string(),
                 syncnets: "0x00".to_string(),
-            },
+            }),
         };
 
         assert_eq!(result, expected);
@@ -6011,6 +6056,48 @@ impl ApiTester {
         self
     }
 
+    pub async fn test_get_events_electra(self) -> Self {
+        let topics = vec![EventTopic::SingleAttestation];
+        let mut events_future = self
+            .client
+            .get_events::<E>(topics.as_slice())
+            .await
+            .unwrap();
+
+        let expected_attestation_len = self.single_attestations.len();
+
+        let fork_name = self
+            .chain
+            .spec
+            .fork_name_at_slot::<E>(self.chain.slot().unwrap());
+        let attestations = Either::Right(self.single_attestations.clone());
+        self.client
+            .post_beacon_pool_attestations_v2::<E>(attestations, fork_name)
+            .await
+            .unwrap();
+
+        let attestation_events = poll_events(
+            &mut events_future,
+            expected_attestation_len,
+            Duration::from_millis(10000),
+        )
+        .await;
+
+        assert_eq!(
+            attestation_events.as_slice(),
+            self.single_attestations
+                .clone()
+                .into_iter()
+                .map(|single_attestation| EventKind::SingleAttestation(Box::new(
+                    single_attestation
+                )))
+                .collect::<Vec<_>>()
+                .as_slice()
+        );
+
+        self
+    }
+
     pub async fn test_get_events_altair(self) -> Self {
         let topics = vec![EventTopic::ContributionAndProof];
         let mut events_future = self
@@ -6158,6 +6245,20 @@ async fn get_events_altair() {
         .await;
 }
 
+#[tokio::test(flavor = "multi_thread", worker_threads = 2)]
+async fn get_events_electra() {
+    let mut config = ApiTesterConfig::default();
+    config.spec.altair_fork_epoch = Some(Epoch::new(0));
+    config.spec.bellatrix_fork_epoch = Some(Epoch::new(0));
+    config.spec.capella_fork_epoch = Some(Epoch::new(0));
+    config.spec.deneb_fork_epoch = Some(Epoch::new(0));
+    config.spec.electra_fork_epoch = Some(Epoch::new(0));
+    ApiTester::new_from_config(config)
+        .await
+        .test_get_events_electra()
+        .await;
+}
+
 #[tokio::test(flavor = "multi_thread", worker_threads = 2)]
 async fn get_events_from_genesis() {
     ApiTester::new_from_genesis()
@@ -6290,10 +6391,10 @@ async fn post_beacon_blocks_duplicate() {
 }
 
 #[tokio::test(flavor = "multi_thread", worker_threads = 2)]
-async fn beacon_pools_post_attestations_valid_v1() {
+async fn beacon_pools_post_attestations_valid() {
     ApiTester::new()
         .await
-        .test_post_beacon_pool_attestations_valid_v1()
+        .test_post_beacon_pool_attestations_valid()
         .await;
 }
 
diff --git a/beacon_node/http_metrics/Cargo.toml b/beacon_node/http_metrics/Cargo.toml
index d92f986440..9ad073439d 100644
--- a/beacon_node/http_metrics/Cargo.toml
+++ b/beacon_node/http_metrics/Cargo.toml
@@ -7,6 +7,7 @@ edition = { workspace = true }
 
 [dependencies]
 beacon_chain = { workspace = true }
+health_metrics = { workspace = true }
 lighthouse_network = { workspace = true }
 lighthouse_version = { workspace = true }
 malloc_utils = { workspace = true }
diff --git a/beacon_node/http_metrics/src/metrics.rs b/beacon_node/http_metrics/src/metrics.rs
index d751c51e4c..bcfb8e4c9c 100644
--- a/beacon_node/http_metrics/src/metrics.rs
+++ b/beacon_node/http_metrics/src/metrics.rs
@@ -39,7 +39,7 @@ pub fn gather_prometheus_metrics<T: BeaconChainTypes>(
 
     lighthouse_network::scrape_discovery_metrics();
 
-    warp_utils::metrics::scrape_health_metrics();
+    health_metrics::metrics::scrape_health_metrics();
 
     // It's important to ensure these metrics are explicitly enabled in the case that users aren't
     // using glibc and this function causes panics.
diff --git a/beacon_node/lighthouse_network/Cargo.toml b/beacon_node/lighthouse_network/Cargo.toml
index 485f32b37a..3c89ece442 100644
--- a/beacon_node/lighthouse_network/Cargo.toml
+++ b/beacon_node/lighthouse_network/Cargo.toml
@@ -20,7 +20,7 @@ futures = { workspace = true }
 gossipsub = { workspace = true }
 hex = { workspace = true }
 itertools = { workspace = true }
-libp2p-mplex = "0.42"
+libp2p-mplex = "0.43"
 lighthouse_version = { workspace = true }
 lru = { workspace = true }
 lru_cache = { workspace = true }
@@ -50,7 +50,7 @@ unused_port = { workspace = true }
 void = "1.0.2"
 
 [dependencies.libp2p]
-version = "0.54"
+version = "0.55"
 default-features = false
 features = ["identify", "yamux", "noise", "dns", "tcp", "tokio", "plaintext", "secp256k1", "macros", "ecdsa", "metrics", "quic", "upnp"]
 
diff --git a/beacon_node/lighthouse_network/gossipsub/Cargo.toml b/beacon_node/lighthouse_network/gossipsub/Cargo.toml
index 61f5730c08..239caae47a 100644
--- a/beacon_node/lighthouse_network/gossipsub/Cargo.toml
+++ b/beacon_node/lighthouse_network/gossipsub/Cargo.toml
@@ -26,7 +26,7 @@ futures-timer = "3.0.2"
 getrandom = "0.2.12"
 hashlink = { workspace = true }
 hex_fmt = "0.3.0"
-libp2p = { version = "0.54", default-features = false }
+libp2p = { version = "0.55", default-features = false }
 prometheus-client = "0.22.0"
 quick-protobuf = "0.8"
 quick-protobuf-codec = "0.3"
diff --git a/beacon_node/lighthouse_network/gossipsub/src/backoff.rs b/beacon_node/lighthouse_network/gossipsub/src/backoff.rs
index 537d2319c2..0d77e2cd0f 100644
--- a/beacon_node/lighthouse_network/gossipsub/src/backoff.rs
+++ b/beacon_node/lighthouse_network/gossipsub/src/backoff.rs
@@ -124,7 +124,7 @@ impl BackoffStorage {
     pub(crate) fn is_backoff_with_slack(&self, topic: &TopicHash, peer: &PeerId) -> bool {
         self.backoffs
             .get(topic)
-            .map_or(false, |m| m.contains_key(peer))
+            .is_some_and(|m| m.contains_key(peer))
     }
 
     pub(crate) fn get_backoff_time(&self, topic: &TopicHash, peer: &PeerId) -> Option<Instant> {
diff --git a/beacon_node/lighthouse_network/gossipsub/src/behaviour.rs b/beacon_node/lighthouse_network/gossipsub/src/behaviour.rs
index c4e20e4397..7eb35cc49b 100644
--- a/beacon_node/lighthouse_network/gossipsub/src/behaviour.rs
+++ b/beacon_node/lighthouse_network/gossipsub/src/behaviour.rs
@@ -1770,8 +1770,7 @@ where
         // reject messages claiming to be from ourselves but not locally published
         let self_published = !self.config.allow_self_origin()
             && if let Some(own_id) = self.publish_config.get_own_id() {
-                own_id != propagation_source
-                    && raw_message.source.as_ref().map_or(false, |s| s == own_id)
+                own_id != propagation_source && raw_message.source.as_ref() == Some(own_id)
             } else {
                 self.published_message_ids.contains(msg_id)
             };
@@ -1842,6 +1841,30 @@ where
                 peer_score.duplicated_message(propagation_source, &msg_id, &message.topic);
             }
             self.mcache.observe_duplicate(&msg_id, propagation_source);
+            // track metrics for the source of the duplicates
+            if let Some(metrics) = self.metrics.as_mut() {
+                if self
+                    .mesh
+                    .get(&message.topic)
+                    .is_some_and(|peers| peers.contains(propagation_source))
+                {
+                    // duplicate was received from a mesh peer
+                    metrics.mesh_duplicates(&message.topic);
+                } else if self
+                    .gossip_promises
+                    .contains_peer(&msg_id, propagation_source)
+                {
+                    // duplicate was received from an iwant request
+                    metrics.iwant_duplicates(&message.topic);
+                } else {
+                    tracing::warn!(
+                        messsage=%msg_id,
+                        peer=%propagation_source,
+                        topic=%message.topic,
+                        "Peer should not have sent message"
+                    );
+                }
+            }
             return;
         }
 
diff --git a/beacon_node/lighthouse_network/gossipsub/src/gossip_promises.rs b/beacon_node/lighthouse_network/gossipsub/src/gossip_promises.rs
index 3f72709245..ce1dee2a72 100644
--- a/beacon_node/lighthouse_network/gossipsub/src/gossip_promises.rs
+++ b/beacon_node/lighthouse_network/gossipsub/src/gossip_promises.rs
@@ -41,6 +41,13 @@ impl GossipPromises {
         self.promises.contains_key(message)
     }
 
+    /// Returns true if the message id exists in the promises and contains the given peer.
+    pub(crate) fn contains_peer(&self, message: &MessageId, peer: &PeerId) -> bool {
+        self.promises
+            .get(message)
+            .is_some_and(|peers| peers.contains_key(peer))
+    }
+
     ///Get the peers we sent IWANT the input message id.
     pub(crate) fn peers_for_message(&self, message_id: &MessageId) -> Vec<PeerId> {
         self.promises
diff --git a/beacon_node/lighthouse_network/gossipsub/src/handler.rs b/beacon_node/lighthouse_network/gossipsub/src/handler.rs
index d89013eb2f..0f25db6e3d 100644
--- a/beacon_node/lighthouse_network/gossipsub/src/handler.rs
+++ b/beacon_node/lighthouse_network/gossipsub/src/handler.rs
@@ -194,7 +194,6 @@ impl EnabledHandler {
         &mut self,
         FullyNegotiatedOutbound { protocol, .. }: FullyNegotiatedOutbound<
             <Handler as ConnectionHandler>::OutboundProtocol,
-            <Handler as ConnectionHandler>::OutboundOpenInfo,
         >,
     ) {
         let (substream, peer_kind) = protocol;
@@ -217,7 +216,7 @@ impl EnabledHandler {
     ) -> Poll<
         ConnectionHandlerEvent<
             <Handler as ConnectionHandler>::OutboundProtocol,
-            <Handler as ConnectionHandler>::OutboundOpenInfo,
+            (),
             <Handler as ConnectionHandler>::ToBehaviour,
         >,
     > {
@@ -423,7 +422,7 @@ impl ConnectionHandler for Handler {
     type OutboundOpenInfo = ();
     type OutboundProtocol = ProtocolConfig;
 
-    fn listen_protocol(&self) -> SubstreamProtocol<Self::InboundProtocol, Self::InboundOpenInfo> {
+    fn listen_protocol(&self) -> SubstreamProtocol<Self::InboundProtocol, ()> {
         match self {
             Handler::Enabled(handler) => {
                 SubstreamProtocol::new(either::Either::Left(handler.listen_protocol.clone()), ())
@@ -458,9 +457,7 @@ impl ConnectionHandler for Handler {
     fn poll(
         &mut self,
         cx: &mut Context<'_>,
-    ) -> Poll<
-        ConnectionHandlerEvent<Self::OutboundProtocol, Self::OutboundOpenInfo, Self::ToBehaviour>,
-    > {
+    ) -> Poll<ConnectionHandlerEvent<Self::OutboundProtocol, (), Self::ToBehaviour>> {
         match self {
             Handler::Enabled(handler) => handler.poll(cx),
             Handler::Disabled(DisabledHandler::ProtocolUnsupported { peer_kind_sent }) => {
@@ -479,12 +476,7 @@ impl ConnectionHandler for Handler {
 
     fn on_connection_event(
         &mut self,
-        event: ConnectionEvent<
-            Self::InboundProtocol,
-            Self::OutboundProtocol,
-            Self::InboundOpenInfo,
-            Self::OutboundOpenInfo,
-        >,
+        event: ConnectionEvent<Self::InboundProtocol, Self::OutboundProtocol>,
     ) {
         match self {
             Handler::Enabled(handler) => {
@@ -521,7 +513,7 @@ impl ConnectionHandler for Handler {
                     }) => match protocol {
                         Either::Left(protocol) => handler.on_fully_negotiated_inbound(protocol),
                         #[allow(unreachable_patterns)]
-                        Either::Right(v) => void::unreachable(v),
+                        Either::Right(v) => libp2p::core::util::unreachable(v),
                     },
                     ConnectionEvent::FullyNegotiatedOutbound(fully_negotiated_outbound) => {
                         handler.on_fully_negotiated_outbound(fully_negotiated_outbound)
diff --git a/beacon_node/lighthouse_network/gossipsub/src/metrics.rs b/beacon_node/lighthouse_network/gossipsub/src/metrics.rs
index d3ca6c299e..2989f95a26 100644
--- a/beacon_node/lighthouse_network/gossipsub/src/metrics.rs
+++ b/beacon_node/lighthouse_network/gossipsub/src/metrics.rs
@@ -194,6 +194,12 @@ pub(crate) struct Metrics {
     /// Number of full messages we received that we previously sent a IDONTWANT for.
     idontwant_messages_ignored_per_topic: Family<TopicHash, Counter>,
 
+    /// Count of duplicate messages we have received from mesh peers for a given topic.
+    mesh_duplicates: Family<TopicHash, Counter>,
+
+    /// Count of duplicate messages we have received from by requesting them over iwant for a given topic.
+    iwant_duplicates: Family<TopicHash, Counter>,
+
     /// The size of the priority queue.
     priority_queue_size: Histogram,
     /// The size of the non-priority queue.
@@ -359,6 +365,16 @@ impl Metrics {
             "IDONTWANT messages that were sent but we received the full message regardless"
         );
 
+        let mesh_duplicates = register_family!(
+            "mesh_duplicates_per_topic",
+            "Count of duplicate messages received from mesh peers per topic"
+        );
+
+        let iwant_duplicates = register_family!(
+            "iwant_duplicates_per_topic",
+            "Count of duplicate messages received from non-mesh peers that we sent iwants for"
+        );
+
         let idontwant_bytes = {
             let metric = Counter::default();
             registry.register(
@@ -425,6 +441,8 @@ impl Metrics {
             idontwant_msgs_ids,
             idontwant_messages_sent_per_topic,
             idontwant_messages_ignored_per_topic,
+            mesh_duplicates,
+            iwant_duplicates,
             priority_queue_size,
             non_priority_queue_size,
         }
@@ -597,6 +615,20 @@ impl Metrics {
         }
     }
 
+    /// Register a duplicate message received from a mesh peer.
+    pub(crate) fn mesh_duplicates(&mut self, topic: &TopicHash) {
+        if self.register_topic(topic).is_ok() {
+            self.mesh_duplicates.get_or_create(topic).inc();
+        }
+    }
+
+    /// Register a duplicate message received from a non-mesh peer on an iwant request.
+    pub(crate) fn iwant_duplicates(&mut self, topic: &TopicHash) {
+        if self.register_topic(topic).is_ok() {
+            self.iwant_duplicates.get_or_create(topic).inc();
+        }
+    }
+
     pub(crate) fn register_msg_validation(
         &mut self,
         topic: &TopicHash,
diff --git a/beacon_node/lighthouse_network/src/config.rs b/beacon_node/lighthouse_network/src/config.rs
index 21f3dc830f..55c1dbf491 100644
--- a/beacon_node/lighthouse_network/src/config.rs
+++ b/beacon_node/lighthouse_network/src/config.rs
@@ -116,7 +116,8 @@ pub struct Config {
     pub network_load: u8,
 
     /// Indicates if the user has set the network to be in private mode. Currently this
-    /// prevents sending client identifying information over identify.
+    /// prevents sending client identifying information over identify and prevents
+    /// EIP-7636 indentifiable information being provided in the ENR.
     pub private: bool,
 
     /// Shutdown beacon node after sync is completed.
@@ -166,7 +167,7 @@ impl Config {
             tcp_port,
         });
         self.discv5_config.listen_config = discv5::ListenConfig::from_ip(addr.into(), disc_port);
-        self.discv5_config.table_filter = |enr| enr.ip4().as_ref().map_or(false, is_global_ipv4)
+        self.discv5_config.table_filter = |enr| enr.ip4().as_ref().is_some_and(is_global_ipv4)
     }
 
     /// Sets the listening address to use an ipv6 address. The discv5 ip_mode and table filter is
@@ -187,7 +188,7 @@ impl Config {
         });
 
         self.discv5_config.listen_config = discv5::ListenConfig::from_ip(addr.into(), disc_port);
-        self.discv5_config.table_filter = |enr| enr.ip6().as_ref().map_or(false, is_global_ipv6)
+        self.discv5_config.table_filter = |enr| enr.ip6().as_ref().is_some_and(is_global_ipv6)
     }
 
     /// Sets the listening address to use both an ipv4 and ipv6 address. The discv5 ip_mode and
@@ -317,7 +318,7 @@ impl Default for Config {
             .filter_rate_limiter(filter_rate_limiter)
             .filter_max_bans_per_ip(Some(5))
             .filter_max_nodes_per_ip(Some(10))
-            .table_filter(|enr| enr.ip4().map_or(false, |ip| is_global_ipv4(&ip))) // Filter non-global IPs
+            .table_filter(|enr| enr.ip4().is_some_and(|ip| is_global_ipv4(&ip))) // Filter non-global IPs
             .ban_duration(Some(Duration::from_secs(3600)))
             .ping_interval(Duration::from_secs(300))
             .build();
diff --git a/beacon_node/lighthouse_network/src/discovery/enr.rs b/beacon_node/lighthouse_network/src/discovery/enr.rs
index ce29480ffd..8067711954 100644
--- a/beacon_node/lighthouse_network/src/discovery/enr.rs
+++ b/beacon_node/lighthouse_network/src/discovery/enr.rs
@@ -8,6 +8,7 @@ use crate::types::{Enr, EnrAttestationBitfield, EnrSyncCommitteeBitfield};
 use crate::NetworkConfig;
 use alloy_rlp::bytes::Bytes;
 use libp2p::identity::Keypair;
+use lighthouse_version::{client_name, version};
 use slog::{debug, warn};
 use ssz::{Decode, Encode};
 use ssz_types::BitVector;
@@ -25,8 +26,8 @@ pub const ETH2_ENR_KEY: &str = "eth2";
 pub const ATTESTATION_BITFIELD_ENR_KEY: &str = "attnets";
 /// The ENR field specifying the sync committee subnet bitfield.
 pub const SYNC_COMMITTEE_BITFIELD_ENR_KEY: &str = "syncnets";
-/// The ENR field specifying the peerdas custody subnet count.
-pub const PEERDAS_CUSTODY_SUBNET_COUNT_ENR_KEY: &str = "csc";
+/// The ENR field specifying the peerdas custody group count.
+pub const PEERDAS_CUSTODY_GROUP_COUNT_ENR_KEY: &str = "cgc";
 
 /// Extension trait for ENR's within Eth2.
 pub trait Eth2Enr {
@@ -38,8 +39,8 @@ pub trait Eth2Enr {
         &self,
     ) -> Result<EnrSyncCommitteeBitfield<E>, &'static str>;
 
-    /// The peerdas custody subnet count associated with the ENR.
-    fn custody_subnet_count<E: EthSpec>(&self, spec: &ChainSpec) -> Result<u64, &'static str>;
+    /// The peerdas custody group count associated with the ENR.
+    fn custody_group_count<E: EthSpec>(&self, spec: &ChainSpec) -> Result<u64, &'static str>;
 
     fn eth2(&self) -> Result<EnrForkId, &'static str>;
 }
@@ -67,16 +68,16 @@ impl Eth2Enr for Enr {
             .map_err(|_| "Could not decode the ENR syncnets bitfield")
     }
 
-    fn custody_subnet_count<E: EthSpec>(&self, spec: &ChainSpec) -> Result<u64, &'static str> {
-        let csc = self
-            .get_decodable::<u64>(PEERDAS_CUSTODY_SUBNET_COUNT_ENR_KEY)
-            .ok_or("ENR custody subnet count non-existent")?
-            .map_err(|_| "Could not decode the ENR custody subnet count")?;
+    fn custody_group_count<E: EthSpec>(&self, spec: &ChainSpec) -> Result<u64, &'static str> {
+        let cgc = self
+            .get_decodable::<u64>(PEERDAS_CUSTODY_GROUP_COUNT_ENR_KEY)
+            .ok_or("ENR custody group count non-existent")?
+            .map_err(|_| "Could not decode the ENR custody group count")?;
 
-        if csc >= spec.custody_requirement && csc <= spec.data_column_sidecar_subnet_count {
-            Ok(csc)
+        if (spec.custody_requirement..=spec.number_of_custody_groups).contains(&cgc) {
+            Ok(cgc)
         } else {
-            Err("Invalid custody subnet count in ENR")
+            Err("Invalid custody group count in ENR")
         }
     }
 
@@ -188,6 +189,11 @@ pub fn build_enr<E: EthSpec>(
         builder.udp6(udp6_port.get());
     }
 
+    // Add EIP 7636 client information
+    if !config.private {
+        builder.client_info(client_name().to_string(), version().to_string(), None);
+    }
+
     // Add QUIC fields to the ENR.
     // Since QUIC is used as an alternative transport for the libp2p protocols,
     // the related fields should only be added when both QUIC and libp2p are enabled
@@ -253,14 +259,14 @@ pub fn build_enr<E: EthSpec>(
         &bitfield.as_ssz_bytes().into(),
     );
 
-    // only set `csc` if PeerDAS fork epoch has been scheduled
+    // only set `cgc` if PeerDAS fork epoch has been scheduled
     if spec.is_peer_das_scheduled() {
-        let custody_subnet_count = if config.subscribe_all_data_column_subnets {
-            spec.data_column_sidecar_subnet_count
+        let custody_group_count = if config.subscribe_all_data_column_subnets {
+            spec.number_of_custody_groups
         } else {
             spec.custody_requirement
         };
-        builder.add_value(PEERDAS_CUSTODY_SUBNET_COUNT_ENR_KEY, &custody_subnet_count);
+        builder.add_value(PEERDAS_CUSTODY_GROUP_COUNT_ENR_KEY, &custody_group_count);
     }
 
     builder
@@ -287,11 +293,11 @@ fn compare_enr(local_enr: &Enr, disk_enr: &Enr) -> bool {
         && (local_enr.udp4().is_none() || local_enr.udp4() == disk_enr.udp4())
         && (local_enr.udp6().is_none() || local_enr.udp6() == disk_enr.udp6())
         // we need the ATTESTATION_BITFIELD_ENR_KEY and SYNC_COMMITTEE_BITFIELD_ENR_KEY and
-        // PEERDAS_CUSTODY_SUBNET_COUNT_ENR_KEY key to match, otherwise we use a new ENR. This will
+        // PEERDAS_CUSTODY_GROUP_COUNT_ENR_KEY key to match, otherwise we use a new ENR. This will
         // likely only be true for non-validating nodes.
         && local_enr.get_decodable::<Bytes>(ATTESTATION_BITFIELD_ENR_KEY) == disk_enr.get_decodable(ATTESTATION_BITFIELD_ENR_KEY)
         && local_enr.get_decodable::<Bytes>(SYNC_COMMITTEE_BITFIELD_ENR_KEY) == disk_enr.get_decodable(SYNC_COMMITTEE_BITFIELD_ENR_KEY)
-        && local_enr.get_decodable::<Bytes>(PEERDAS_CUSTODY_SUBNET_COUNT_ENR_KEY) == disk_enr.get_decodable(PEERDAS_CUSTODY_SUBNET_COUNT_ENR_KEY)
+        && local_enr.get_decodable::<Bytes>(PEERDAS_CUSTODY_GROUP_COUNT_ENR_KEY) == disk_enr.get_decodable(PEERDAS_CUSTODY_GROUP_COUNT_ENR_KEY)
 }
 
 /// Loads enr from the given directory
@@ -333,9 +339,9 @@ mod test {
 
     type E = MainnetEthSpec;
 
-    fn make_eip7594_spec() -> ChainSpec {
+    fn make_fulu_spec() -> ChainSpec {
         let mut spec = E::default_spec();
-        spec.eip7594_fork_epoch = Some(Epoch::new(10));
+        spec.fulu_fork_epoch = Some(Epoch::new(10));
         spec
     }
 
@@ -348,33 +354,33 @@ mod test {
     }
 
     #[test]
-    fn custody_subnet_count_default() {
+    fn custody_group_count_default() {
         let config = NetworkConfig {
             subscribe_all_data_column_subnets: false,
             ..NetworkConfig::default()
         };
-        let spec = make_eip7594_spec();
+        let spec = make_fulu_spec();
 
         let enr = build_enr_with_config(config, &spec).0;
 
         assert_eq!(
-            enr.custody_subnet_count::<E>(&spec).unwrap(),
+            enr.custody_group_count::<E>(&spec).unwrap(),
             spec.custody_requirement,
         );
     }
 
     #[test]
-    fn custody_subnet_count_all() {
+    fn custody_group_count_all() {
         let config = NetworkConfig {
             subscribe_all_data_column_subnets: true,
             ..NetworkConfig::default()
         };
-        let spec = make_eip7594_spec();
+        let spec = make_fulu_spec();
         let enr = build_enr_with_config(config, &spec).0;
 
         assert_eq!(
-            enr.custody_subnet_count::<E>(&spec).unwrap(),
-            spec.data_column_sidecar_subnet_count,
+            enr.custody_group_count::<E>(&spec).unwrap(),
+            spec.number_of_custody_groups,
         );
     }
 
diff --git a/beacon_node/lighthouse_network/src/discovery/mod.rs b/beacon_node/lighthouse_network/src/discovery/mod.rs
index 578bb52b51..33c7775ae2 100644
--- a/beacon_node/lighthouse_network/src/discovery/mod.rs
+++ b/beacon_node/lighthouse_network/src/discovery/mod.rs
@@ -994,7 +994,7 @@ impl<E: EthSpec> NetworkBehaviour for Discovery<E> {
         &mut self,
         _peer_id: PeerId,
         _connection_id: ConnectionId,
-        _event: void::Void,
+        _event: std::convert::Infallible,
     ) {
     }
 
diff --git a/beacon_node/lighthouse_network/src/discovery/subnet_predicate.rs b/beacon_node/lighthouse_network/src/discovery/subnet_predicate.rs
index 02ff0cc3ca..400a0c2d56 100644
--- a/beacon_node/lighthouse_network/src/discovery/subnet_predicate.rs
+++ b/beacon_node/lighthouse_network/src/discovery/subnet_predicate.rs
@@ -1,10 +1,10 @@
 //! The subnet predicate used for searching for a particular subnet.
 use super::*;
 use crate::types::{EnrAttestationBitfield, EnrSyncCommitteeBitfield};
-use itertools::Itertools;
 use slog::trace;
 use std::ops::Deref;
-use types::{ChainSpec, DataColumnSubnetId};
+use types::data_column_custody_group::compute_subnets_for_node;
+use types::ChainSpec;
 
 /// Returns the predicate for a given subnet.
 pub fn subnet_predicate<E>(
@@ -35,15 +35,11 @@ where
                 .unwrap_or(false),
             Subnet::SyncCommittee(s) => sync_committee_bitfield
                 .as_ref()
-                .map_or(false, |b| b.get(*s.deref() as usize).unwrap_or(false)),
+                .is_ok_and(|b| b.get(*s.deref() as usize).unwrap_or(false)),
             Subnet::DataColumn(s) => {
-                if let Ok(custody_subnet_count) = enr.custody_subnet_count::<E>(&spec) {
-                    DataColumnSubnetId::compute_custody_subnets::<E>(
-                        enr.node_id().raw(),
-                        custody_subnet_count,
-                        &spec,
-                    )
-                    .map_or(false, |mut subnets| subnets.contains(s))
+                if let Ok(custody_group_count) = enr.custody_group_count::<E>(&spec) {
+                    compute_subnets_for_node(enr.node_id().raw(), custody_group_count, &spec)
+                        .is_ok_and(|subnets| subnets.contains(s))
                 } else {
                     false
                 }
diff --git a/beacon_node/lighthouse_network/src/metrics.rs b/beacon_node/lighthouse_network/src/metrics.rs
index cb9c007b91..b36cb8075d 100644
--- a/beacon_node/lighthouse_network/src/metrics.rs
+++ b/beacon_node/lighthouse_network/src/metrics.rs
@@ -93,11 +93,11 @@ pub static PEERS_PER_CLIENT: LazyLock<Result<IntGaugeVec>> = LazyLock::new(|| {
     )
 });
 
-pub static PEERS_PER_CUSTODY_SUBNET_COUNT: LazyLock<Result<IntGaugeVec>> = LazyLock::new(|| {
+pub static PEERS_PER_CUSTODY_GROUP_COUNT: LazyLock<Result<IntGaugeVec>> = LazyLock::new(|| {
     try_create_int_gauge_vec(
-        "peers_per_custody_subnet_count",
-        "The current count of peers by custody subnet count",
-        &["custody_subnet_count"],
+        "peers_per_custody_group_count",
+        "The current count of peers by custody group count",
+        &["custody_group_count"],
     )
 });
 
diff --git a/beacon_node/lighthouse_network/src/peer_manager/mod.rs b/beacon_node/lighthouse_network/src/peer_manager/mod.rs
index 4df2566dac..07c4be7959 100644
--- a/beacon_node/lighthouse_network/src/peer_manager/mod.rs
+++ b/beacon_node/lighthouse_network/src/peer_manager/mod.rs
@@ -34,6 +34,9 @@ pub use peerdb::sync_status::{SyncInfo, SyncStatus};
 use std::collections::{hash_map::Entry, HashMap, HashSet};
 use std::net::IpAddr;
 use strum::IntoEnumIterator;
+use types::data_column_custody_group::{
+    compute_subnets_from_custody_group, get_custody_groups, CustodyIndex,
+};
 
 pub mod config;
 mod network_behaviour;
@@ -63,6 +66,8 @@ pub const MIN_OUTBOUND_ONLY_FACTOR: f32 = 0.2;
 /// limit is 55, and we are at 55 peers, the following parameter provisions a few more slots of
 /// dialing priority peers we need for validator duties.
 pub const PRIORITY_PEER_EXCESS: f32 = 0.2;
+/// The numbre of inbound libp2p peers we have seen before we consider our NAT to be open.
+pub const LIBP2P_NAT_OPEN_THRESHOLD: usize = 3;
 
 /// The main struct that handles peer's reputation and connection status.
 pub struct PeerManager<E: EthSpec> {
@@ -99,6 +104,8 @@ pub struct PeerManager<E: EthSpec> {
     /// discovery queries for subnet peers if we disconnect from existing sync
     /// committee subnet peers.
     sync_committee_subnets: HashMap<SyncSubnetId, Instant>,
+    /// A mapping of all custody groups to column subnets to avoid re-computation.
+    subnets_by_custody_group: HashMap<u64, Vec<DataColumnSubnetId>>,
     /// The heartbeat interval to perform routine maintenance.
     heartbeat: tokio::time::Interval,
     /// Keeps track of whether the discovery service is enabled or not.
@@ -158,6 +165,21 @@ impl<E: EthSpec> PeerManager<E> {
         // Set up the peer manager heartbeat interval
         let heartbeat = tokio::time::interval(tokio::time::Duration::from_secs(HEARTBEAT_INTERVAL));
 
+        // Compute subnets for all custody groups
+        let subnets_by_custody_group = if network_globals.spec.is_peer_das_scheduled() {
+            (0..network_globals.spec.number_of_custody_groups)
+                .map(|custody_index| {
+                    let subnets =
+                        compute_subnets_from_custody_group(custody_index, &network_globals.spec)
+                            .expect("Should compute subnets for all custody groups")
+                            .collect();
+                    (custody_index, subnets)
+                })
+                .collect::<HashMap<_, Vec<DataColumnSubnetId>>>()
+        } else {
+            HashMap::new()
+        };
+
         Ok(PeerManager {
             network_globals,
             events: SmallVec::new(),
@@ -168,6 +190,7 @@ impl<E: EthSpec> PeerManager<E> {
             target_peers: target_peer_count,
             temporary_banned_peers: LRUTimeCache::new(PEER_RECONNECTION_TIMEOUT),
             sync_committee_subnets: Default::default(),
+            subnets_by_custody_group,
             heartbeat,
             discovery_enabled,
             metrics_enabled,
@@ -709,22 +732,39 @@ impl<E: EthSpec> PeerManager<E> {
                     "peer_id" => %peer_id, "new_seq_no" => meta_data.seq_number());
             }
 
-            let custody_subnet_count_opt = meta_data.custody_subnet_count().copied().ok();
+            let custody_group_count_opt = meta_data.custody_group_count().copied().ok();
             peer_info.set_meta_data(meta_data);
 
             if self.network_globals.spec.is_peer_das_scheduled() {
                 // Gracefully ignore metadata/v2 peers. Potentially downscore after PeerDAS to
                 // prioritize PeerDAS peers.
-                if let Some(custody_subnet_count) = custody_subnet_count_opt {
-                    match self.compute_peer_custody_subnets(peer_id, custody_subnet_count) {
-                        Ok(custody_subnets) => {
+                if let Some(custody_group_count) = custody_group_count_opt {
+                    match self.compute_peer_custody_groups(peer_id, custody_group_count) {
+                        Ok(custody_groups) => {
+                            let custody_subnets = custody_groups
+                                .into_iter()
+                                .flat_map(|custody_index| {
+                                    self.subnets_by_custody_group
+                                        .get(&custody_index)
+                                        .cloned()
+                                        .unwrap_or_else(|| {
+                                            warn!(
+                                                self.log,
+                                                "Custody group not found in subnet mapping";
+                                                "custody_index" => custody_index,
+                                                "peer_id" => %peer_id
+                                            );
+                                            vec![]
+                                        })
+                                })
+                                .collect();
                             peer_info.set_custody_subnets(custody_subnets);
                         }
                         Err(err) => {
-                            debug!(self.log, "Unable to compute peer custody subnets from metadata";
+                            debug!(self.log, "Unable to compute peer custody groups from metadata";
                                 "info" => "Sending goodbye to peer",
                                 "peer_id" => %peer_id,
-                                "custody_subnet_count" => custody_subnet_count,
+                                "custody_group_count" => custody_group_count,
                                 "error" => ?err,
                             );
                             invalid_meta_data = true;
@@ -1307,8 +1347,10 @@ impl<E: EthSpec> PeerManager<E> {
     fn update_peer_count_metrics(&self) {
         let mut peers_connected = 0;
         let mut clients_per_peer = HashMap::new();
-        let mut peers_connected_mutli: HashMap<(&str, &str), i32> = HashMap::new();
-        let mut peers_per_custody_subnet_count: HashMap<u64, i64> = HashMap::new();
+        let mut inbound_ipv4_peers_connected: usize = 0;
+        let mut inbound_ipv6_peers_connected: usize = 0;
+        let mut peers_connected_multi: HashMap<(&str, &str), i32> = HashMap::new();
+        let mut peers_per_custody_group_count: HashMap<u64, i64> = HashMap::new();
 
         for (_, peer_info) in self.network_globals.peers.read().connected_peers() {
             peers_connected += 1;
@@ -1336,25 +1378,48 @@ impl<E: EthSpec> PeerManager<E> {
                     })
                 })
                 .unwrap_or("unknown");
-            *peers_connected_mutli
+            *peers_connected_multi
                 .entry((direction, transport))
                 .or_default() += 1;
 
             if let Some(MetaData::V3(meta_data)) = peer_info.meta_data() {
-                *peers_per_custody_subnet_count
-                    .entry(meta_data.custody_subnet_count)
+                *peers_per_custody_group_count
+                    .entry(meta_data.custody_group_count)
                     .or_default() += 1;
             }
+            // Check if incoming peer is ipv4
+            if peer_info.is_incoming_ipv4_connection() {
+                inbound_ipv4_peers_connected += 1;
+            }
+
+            // Check if incoming peer is ipv6
+            if peer_info.is_incoming_ipv6_connection() {
+                inbound_ipv6_peers_connected += 1;
+            }
+        }
+
+        // Set ipv4 nat_open metric flag if threshold of peercount is met, unset if below threshold
+        if inbound_ipv4_peers_connected >= LIBP2P_NAT_OPEN_THRESHOLD {
+            metrics::set_gauge_vec(&metrics::NAT_OPEN, &["libp2p_ipv4"], 1);
+        } else {
+            metrics::set_gauge_vec(&metrics::NAT_OPEN, &["libp2p_ipv4"], 0);
+        }
+
+        // Set ipv6 nat_open metric flag if threshold of peercount is met, unset if below threshold
+        if inbound_ipv6_peers_connected >= LIBP2P_NAT_OPEN_THRESHOLD {
+            metrics::set_gauge_vec(&metrics::NAT_OPEN, &["libp2p_ipv6"], 1);
+        } else {
+            metrics::set_gauge_vec(&metrics::NAT_OPEN, &["libp2p_ipv6"], 0);
         }
 
         // PEERS_CONNECTED
         metrics::set_gauge(&metrics::PEERS_CONNECTED, peers_connected);
 
-        // CUSTODY_SUBNET_COUNT
-        for (custody_subnet_count, peer_count) in peers_per_custody_subnet_count.into_iter() {
+        // CUSTODY_GROUP_COUNT
+        for (custody_group_count, peer_count) in peers_per_custody_group_count.into_iter() {
             metrics::set_gauge_vec(
-                &metrics::PEERS_PER_CUSTODY_SUBNET_COUNT,
-                &[&custody_subnet_count.to_string()],
+                &metrics::PEERS_PER_CUSTODY_GROUP_COUNT,
+                &[&custody_group_count.to_string()],
                 peer_count,
             )
         }
@@ -1375,7 +1440,7 @@ impl<E: EthSpec> PeerManager<E> {
                 metrics::set_gauge_vec(
                     &metrics::PEERS_CONNECTED_MULTI,
                     &[direction, transport],
-                    *peers_connected_mutli
+                    *peers_connected_multi
                         .get(&(direction, transport))
                         .unwrap_or(&0) as i64,
                 );
@@ -1383,43 +1448,27 @@ impl<E: EthSpec> PeerManager<E> {
         }
     }
 
-    fn compute_peer_custody_subnets(
+    fn compute_peer_custody_groups(
         &self,
         peer_id: &PeerId,
-        custody_subnet_count: u64,
-    ) -> Result<HashSet<DataColumnSubnetId>, String> {
+        custody_group_count: u64,
+    ) -> Result<HashSet<CustodyIndex>, String> {
         // If we don't have a node id, we cannot compute the custody duties anyway
         let node_id = peer_id_to_node_id(peer_id)?;
         let spec = &self.network_globals.spec;
 
-        if !(spec.custody_requirement..=spec.data_column_sidecar_subnet_count)
-            .contains(&custody_subnet_count)
+        if !(spec.custody_requirement..=spec.number_of_custody_groups)
+            .contains(&custody_group_count)
         {
-            return Err("Invalid custody subnet count in metadata: out of range".to_string());
+            return Err("Invalid custody group count in metadata: out of range".to_string());
         }
 
-        let custody_subnets = DataColumnSubnetId::compute_custody_subnets::<E>(
-            node_id.raw(),
-            custody_subnet_count,
-            spec,
-        )
-        .map(|subnets| subnets.collect())
-        .unwrap_or_else(|e| {
-            // This is an unreachable scenario unless there's a bug, as we've validated the csc
-            // just above.
-            error!(
-                self.log,
-                "Computing peer custody subnets failed unexpectedly";
-                "info" => "Falling back to default custody requirement subnets",
-                "peer_id" => %peer_id,
-                "custody_subnet_count" => custody_subnet_count,
-                "error" => ?e
-            );
-            DataColumnSubnetId::compute_custody_requirement_subnets::<E>(node_id.raw(), spec)
-                .collect()
-        });
-
-        Ok(custody_subnets)
+        get_custody_groups(node_id.raw(), custody_group_count, spec).map_err(|e| {
+            format!(
+                "Error computing peer custody groups for node {} with cgc={}: {:?}",
+                node_id, custody_group_count, e
+            )
+        })
     }
 }
 
diff --git a/beacon_node/lighthouse_network/src/peer_manager/network_behaviour.rs b/beacon_node/lighthouse_network/src/peer_manager/network_behaviour.rs
index 9fd059df85..abafb200be 100644
--- a/beacon_node/lighthouse_network/src/peer_manager/network_behaviour.rs
+++ b/beacon_node/lighthouse_network/src/peer_manager/network_behaviour.rs
@@ -37,7 +37,10 @@ impl<E: EthSpec> NetworkBehaviour for PeerManager<E> {
         // no events from the dummy handler
     }
 
-    fn poll(&mut self, cx: &mut Context<'_>) -> Poll<ToSwarm<Self::ToSwarm, void::Void>> {
+    fn poll(
+        &mut self,
+        cx: &mut Context<'_>,
+    ) -> Poll<ToSwarm<Self::ToSwarm, std::convert::Infallible>> {
         // perform the heartbeat when necessary
         while self.heartbeat.poll_tick(cx).is_ready() {
             self.heartbeat();
diff --git a/beacon_node/lighthouse_network/src/peer_manager/peerdb.rs b/beacon_node/lighthouse_network/src/peer_manager/peerdb.rs
index d2effd4d03..37cb5df6ea 100644
--- a/beacon_node/lighthouse_network/src/peer_manager/peerdb.rs
+++ b/beacon_node/lighthouse_network/src/peer_manager/peerdb.rs
@@ -1,4 +1,4 @@
-use crate::discovery::enr::PEERDAS_CUSTODY_SUBNET_COUNT_ENR_KEY;
+use crate::discovery::enr::PEERDAS_CUSTODY_GROUP_COUNT_ENR_KEY;
 use crate::discovery::{peer_id_to_node_id, CombinedKey};
 use crate::{metrics, multiaddr::Multiaddr, types::Subnet, Enr, EnrExt, Gossipsub, PeerId};
 use itertools::Itertools;
@@ -13,6 +13,7 @@ use std::{
     fmt::Formatter,
 };
 use sync_status::SyncStatus;
+use types::data_column_custody_group::compute_subnets_for_node;
 use types::{ChainSpec, DataColumnSubnetId, EthSpec};
 
 pub mod client;
@@ -695,8 +696,8 @@ impl<E: EthSpec> PeerDB<E> {
 
         if supernode {
             enr.insert(
-                PEERDAS_CUSTODY_SUBNET_COUNT_ENR_KEY,
-                &spec.data_column_sidecar_subnet_count,
+                PEERDAS_CUSTODY_GROUP_COUNT_ENR_KEY,
+                &spec.number_of_custody_groups,
                 &enr_key,
             )
             .expect("u64 can be encoded");
@@ -714,19 +715,14 @@ impl<E: EthSpec> PeerDB<E> {
         if supernode {
             let peer_info = self.peers.get_mut(&peer_id).expect("peer exists");
             let all_subnets = (0..spec.data_column_sidecar_subnet_count)
-                .map(|csc| csc.into())
+                .map(|subnet_id| subnet_id.into())
                 .collect();
             peer_info.set_custody_subnets(all_subnets);
         } else {
             let peer_info = self.peers.get_mut(&peer_id).expect("peer exists");
             let node_id = peer_id_to_node_id(&peer_id).expect("convert peer_id to node_id");
-            let subnets = DataColumnSubnetId::compute_custody_subnets::<E>(
-                node_id.raw(),
-                spec.custody_requirement,
-                spec,
-            )
-            .expect("should compute custody subnets")
-            .collect();
+            let subnets = compute_subnets_for_node(node_id.raw(), spec.custody_requirement, spec)
+                .expect("should compute custody subnets");
             peer_info.set_custody_subnets(subnets);
         }
 
@@ -1305,7 +1301,7 @@ impl BannedPeersCount {
     pub fn ip_is_banned(&self, ip: &IpAddr) -> bool {
         self.banned_peers_per_ip
             .get(ip)
-            .map_or(false, |count| *count > BANNED_PEERS_PER_IP_THRESHOLD)
+            .is_some_and(|count| *count > BANNED_PEERS_PER_IP_THRESHOLD)
     }
 }
 
diff --git a/beacon_node/lighthouse_network/src/peer_manager/peerdb/peer_info.rs b/beacon_node/lighthouse_network/src/peer_manager/peerdb/peer_info.rs
index ee8c27f474..2e8f462565 100644
--- a/beacon_node/lighthouse_network/src/peer_manager/peerdb/peer_info.rs
+++ b/beacon_node/lighthouse_network/src/peer_manager/peerdb/peer_info.rs
@@ -89,7 +89,7 @@ impl<E: EthSpec> PeerInfo<E> {
     }
 
     /// Returns if the peer is subscribed to a given `Subnet` from the metadata attnets/syncnets field.
-    /// Also returns true if the peer is assigned to custody a given data column `Subnet` computed from the metadata `custody_column_count` field or ENR `csc` field.
+    /// Also returns true if the peer is assigned to custody a given data column `Subnet` computed from the metadata `custody_group_count` field or ENR `cgc` field.
     pub fn on_subnet_metadata(&self, subnet: &Subnet) -> bool {
         if let Some(meta_data) = &self.meta_data {
             match subnet {
@@ -99,9 +99,11 @@ impl<E: EthSpec> PeerInfo<E> {
                 Subnet::SyncCommittee(id) => {
                     return meta_data
                         .syncnets()
-                        .map_or(false, |s| s.get(**id as usize).unwrap_or(false))
+                        .is_ok_and(|s| s.get(**id as usize).unwrap_or(false))
+                }
+                Subnet::DataColumn(subnet_id) => {
+                    return self.is_assigned_to_custody_subnet(subnet_id)
                 }
-                Subnet::DataColumn(column) => return self.custody_subnets.contains(column),
             }
         }
         false
@@ -122,6 +124,24 @@ impl<E: EthSpec> PeerInfo<E> {
         self.connection_direction.as_ref()
     }
 
+    /// Returns true if this is an incoming ipv4 connection.
+    pub fn is_incoming_ipv4_connection(&self) -> bool {
+        self.seen_multiaddrs.iter().any(|multiaddr| {
+            multiaddr
+                .iter()
+                .any(|protocol| matches!(protocol, libp2p::core::multiaddr::Protocol::Ip4(_)))
+        })
+    }
+
+    /// Returns true if this is an incoming ipv6 connection.
+    pub fn is_incoming_ipv6_connection(&self) -> bool {
+        self.seen_multiaddrs.iter().any(|multiaddr| {
+            multiaddr
+                .iter()
+                .any(|protocol| matches!(protocol, libp2p::core::multiaddr::Protocol::Ip6(_)))
+        })
+    }
+
     /// Returns the sync status of the peer.
     pub fn sync_status(&self) -> &SyncStatus {
         &self.sync_status
@@ -264,7 +284,7 @@ impl<E: EthSpec> PeerInfo<E> {
 
     /// Reports if this peer has some future validator duty in which case it is valuable to keep it.
     pub fn has_future_duty(&self) -> bool {
-        self.min_ttl.map_or(false, |i| i >= Instant::now())
+        self.min_ttl.is_some_and(|i| i >= Instant::now())
     }
 
     /// Returns score of the peer.
diff --git a/beacon_node/lighthouse_network/src/rpc/codec.rs b/beacon_node/lighthouse_network/src/rpc/codec.rs
index 5d86936d41..2bf35b0e35 100644
--- a/beacon_node/lighthouse_network/src/rpc/codec.rs
+++ b/beacon_node/lighthouse_network/src/rpc/codec.rs
@@ -20,7 +20,7 @@ use types::{
     LightClientBootstrap, LightClientFinalityUpdate, LightClientOptimisticUpdate,
     LightClientUpdate, RuntimeVariableList, SignedBeaconBlock, SignedBeaconBlockAltair,
     SignedBeaconBlockBase, SignedBeaconBlockBellatrix, SignedBeaconBlockCapella,
-    SignedBeaconBlockDeneb, SignedBeaconBlockElectra,
+    SignedBeaconBlockDeneb, SignedBeaconBlockElectra, SignedBeaconBlockFulu,
 };
 use unsigned_varint::codec::Uvi;
 
@@ -186,6 +186,7 @@ impl<E: EthSpec> Decoder for SSZSnappyInboundCodec<E> {
                 handle_rpc_request(
                     self.protocol.versioned_protocol,
                     &decoded_buffer,
+                    self.fork_context.current_fork(),
                     &self.fork_context.spec,
                 )
             }
@@ -458,6 +459,9 @@ fn context_bytes<E: EthSpec>(
                     return match **ref_box_block {
                         // NOTE: If you are adding another fork type here, be sure to modify the
                         //       `fork_context.to_context_bytes()` function to support it as well!
+                        SignedBeaconBlock::Fulu { .. } => {
+                            fork_context.to_context_bytes(ForkName::Fulu)
+                        }
                         SignedBeaconBlock::Electra { .. } => {
                             fork_context.to_context_bytes(ForkName::Electra)
                         }
@@ -481,17 +485,9 @@ fn context_bytes<E: EthSpec>(
                 RpcSuccessResponse::BlobsByRange(_) | RpcSuccessResponse::BlobsByRoot(_) => {
                     return fork_context.to_context_bytes(ForkName::Deneb);
                 }
-                RpcSuccessResponse::DataColumnsByRoot(d)
-                | RpcSuccessResponse::DataColumnsByRange(d) => {
-                    // TODO(das): Remove deneb fork after `peerdas-devnet-2`.
-                    return if matches!(
-                        fork_context.spec.fork_name_at_slot::<E>(d.slot()),
-                        ForkName::Deneb
-                    ) {
-                        fork_context.to_context_bytes(ForkName::Deneb)
-                    } else {
-                        fork_context.to_context_bytes(ForkName::Electra)
-                    };
+                RpcSuccessResponse::DataColumnsByRoot(_)
+                | RpcSuccessResponse::DataColumnsByRange(_) => {
+                    return fork_context.to_context_bytes(ForkName::Fulu);
                 }
                 RpcSuccessResponse::LightClientBootstrap(lc_bootstrap) => {
                     return lc_bootstrap
@@ -552,6 +548,7 @@ fn handle_length(
 fn handle_rpc_request<E: EthSpec>(
     versioned_protocol: SupportedProtocol,
     decoded_buffer: &[u8],
+    current_fork: ForkName,
     spec: &ChainSpec,
 ) -> Result<Option<RequestType<E>>, RPCError> {
     match versioned_protocol {
@@ -571,7 +568,7 @@ fn handle_rpc_request<E: EthSpec>(
             BlocksByRootRequest::V2(BlocksByRootRequestV2 {
                 block_roots: RuntimeVariableList::from_ssz_bytes(
                     decoded_buffer,
-                    spec.max_request_blocks as usize,
+                    spec.max_request_blocks(current_fork),
                 )?,
             }),
         ))),
@@ -579,7 +576,7 @@ fn handle_rpc_request<E: EthSpec>(
             BlocksByRootRequest::V1(BlocksByRootRequestV1 {
                 block_roots: RuntimeVariableList::from_ssz_bytes(
                     decoded_buffer,
-                    spec.max_request_blocks as usize,
+                    spec.max_request_blocks(current_fork),
                 )?,
             }),
         ))),
@@ -590,7 +587,7 @@ fn handle_rpc_request<E: EthSpec>(
             Ok(Some(RequestType::BlobsByRoot(BlobsByRootRequest {
                 blob_ids: RuntimeVariableList::from_ssz_bytes(
                     decoded_buffer,
-                    spec.max_request_blob_sidecars as usize,
+                    spec.max_request_blob_sidecars(current_fork),
                 )?,
             })))
         }
@@ -682,18 +679,18 @@ fn handle_rpc_response<E: EthSpec>(
             SignedBeaconBlock::Base(SignedBeaconBlockBase::from_ssz_bytes(decoded_buffer)?),
         )))),
         SupportedProtocol::BlobsByRangeV1 => match fork_name {
-            Some(ForkName::Deneb) | Some(ForkName::Electra) => {
-                Ok(Some(RpcSuccessResponse::BlobsByRange(Arc::new(
-                    BlobSidecar::from_ssz_bytes(decoded_buffer)?,
-                ))))
+            Some(fork_name) => {
+                if fork_name.deneb_enabled() {
+                    Ok(Some(RpcSuccessResponse::BlobsByRange(Arc::new(
+                        BlobSidecar::from_ssz_bytes(decoded_buffer)?,
+                    ))))
+                } else {
+                    Err(RPCError::ErrorResponse(
+                        RpcErrorResponse::InvalidRequest,
+                        "Invalid fork name for blobs by range".to_string(),
+                    ))
+                }
             }
-            Some(ForkName::Base)
-            | Some(ForkName::Altair)
-            | Some(ForkName::Bellatrix)
-            | Some(ForkName::Capella) => Err(RPCError::ErrorResponse(
-                RpcErrorResponse::InvalidRequest,
-                "Invalid fork name for blobs by range".to_string(),
-            )),
             None => Err(RPCError::ErrorResponse(
                 RpcErrorResponse::InvalidRequest,
                 format!(
@@ -703,18 +700,18 @@ fn handle_rpc_response<E: EthSpec>(
             )),
         },
         SupportedProtocol::BlobsByRootV1 => match fork_name {
-            Some(ForkName::Deneb) | Some(ForkName::Electra) => {
-                Ok(Some(RpcSuccessResponse::BlobsByRoot(Arc::new(
-                    BlobSidecar::from_ssz_bytes(decoded_buffer)?,
-                ))))
+            Some(fork_name) => {
+                if fork_name.deneb_enabled() {
+                    Ok(Some(RpcSuccessResponse::BlobsByRoot(Arc::new(
+                        BlobSidecar::from_ssz_bytes(decoded_buffer)?,
+                    ))))
+                } else {
+                    Err(RPCError::ErrorResponse(
+                        RpcErrorResponse::InvalidRequest,
+                        "Invalid fork name for blobs by root".to_string(),
+                    ))
+                }
             }
-            Some(ForkName::Base)
-            | Some(ForkName::Altair)
-            | Some(ForkName::Bellatrix)
-            | Some(ForkName::Capella) => Err(RPCError::ErrorResponse(
-                RpcErrorResponse::InvalidRequest,
-                "Invalid fork name for blobs by root".to_string(),
-            )),
             None => Err(RPCError::ErrorResponse(
                 RpcErrorResponse::InvalidRequest,
                 format!(
@@ -725,10 +722,7 @@ fn handle_rpc_response<E: EthSpec>(
         },
         SupportedProtocol::DataColumnsByRootV1 => match fork_name {
             Some(fork_name) => {
-                // TODO(das): PeerDAS is currently supported for both deneb and electra. This check
-                // does not advertise the topic on deneb, simply allows it to decode it. Advertise
-                // logic is in `SupportedTopic::currently_supported`.
-                if fork_name.deneb_enabled() {
+                if fork_name.fulu_enabled() {
                     Ok(Some(RpcSuccessResponse::DataColumnsByRoot(Arc::new(
                         DataColumnSidecar::from_ssz_bytes(decoded_buffer)?,
                     ))))
@@ -749,7 +743,7 @@ fn handle_rpc_response<E: EthSpec>(
         },
         SupportedProtocol::DataColumnsByRangeV1 => match fork_name {
             Some(fork_name) => {
-                if fork_name.deneb_enabled() {
+                if fork_name.fulu_enabled() {
                     Ok(Some(RpcSuccessResponse::DataColumnsByRange(Arc::new(
                         DataColumnSidecar::from_ssz_bytes(decoded_buffer)?,
                     ))))
@@ -864,6 +858,9 @@ fn handle_rpc_response<E: EthSpec>(
                     decoded_buffer,
                 )?),
             )))),
+            Some(ForkName::Fulu) => Ok(Some(RpcSuccessResponse::BlocksByRange(Arc::new(
+                SignedBeaconBlock::Fulu(SignedBeaconBlockFulu::from_ssz_bytes(decoded_buffer)?),
+            )))),
             None => Err(RPCError::ErrorResponse(
                 RpcErrorResponse::InvalidRequest,
                 format!(
@@ -897,6 +894,9 @@ fn handle_rpc_response<E: EthSpec>(
                     decoded_buffer,
                 )?),
             )))),
+            Some(ForkName::Fulu) => Ok(Some(RpcSuccessResponse::BlocksByRoot(Arc::new(
+                SignedBeaconBlock::Fulu(SignedBeaconBlockFulu::from_ssz_bytes(decoded_buffer)?),
+            )))),
             None => Err(RPCError::ErrorResponse(
                 RpcErrorResponse::InvalidRequest,
                 format!(
@@ -934,9 +934,10 @@ mod tests {
     use crate::rpc::protocol::*;
     use crate::types::{EnrAttestationBitfield, EnrSyncCommitteeBitfield};
     use types::{
-        blob_sidecar::BlobIdentifier, BeaconBlock, BeaconBlockAltair, BeaconBlockBase,
-        BeaconBlockBellatrix, DataColumnIdentifier, EmptyBlock, Epoch, FixedBytesExtended,
-        FullPayload, Signature, Slot,
+        blob_sidecar::BlobIdentifier, data_column_sidecar::Cell, BeaconBlock, BeaconBlockAltair,
+        BeaconBlockBase, BeaconBlockBellatrix, BeaconBlockHeader, DataColumnIdentifier, EmptyBlock,
+        Epoch, FixedBytesExtended, FullPayload, KzgCommitment, KzgProof, Signature,
+        SignedBeaconBlockHeader, Slot,
     };
 
     type Spec = types::MainnetEthSpec;
@@ -948,12 +949,14 @@ mod tests {
         let capella_fork_epoch = Epoch::new(3);
         let deneb_fork_epoch = Epoch::new(4);
         let electra_fork_epoch = Epoch::new(5);
+        let fulu_fork_epoch = Epoch::new(6);
 
         chain_spec.altair_fork_epoch = Some(altair_fork_epoch);
         chain_spec.bellatrix_fork_epoch = Some(bellatrix_fork_epoch);
         chain_spec.capella_fork_epoch = Some(capella_fork_epoch);
         chain_spec.deneb_fork_epoch = Some(deneb_fork_epoch);
         chain_spec.electra_fork_epoch = Some(electra_fork_epoch);
+        chain_spec.fulu_fork_epoch = Some(fulu_fork_epoch);
 
         let current_slot = match fork_name {
             ForkName::Base => Slot::new(0),
@@ -962,6 +965,7 @@ mod tests {
             ForkName::Capella => capella_fork_epoch.start_slot(Spec::slots_per_epoch()),
             ForkName::Deneb => deneb_fork_epoch.start_slot(Spec::slots_per_epoch()),
             ForkName::Electra => electra_fork_epoch.start_slot(Spec::slots_per_epoch()),
+            ForkName::Fulu => fulu_fork_epoch.start_slot(Spec::slots_per_epoch()),
         };
         ForkContext::new::<Spec>(current_slot, Hash256::zero(), &chain_spec)
     }
@@ -984,7 +988,17 @@ mod tests {
     }
 
     fn empty_data_column_sidecar() -> Arc<DataColumnSidecar<Spec>> {
-        Arc::new(DataColumnSidecar::empty())
+        Arc::new(DataColumnSidecar {
+            index: 0,
+            column: VariableList::new(vec![Cell::<Spec>::default()]).unwrap(),
+            kzg_commitments: VariableList::new(vec![KzgCommitment::empty_for_testing()]).unwrap(),
+            kzg_proofs: VariableList::new(vec![KzgProof::empty()]).unwrap(),
+            signed_block_header: SignedBeaconBlockHeader {
+                message: BeaconBlockHeader::empty(),
+                signature: Signature::empty(),
+            },
+            kzg_commitments_inclusion_proof: Default::default(),
+        })
     }
 
     /// Bellatrix block with length < max_rpc_size.
@@ -1069,21 +1083,21 @@ mod tests {
         }
     }
 
-    fn bbroot_request_v1(spec: &ChainSpec) -> BlocksByRootRequest {
-        BlocksByRootRequest::new_v1(vec![Hash256::zero()], spec)
+    fn bbroot_request_v1(fork_name: ForkName) -> BlocksByRootRequest {
+        BlocksByRootRequest::new_v1(vec![Hash256::zero()], &fork_context(fork_name))
     }
 
-    fn bbroot_request_v2(spec: &ChainSpec) -> BlocksByRootRequest {
-        BlocksByRootRequest::new(vec![Hash256::zero()], spec)
+    fn bbroot_request_v2(fork_name: ForkName) -> BlocksByRootRequest {
+        BlocksByRootRequest::new(vec![Hash256::zero()], &fork_context(fork_name))
     }
 
-    fn blbroot_request(spec: &ChainSpec) -> BlobsByRootRequest {
+    fn blbroot_request(fork_name: ForkName) -> BlobsByRootRequest {
         BlobsByRootRequest::new(
             vec![BlobIdentifier {
                 block_root: Hash256::zero(),
                 index: 0,
             }],
-            spec,
+            &fork_context(fork_name),
         )
     }
 
@@ -1111,7 +1125,7 @@ mod tests {
             seq_number: 1,
             attnets: EnrAttestationBitfield::<Spec>::default(),
             syncnets: EnrSyncCommitteeBitfield::<Spec>::default(),
-            custody_subnet_count: 1,
+            custody_group_count: 1,
         })
     }
 
@@ -1396,6 +1410,16 @@ mod tests {
             Ok(Some(RpcSuccessResponse::BlobsByRange(empty_blob_sidecar()))),
         );
 
+        assert_eq!(
+            encode_then_decode_response(
+                SupportedProtocol::BlobsByRangeV1,
+                RpcResponse::Success(RpcSuccessResponse::BlobsByRange(empty_blob_sidecar())),
+                ForkName::Fulu,
+                &chain_spec
+            ),
+            Ok(Some(RpcSuccessResponse::BlobsByRange(empty_blob_sidecar()))),
+        );
+
         assert_eq!(
             encode_then_decode_response(
                 SupportedProtocol::BlobsByRootV1,
@@ -1416,6 +1440,16 @@ mod tests {
             Ok(Some(RpcSuccessResponse::BlobsByRoot(empty_blob_sidecar()))),
         );
 
+        assert_eq!(
+            encode_then_decode_response(
+                SupportedProtocol::BlobsByRootV1,
+                RpcResponse::Success(RpcSuccessResponse::BlobsByRoot(empty_blob_sidecar())),
+                ForkName::Fulu,
+                &chain_spec
+            ),
+            Ok(Some(RpcSuccessResponse::BlobsByRoot(empty_blob_sidecar()))),
+        );
+
         assert_eq!(
             encode_then_decode_response(
                 SupportedProtocol::DataColumnsByRangeV1,
@@ -1444,6 +1478,20 @@ mod tests {
             ))),
         );
 
+        assert_eq!(
+            encode_then_decode_response(
+                SupportedProtocol::DataColumnsByRangeV1,
+                RpcResponse::Success(RpcSuccessResponse::DataColumnsByRange(
+                    empty_data_column_sidecar()
+                )),
+                ForkName::Fulu,
+                &chain_spec
+            ),
+            Ok(Some(RpcSuccessResponse::DataColumnsByRange(
+                empty_data_column_sidecar()
+            ))),
+        );
+
         assert_eq!(
             encode_then_decode_response(
                 SupportedProtocol::DataColumnsByRootV1,
@@ -1471,6 +1519,20 @@ mod tests {
                 empty_data_column_sidecar()
             ))),
         );
+
+        assert_eq!(
+            encode_then_decode_response(
+                SupportedProtocol::DataColumnsByRootV1,
+                RpcResponse::Success(RpcSuccessResponse::DataColumnsByRoot(
+                    empty_data_column_sidecar()
+                )),
+                ForkName::Fulu,
+                &chain_spec
+            ),
+            Ok(Some(RpcSuccessResponse::DataColumnsByRoot(
+                empty_data_column_sidecar()
+            ))),
+        );
     }
 
     // Test RPCResponse encoding/decoding for V1 messages
@@ -1833,7 +1895,8 @@ mod tests {
 
     #[test]
     fn test_encode_then_decode_request() {
-        let chain_spec = Spec::default_spec();
+        let fork_context = fork_context(ForkName::Electra);
+        let chain_spec = fork_context.spec.clone();
 
         let requests: &[RequestType<Spec>] = &[
             RequestType::Ping(ping_message()),
@@ -1841,21 +1904,33 @@ mod tests {
             RequestType::Goodbye(GoodbyeReason::Fault),
             RequestType::BlocksByRange(bbrange_request_v1()),
             RequestType::BlocksByRange(bbrange_request_v2()),
-            RequestType::BlocksByRoot(bbroot_request_v1(&chain_spec)),
-            RequestType::BlocksByRoot(bbroot_request_v2(&chain_spec)),
             RequestType::MetaData(MetadataRequest::new_v1()),
             RequestType::BlobsByRange(blbrange_request()),
-            RequestType::BlobsByRoot(blbroot_request(&chain_spec)),
             RequestType::DataColumnsByRange(dcbrange_request()),
             RequestType::DataColumnsByRoot(dcbroot_request(&chain_spec)),
             RequestType::MetaData(MetadataRequest::new_v2()),
         ];
-
         for req in requests.iter() {
             for fork_name in ForkName::list_all() {
                 encode_then_decode_request(req.clone(), fork_name, &chain_spec);
             }
         }
+
+        // Request types that have different length limits depending on the fork
+        // Handled separately to have consistent `ForkName` across request and responses
+        let fork_dependent_requests = |fork_name| {
+            [
+                RequestType::BlobsByRoot(blbroot_request(fork_name)),
+                RequestType::BlocksByRoot(bbroot_request_v1(fork_name)),
+                RequestType::BlocksByRoot(bbroot_request_v2(fork_name)),
+            ]
+        };
+        for fork_name in ForkName::list_all() {
+            let requests = fork_dependent_requests(fork_name);
+            for req in requests {
+                encode_then_decode_request(req.clone(), fork_name, &chain_spec);
+            }
+        }
     }
 
     /// Test a malicious snappy encoding for a V1 `Status` message where the attacker
diff --git a/beacon_node/lighthouse_network/src/rpc/config.rs b/beacon_node/lighthouse_network/src/rpc/config.rs
index 7b3a59eac7..75d49e9cb5 100644
--- a/beacon_node/lighthouse_network/src/rpc/config.rs
+++ b/beacon_node/lighthouse_network/src/rpc/config.rs
@@ -110,8 +110,8 @@ impl RateLimiterConfig {
     pub const DEFAULT_BLOCKS_BY_RANGE_QUOTA: Quota = Quota::n_every(128, 10);
     pub const DEFAULT_BLOCKS_BY_ROOT_QUOTA: Quota = Quota::n_every(128, 10);
     // `DEFAULT_BLOCKS_BY_RANGE_QUOTA` * (target + 1) to account for high usage
-    pub const DEFAULT_BLOBS_BY_RANGE_QUOTA: Quota = Quota::n_every(512, 10);
-    pub const DEFAULT_BLOBS_BY_ROOT_QUOTA: Quota = Quota::n_every(512, 10);
+    pub const DEFAULT_BLOBS_BY_RANGE_QUOTA: Quota = Quota::n_every(896, 10);
+    pub const DEFAULT_BLOBS_BY_ROOT_QUOTA: Quota = Quota::n_every(896, 10);
     // 320 blocks worth of columns for regular node, or 40 blocks for supernode.
     // Range sync load balances when requesting blocks, and each batch is 32 blocks.
     pub const DEFAULT_DATA_COLUMNS_BY_RANGE_QUOTA: Quota = Quota::n_every(5120, 10);
diff --git a/beacon_node/lighthouse_network/src/rpc/handler.rs b/beacon_node/lighthouse_network/src/rpc/handler.rs
index 0a0a6ca754..03203fcade 100644
--- a/beacon_node/lighthouse_network/src/rpc/handler.rs
+++ b/beacon_node/lighthouse_network/src/rpc/handler.rs
@@ -353,6 +353,7 @@ where
         !matches!(self.state, HandlerState::Deactivated)
     }
 
+    #[allow(deprecated)]
     fn poll(
         &mut self,
         cx: &mut Context<'_>,
@@ -814,6 +815,7 @@ where
         Poll::Pending
     }
 
+    #[allow(deprecated)]
     fn on_connection_event(
         &mut self,
         event: ConnectionEvent<
@@ -855,7 +857,47 @@ where
         }
 
         let (req, substream) = substream;
-        let max_responses = req.max_responses();
+        let current_fork = self.fork_context.current_fork();
+        let spec = &self.fork_context.spec;
+
+        match &req {
+            RequestType::BlocksByRange(request) => {
+                let max_allowed = spec.max_request_blocks(current_fork) as u64;
+                if *request.count() > max_allowed {
+                    self.events_out.push(HandlerEvent::Err(HandlerErr::Inbound {
+                        id: self.current_inbound_substream_id,
+                        proto: Protocol::BlocksByRange,
+                        error: RPCError::InvalidData(format!(
+                            "requested exceeded limit. allowed: {}, requested: {}",
+                            max_allowed,
+                            request.count()
+                        )),
+                    }));
+                    return self.shutdown(None);
+                }
+            }
+            RequestType::BlobsByRange(request) => {
+                let max_requested_blobs = request
+                    .count
+                    .saturating_mul(spec.max_blobs_per_block_by_fork(current_fork));
+                let max_allowed = spec.max_request_blob_sidecars(current_fork) as u64;
+                if max_requested_blobs > max_allowed {
+                    self.events_out.push(HandlerEvent::Err(HandlerErr::Inbound {
+                        id: self.current_inbound_substream_id,
+                        proto: Protocol::BlobsByRange,
+                        error: RPCError::InvalidData(format!(
+                            "requested exceeded limit. allowed: {}, requested: {}",
+                            max_allowed, max_requested_blobs
+                        )),
+                    }));
+                    return self.shutdown(None);
+                }
+            }
+            _ => {}
+        };
+
+        let max_responses =
+            req.max_responses(self.fork_context.current_fork(), &self.fork_context.spec);
 
         // store requests that expect responses
         if max_responses > 0 {
@@ -924,7 +966,8 @@ where
         }
 
         // add the stream to substreams if we expect a response, otherwise drop the stream.
-        let max_responses = request.max_responses();
+        let max_responses =
+            request.max_responses(self.fork_context.current_fork(), &self.fork_context.spec);
         if max_responses > 0 {
             let max_remaining_chunks = if request.expect_exactly_one_response() {
                 // Currently enforced only for multiple responses
diff --git a/beacon_node/lighthouse_network/src/rpc/methods.rs b/beacon_node/lighthouse_network/src/rpc/methods.rs
index bb8bfb0e20..ad6bea455e 100644
--- a/beacon_node/lighthouse_network/src/rpc/methods.rs
+++ b/beacon_node/lighthouse_network/src/rpc/methods.rs
@@ -20,6 +20,7 @@ use types::{
     Epoch, EthSpec, Hash256, LightClientBootstrap, LightClientFinalityUpdate,
     LightClientOptimisticUpdate, LightClientUpdate, RuntimeVariableList, SignedBeaconBlock, Slot,
 };
+use types::{ForkContext, ForkName};
 
 /// Maximum length of error message.
 pub type MaxErrorLen = U256;
@@ -137,7 +138,7 @@ pub struct MetaData<E: EthSpec> {
     #[superstruct(only(V2, V3))]
     pub syncnets: EnrSyncCommitteeBitfield<E>,
     #[superstruct(only(V3))]
-    pub custody_subnet_count: u64,
+    pub custody_group_count: u64,
 }
 
 impl<E: EthSpec> MetaData<E> {
@@ -180,13 +181,13 @@ impl<E: EthSpec> MetaData<E> {
                 seq_number: metadata.seq_number,
                 attnets: metadata.attnets.clone(),
                 syncnets: Default::default(),
-                custody_subnet_count: spec.custody_requirement,
+                custody_group_count: spec.custody_requirement,
             }),
             MetaData::V2(metadata) => MetaData::V3(MetaDataV3 {
                 seq_number: metadata.seq_number,
                 attnets: metadata.attnets.clone(),
                 syncnets: metadata.syncnets.clone(),
-                custody_subnet_count: spec.custody_requirement,
+                custody_group_count: spec.custody_requirement,
             }),
             md @ MetaData::V3(_) => md.clone(),
         }
@@ -327,8 +328,9 @@ pub struct BlobsByRangeRequest {
 }
 
 impl BlobsByRangeRequest {
-    pub fn max_blobs_requested<E: EthSpec>(&self) -> u64 {
-        self.count.saturating_mul(E::max_blobs_per_block() as u64)
+    pub fn max_blobs_requested(&self, current_fork: ForkName, spec: &ChainSpec) -> u64 {
+        let max_blobs_per_block = spec.max_blobs_per_block_by_fork(current_fork);
+        self.count.saturating_mul(max_blobs_per_block)
     }
 }
 
@@ -362,7 +364,7 @@ impl DataColumnsByRangeRequest {
         DataColumnsByRangeRequest {
             start_slot: 0,
             count: 0,
-            columns: vec![0; spec.number_of_columns],
+            columns: vec![0; spec.number_of_columns as usize],
         }
         .as_ssz_bytes()
         .len()
@@ -418,15 +420,19 @@ pub struct BlocksByRootRequest {
 }
 
 impl BlocksByRootRequest {
-    pub fn new(block_roots: Vec<Hash256>, spec: &ChainSpec) -> Self {
-        let block_roots =
-            RuntimeVariableList::from_vec(block_roots, spec.max_request_blocks as usize);
+    pub fn new(block_roots: Vec<Hash256>, fork_context: &ForkContext) -> Self {
+        let max_request_blocks = fork_context
+            .spec
+            .max_request_blocks(fork_context.current_fork());
+        let block_roots = RuntimeVariableList::from_vec(block_roots, max_request_blocks);
         Self::V2(BlocksByRootRequestV2 { block_roots })
     }
 
-    pub fn new_v1(block_roots: Vec<Hash256>, spec: &ChainSpec) -> Self {
-        let block_roots =
-            RuntimeVariableList::from_vec(block_roots, spec.max_request_blocks as usize);
+    pub fn new_v1(block_roots: Vec<Hash256>, fork_context: &ForkContext) -> Self {
+        let max_request_blocks = fork_context
+            .spec
+            .max_request_blocks(fork_context.current_fork());
+        let block_roots = RuntimeVariableList::from_vec(block_roots, max_request_blocks);
         Self::V1(BlocksByRootRequestV1 { block_roots })
     }
 }
@@ -439,9 +445,11 @@ pub struct BlobsByRootRequest {
 }
 
 impl BlobsByRootRequest {
-    pub fn new(blob_ids: Vec<BlobIdentifier>, spec: &ChainSpec) -> Self {
-        let blob_ids =
-            RuntimeVariableList::from_vec(blob_ids, spec.max_request_blob_sidecars as usize);
+    pub fn new(blob_ids: Vec<BlobIdentifier>, fork_context: &ForkContext) -> Self {
+        let max_request_blob_sidecars = fork_context
+            .spec
+            .max_request_blob_sidecars(fork_context.current_fork());
+        let blob_ids = RuntimeVariableList::from_vec(blob_ids, max_request_blob_sidecars);
         Self { blob_ids }
     }
 }
diff --git a/beacon_node/lighthouse_network/src/rpc/mod.rs b/beacon_node/lighthouse_network/src/rpc/mod.rs
index 7d091da766..03f1395b8b 100644
--- a/beacon_node/lighthouse_network/src/rpc/mod.rs
+++ b/beacon_node/lighthouse_network/src/rpc/mod.rs
@@ -181,12 +181,13 @@ impl<Id: ReqId, E: EthSpec> RPC<Id, E> {
 
         let inbound_limiter = inbound_rate_limiter_config.map(|config| {
             debug!(log, "Using inbound rate limiting params"; "config" => ?config);
-            RateLimiter::new_with_config(config.0)
+            RateLimiter::new_with_config(config.0, fork_context.clone())
                 .expect("Inbound limiter configuration parameters are valid")
         });
 
         let self_limiter = outbound_rate_limiter_config.map(|config| {
-            SelfRateLimiter::new(config, log.clone()).expect("Configuration parameters are valid")
+            SelfRateLimiter::new(config, fork_context.clone(), log.clone())
+                .expect("Configuration parameters are valid")
         });
 
         RPC {
diff --git a/beacon_node/lighthouse_network/src/rpc/protocol.rs b/beacon_node/lighthouse_network/src/rpc/protocol.rs
index 57c2795b04..eac7d67490 100644
--- a/beacon_node/lighthouse_network/src/rpc/protocol.rs
+++ b/beacon_node/lighthouse_network/src/rpc/protocol.rs
@@ -17,12 +17,11 @@ use tokio_util::{
     compat::{Compat, FuturesAsyncReadCompatExt},
 };
 use types::{
-    BeaconBlock, BeaconBlockAltair, BeaconBlockBase, BeaconBlockCapella, BeaconBlockElectra,
-    BlobSidecar, ChainSpec, DataColumnSidecar, EmptyBlock, EthSpec, EthSpecId, ForkContext,
-    ForkName, LightClientBootstrap, LightClientBootstrapAltair, LightClientFinalityUpdate,
-    LightClientFinalityUpdateAltair, LightClientOptimisticUpdate,
-    LightClientOptimisticUpdateAltair, LightClientUpdate, MainnetEthSpec, MinimalEthSpec,
-    Signature, SignedBeaconBlock,
+    BeaconBlock, BeaconBlockAltair, BeaconBlockBase, BlobSidecar, ChainSpec, DataColumnSidecar,
+    EmptyBlock, EthSpec, EthSpecId, ForkContext, ForkName, LightClientBootstrap,
+    LightClientBootstrapAltair, LightClientFinalityUpdate, LightClientFinalityUpdateAltair,
+    LightClientOptimisticUpdate, LightClientOptimisticUpdateAltair, LightClientUpdate,
+    MainnetEthSpec, MinimalEthSpec, Signature, SignedBeaconBlock,
 };
 
 // Note: Hardcoding the `EthSpec` type for `SignedBeaconBlock` as min/max values is
@@ -55,24 +54,6 @@ pub static SIGNED_BEACON_BLOCK_ALTAIR_MAX: LazyLock<usize> = LazyLock::new(|| {
     .len()
 });
 
-pub static SIGNED_BEACON_BLOCK_CAPELLA_MAX_WITHOUT_PAYLOAD: LazyLock<usize> = LazyLock::new(|| {
-    SignedBeaconBlock::<MainnetEthSpec>::from_block(
-        BeaconBlock::Capella(BeaconBlockCapella::full(&MainnetEthSpec::default_spec())),
-        Signature::empty(),
-    )
-    .as_ssz_bytes()
-    .len()
-});
-
-pub static SIGNED_BEACON_BLOCK_ELECTRA_MAX_WITHOUT_PAYLOAD: LazyLock<usize> = LazyLock::new(|| {
-    SignedBeaconBlock::<MainnetEthSpec>::from_block(
-        BeaconBlock::Electra(BeaconBlockElectra::full(&MainnetEthSpec::default_spec())),
-        Signature::empty(),
-    )
-    .as_ssz_bytes()
-    .len()
-});
-
 /// The `BeaconBlockBellatrix` block has an `ExecutionPayload` field which has a max size ~16 GiB for future proofing.
 /// We calculate the value from its fields instead of constructing the block and checking the length.
 /// Note: This is only the theoretical upper bound. We further bound the max size we receive over the network
@@ -83,42 +64,12 @@ pub static SIGNED_BEACON_BLOCK_BELLATRIX_MAX: LazyLock<usize> =
     + types::ExecutionPayload::<MainnetEthSpec>::max_execution_payload_bellatrix_size() // adding max size of execution payload (~16gb)
     + ssz::BYTES_PER_LENGTH_OFFSET); // Adding the additional ssz offset for the `ExecutionPayload` field
 
-pub static SIGNED_BEACON_BLOCK_CAPELLA_MAX: LazyLock<usize> = LazyLock::new(|| {
-    *SIGNED_BEACON_BLOCK_CAPELLA_MAX_WITHOUT_PAYLOAD
-    + types::ExecutionPayload::<MainnetEthSpec>::max_execution_payload_capella_size() // adding max size of execution payload (~16gb)
-    + ssz::BYTES_PER_LENGTH_OFFSET
-}); // Adding the additional ssz offset for the `ExecutionPayload` field
-
-pub static SIGNED_BEACON_BLOCK_DENEB_MAX: LazyLock<usize> = LazyLock::new(|| {
-    *SIGNED_BEACON_BLOCK_CAPELLA_MAX_WITHOUT_PAYLOAD
-    + types::ExecutionPayload::<MainnetEthSpec>::max_execution_payload_deneb_size() // adding max size of execution payload (~16gb)
-    + ssz::BYTES_PER_LENGTH_OFFSET // Adding the additional offsets for the `ExecutionPayload`
-    + (<types::KzgCommitment as Encode>::ssz_fixed_len() * <MainnetEthSpec>::max_blobs_per_block())
-    + ssz::BYTES_PER_LENGTH_OFFSET
-}); // Length offset for the blob commitments field.
-    //
-pub static SIGNED_BEACON_BLOCK_ELECTRA_MAX: LazyLock<usize> = LazyLock::new(|| {
-    *SIGNED_BEACON_BLOCK_ELECTRA_MAX_WITHOUT_PAYLOAD
-    + types::ExecutionPayload::<MainnetEthSpec>::max_execution_payload_electra_size() // adding max size of execution payload (~16gb)
-    + ssz::BYTES_PER_LENGTH_OFFSET // Adding the additional ssz offset for the `ExecutionPayload` field
-    + (<types::KzgCommitment as Encode>::ssz_fixed_len() * <MainnetEthSpec>::max_blobs_per_block())
-    + ssz::BYTES_PER_LENGTH_OFFSET
-}); // Length offset for the blob commitments field.
-
 pub static BLOB_SIDECAR_SIZE: LazyLock<usize> =
     LazyLock::new(BlobSidecar::<MainnetEthSpec>::max_size);
 
 pub static BLOB_SIDECAR_SIZE_MINIMAL: LazyLock<usize> =
     LazyLock::new(BlobSidecar::<MinimalEthSpec>::max_size);
 
-pub static DATA_COLUMNS_SIDECAR_MIN: LazyLock<usize> = LazyLock::new(|| {
-    DataColumnSidecar::<MainnetEthSpec>::empty()
-        .as_ssz_bytes()
-        .len()
-});
-pub static DATA_COLUMNS_SIDECAR_MAX: LazyLock<usize> =
-    LazyLock::new(DataColumnSidecar::<MainnetEthSpec>::max_size);
-
 pub static ERROR_TYPE_MIN: LazyLock<usize> = LazyLock::new(|| {
     VariableList::<u8, MaxErrorLen>::from(Vec::<u8>::new())
         .as_ssz_bytes()
@@ -193,22 +144,12 @@ pub fn rpc_block_limits_by_fork(current_fork: ForkName) -> RpcLimits {
             *SIGNED_BEACON_BLOCK_BASE_MIN, // Base block is smaller than altair blocks
             *SIGNED_BEACON_BLOCK_ALTAIR_MAX, // Altair block is larger than base blocks
         ),
-        ForkName::Bellatrix => RpcLimits::new(
+        // After the merge the max SSZ size of a block is absurdly big. The size is actually
+        // bound by other constants, so here we default to the bellatrix's max value
+        _ => RpcLimits::new(
             *SIGNED_BEACON_BLOCK_BASE_MIN, // Base block is smaller than altair and bellatrix blocks
             *SIGNED_BEACON_BLOCK_BELLATRIX_MAX, // Bellatrix block is larger than base and altair blocks
         ),
-        ForkName::Capella => RpcLimits::new(
-            *SIGNED_BEACON_BLOCK_BASE_MIN, // Base block is smaller than altair and bellatrix blocks
-            *SIGNED_BEACON_BLOCK_CAPELLA_MAX, // Capella block is larger than base, altair and merge blocks
-        ),
-        ForkName::Deneb => RpcLimits::new(
-            *SIGNED_BEACON_BLOCK_BASE_MIN, // Base block is smaller than altair and bellatrix blocks
-            *SIGNED_BEACON_BLOCK_DENEB_MAX, // Deneb block is larger than all prior fork blocks
-        ),
-        ForkName::Electra => RpcLimits::new(
-            *SIGNED_BEACON_BLOCK_BASE_MIN, // Base block is smaller than altair and bellatrix blocks
-            *SIGNED_BEACON_BLOCK_ELECTRA_MAX, // Electra block is larger than Deneb block
-        ),
     }
 }
 
@@ -226,7 +167,7 @@ fn rpc_light_client_updates_by_range_limits_by_fork(current_fork: ForkName) -> R
         ForkName::Deneb => {
             RpcLimits::new(altair_fixed_len, *LIGHT_CLIENT_UPDATES_BY_RANGE_DENEB_MAX)
         }
-        ForkName::Electra => {
+        ForkName::Electra | ForkName::Fulu => {
             RpcLimits::new(altair_fixed_len, *LIGHT_CLIENT_UPDATES_BY_RANGE_ELECTRA_MAX)
         }
     }
@@ -246,7 +187,7 @@ fn rpc_light_client_finality_update_limits_by_fork(current_fork: ForkName) -> Rp
         ForkName::Deneb => {
             RpcLimits::new(altair_fixed_len, *LIGHT_CLIENT_FINALITY_UPDATE_DENEB_MAX)
         }
-        ForkName::Electra => {
+        ForkName::Electra | ForkName::Fulu => {
             RpcLimits::new(altair_fixed_len, *LIGHT_CLIENT_FINALITY_UPDATE_ELECTRA_MAX)
         }
     }
@@ -267,7 +208,7 @@ fn rpc_light_client_optimistic_update_limits_by_fork(current_fork: ForkName) ->
         ForkName::Deneb => {
             RpcLimits::new(altair_fixed_len, *LIGHT_CLIENT_OPTIMISTIC_UPDATE_DENEB_MAX)
         }
-        ForkName::Electra => RpcLimits::new(
+        ForkName::Electra | ForkName::Fulu => RpcLimits::new(
             altair_fixed_len,
             *LIGHT_CLIENT_OPTIMISTIC_UPDATE_ELECTRA_MAX,
         ),
@@ -284,7 +225,9 @@ fn rpc_light_client_bootstrap_limits_by_fork(current_fork: ForkName) -> RpcLimit
         }
         ForkName::Capella => RpcLimits::new(altair_fixed_len, *LIGHT_CLIENT_BOOTSTRAP_CAPELLA_MAX),
         ForkName::Deneb => RpcLimits::new(altair_fixed_len, *LIGHT_CLIENT_BOOTSTRAP_DENEB_MAX),
-        ForkName::Electra => RpcLimits::new(altair_fixed_len, *LIGHT_CLIENT_BOOTSTRAP_ELECTRA_MAX),
+        ForkName::Electra | ForkName::Fulu => {
+            RpcLimits::new(altair_fixed_len, *LIGHT_CLIENT_BOOTSTRAP_ELECTRA_MAX)
+        }
     }
 }
 
@@ -611,8 +554,12 @@ impl ProtocolId {
             Protocol::BlocksByRoot => rpc_block_limits_by_fork(fork_context.current_fork()),
             Protocol::BlobsByRange => rpc_blob_limits::<E>(),
             Protocol::BlobsByRoot => rpc_blob_limits::<E>(),
-            Protocol::DataColumnsByRoot => rpc_data_column_limits(),
-            Protocol::DataColumnsByRange => rpc_data_column_limits(),
+            Protocol::DataColumnsByRoot => {
+                rpc_data_column_limits::<E>(fork_context.current_fork(), &fork_context.spec)
+            }
+            Protocol::DataColumnsByRange => {
+                rpc_data_column_limits::<E>(fork_context.current_fork(), &fork_context.spec)
+            }
             Protocol::Ping => RpcLimits::new(
                 <Ping as Encode>::ssz_fixed_len(),
                 <Ping as Encode>::ssz_fixed_len(),
@@ -692,8 +639,11 @@ pub fn rpc_blob_limits<E: EthSpec>() -> RpcLimits {
     }
 }
 
-pub fn rpc_data_column_limits() -> RpcLimits {
-    RpcLimits::new(*DATA_COLUMNS_SIDECAR_MIN, *DATA_COLUMNS_SIDECAR_MAX)
+pub fn rpc_data_column_limits<E: EthSpec>(fork_name: ForkName, spec: &ChainSpec) -> RpcLimits {
+    RpcLimits::new(
+        DataColumnSidecar::<E>::min_size(),
+        DataColumnSidecar::<E>::max_size(spec.max_blobs_per_block_by_fork(fork_name) as usize),
+    )
 }
 
 /* Inbound upgrade */
@@ -791,13 +741,13 @@ impl<E: EthSpec> RequestType<E> {
     /* These functions are used in the handler for stream management */
 
     /// Maximum number of responses expected for this request.
-    pub fn max_responses(&self) -> u64 {
+    pub fn max_responses(&self, current_fork: ForkName, spec: &ChainSpec) -> u64 {
         match self {
             RequestType::Status(_) => 1,
             RequestType::Goodbye(_) => 0,
             RequestType::BlocksByRange(req) => *req.count(),
             RequestType::BlocksByRoot(req) => req.block_roots().len() as u64,
-            RequestType::BlobsByRange(req) => req.max_blobs_requested::<E>(),
+            RequestType::BlobsByRange(req) => req.max_blobs_requested(current_fork, spec),
             RequestType::BlobsByRoot(req) => req.blob_ids.len() as u64,
             RequestType::DataColumnsByRoot(req) => req.data_column_ids.len() as u64,
             RequestType::DataColumnsByRange(req) => req.max_requested::<E>(),
diff --git a/beacon_node/lighthouse_network/src/rpc/rate_limiter.rs b/beacon_node/lighthouse_network/src/rpc/rate_limiter.rs
index ecbacc8c11..b9e82a5f1e 100644
--- a/beacon_node/lighthouse_network/src/rpc/rate_limiter.rs
+++ b/beacon_node/lighthouse_network/src/rpc/rate_limiter.rs
@@ -6,10 +6,11 @@ use serde::{Deserialize, Serialize};
 use std::future::Future;
 use std::hash::Hash;
 use std::pin::Pin;
+use std::sync::Arc;
 use std::task::{Context, Poll};
 use std::time::{Duration, Instant};
 use tokio::time::Interval;
-use types::EthSpec;
+use types::{ChainSpec, EthSpec, ForkContext, ForkName};
 
 /// Nanoseconds since a given time.
 // Maintained as u64 to reduce footprint
@@ -109,6 +110,7 @@ pub struct RPCRateLimiter {
     lc_finality_update_rl: Limiter<PeerId>,
     /// LightClientUpdatesByRange rate limiter.
     lc_updates_by_range_rl: Limiter<PeerId>,
+    fork_context: Arc<ForkContext>,
 }
 
 /// Error type for non conformant requests
@@ -176,7 +178,7 @@ impl RPCRateLimiterBuilder {
         self
     }
 
-    pub fn build(self) -> Result<RPCRateLimiter, &'static str> {
+    pub fn build(self, fork_context: Arc<ForkContext>) -> Result<RPCRateLimiter, &'static str> {
         // get our quotas
         let ping_quota = self.ping_quota.ok_or("Ping quota not specified")?;
         let metadata_quota = self.metadata_quota.ok_or("MetaData quota not specified")?;
@@ -253,13 +255,14 @@ impl RPCRateLimiterBuilder {
             lc_finality_update_rl,
             lc_updates_by_range_rl,
             init_time: Instant::now(),
+            fork_context,
         })
     }
 }
 
 pub trait RateLimiterItem {
     fn protocol(&self) -> Protocol;
-    fn max_responses(&self) -> u64;
+    fn max_responses(&self, current_fork: ForkName, spec: &ChainSpec) -> u64;
 }
 
 impl<E: EthSpec> RateLimiterItem for super::RequestType<E> {
@@ -267,13 +270,16 @@ impl<E: EthSpec> RateLimiterItem for super::RequestType<E> {
         self.versioned_protocol().protocol()
     }
 
-    fn max_responses(&self) -> u64 {
-        self.max_responses()
+    fn max_responses(&self, current_fork: ForkName, spec: &ChainSpec) -> u64 {
+        self.max_responses(current_fork, spec)
     }
 }
 
 impl RPCRateLimiter {
-    pub fn new_with_config(config: RateLimiterConfig) -> Result<Self, &'static str> {
+    pub fn new_with_config(
+        config: RateLimiterConfig,
+        fork_context: Arc<ForkContext>,
+    ) -> Result<Self, &'static str> {
         // Destructure to make sure every configuration value is used.
         let RateLimiterConfig {
             ping_quota,
@@ -316,7 +322,7 @@ impl RPCRateLimiter {
                 Protocol::LightClientUpdatesByRange,
                 light_client_updates_by_range_quota,
             )
-            .build()
+            .build(fork_context)
     }
 
     /// Get a builder instance.
@@ -330,7 +336,9 @@ impl RPCRateLimiter {
         request: &Item,
     ) -> Result<(), RateLimitedErr> {
         let time_since_start = self.init_time.elapsed();
-        let tokens = request.max_responses().max(1);
+        let tokens = request
+            .max_responses(self.fork_context.current_fork(), &self.fork_context.spec)
+            .max(1);
 
         let check =
             |limiter: &mut Limiter<PeerId>| limiter.allows(time_since_start, peer_id, tokens);
diff --git a/beacon_node/lighthouse_network/src/rpc/self_limiter.rs b/beacon_node/lighthouse_network/src/rpc/self_limiter.rs
index e968ad11e3..e0c8593f29 100644
--- a/beacon_node/lighthouse_network/src/rpc/self_limiter.rs
+++ b/beacon_node/lighthouse_network/src/rpc/self_limiter.rs
@@ -1,5 +1,6 @@
 use std::{
     collections::{hash_map::Entry, HashMap, VecDeque},
+    sync::Arc,
     task::{Context, Poll},
     time::Duration,
 };
@@ -9,7 +10,7 @@ use libp2p::{swarm::NotifyHandler, PeerId};
 use slog::{crit, debug, Logger};
 use smallvec::SmallVec;
 use tokio_util::time::DelayQueue;
-use types::EthSpec;
+use types::{EthSpec, ForkContext};
 
 use super::{
     config::OutboundRateLimiterConfig,
@@ -50,9 +51,13 @@ pub enum Error {
 
 impl<Id: ReqId, E: EthSpec> SelfRateLimiter<Id, E> {
     /// Creates a new [`SelfRateLimiter`] based on configration values.
-    pub fn new(config: OutboundRateLimiterConfig, log: Logger) -> Result<Self, &'static str> {
+    pub fn new(
+        config: OutboundRateLimiterConfig,
+        fork_context: Arc<ForkContext>,
+        log: Logger,
+    ) -> Result<Self, &'static str> {
         debug!(log, "Using self rate limiting params"; "config" => ?config);
-        let limiter = RateLimiter::new_with_config(config.0)?;
+        let limiter = RateLimiter::new_with_config(config.0, fork_context)?;
 
         Ok(SelfRateLimiter {
             delayed_requests: Default::default(),
@@ -215,7 +220,7 @@ mod tests {
     use crate::service::api_types::{AppRequestId, RequestId, SyncRequestId};
     use libp2p::PeerId;
     use std::time::Duration;
-    use types::MainnetEthSpec;
+    use types::{EthSpec, ForkContext, Hash256, MainnetEthSpec, Slot};
 
     /// Test that `next_peer_request_ready` correctly maintains the queue.
     #[tokio::test]
@@ -225,8 +230,13 @@ mod tests {
             ping_quota: Quota::n_every(1, 2),
             ..Default::default()
         });
+        let fork_context = std::sync::Arc::new(ForkContext::new::<MainnetEthSpec>(
+            Slot::new(0),
+            Hash256::ZERO,
+            &MainnetEthSpec::default_spec(),
+        ));
         let mut limiter: SelfRateLimiter<RequestId, MainnetEthSpec> =
-            SelfRateLimiter::new(config, log).unwrap();
+            SelfRateLimiter::new(config, fork_context, log).unwrap();
         let peer_id = PeerId::random();
 
         for i in 1..=5u32 {
diff --git a/beacon_node/lighthouse_network/src/service/mod.rs b/beacon_node/lighthouse_network/src/service/mod.rs
index afcbfce173..354def79b0 100644
--- a/beacon_node/lighthouse_network/src/service/mod.rs
+++ b/beacon_node/lighthouse_network/src/service/mod.rs
@@ -16,7 +16,7 @@ use crate::rpc::{
 use crate::types::{
     attestation_sync_committee_topics, fork_core_topics, subnet_from_topic_hash, GossipEncoding,
     GossipKind, GossipTopic, SnappyTransform, Subnet, SubnetDiscovery, ALTAIR_CORE_TOPICS,
-    BASE_CORE_TOPICS, CAPELLA_CORE_TOPICS, DENEB_CORE_TOPICS, LIGHT_CLIENT_GOSSIP_TOPICS,
+    BASE_CORE_TOPICS, CAPELLA_CORE_TOPICS, LIGHT_CLIENT_GOSSIP_TOPICS,
 };
 use crate::EnrExt;
 use crate::Eth2Enr;
@@ -198,15 +198,12 @@ impl<E: EthSpec> Network<E> {
         )?;
 
         // Construct the metadata
-        let custody_subnet_count = ctx.chain_spec.is_peer_das_scheduled().then(|| {
-            if config.subscribe_all_data_column_subnets {
-                ctx.chain_spec.data_column_sidecar_subnet_count
-            } else {
-                ctx.chain_spec.custody_requirement
-            }
+        let custody_group_count = ctx.chain_spec.is_peer_das_scheduled().then(|| {
+            ctx.chain_spec
+                .custody_group_count(config.subscribe_all_data_column_subnets)
         });
         let meta_data =
-            utils::load_or_build_metadata(&config.network_dir, custody_subnet_count, &log);
+            utils::load_or_build_metadata(&config.network_dir, custody_group_count, &log);
         let seq_number = *meta_data.seq_number();
         let globals = NetworkGlobals::new(
             enr,
@@ -285,26 +282,23 @@ impl<E: EthSpec> Network<E> {
 
             let max_topics = ctx.chain_spec.attestation_subnet_count as usize
                 + SYNC_COMMITTEE_SUBNET_COUNT as usize
-                + ctx.chain_spec.blob_sidecar_subnet_count as usize
+                + ctx.chain_spec.blob_sidecar_subnet_count_max() as usize
                 + ctx.chain_spec.data_column_sidecar_subnet_count as usize
                 + BASE_CORE_TOPICS.len()
                 + ALTAIR_CORE_TOPICS.len()
-                + CAPELLA_CORE_TOPICS.len()
-                + DENEB_CORE_TOPICS.len()
+                + CAPELLA_CORE_TOPICS.len() // 0 core deneb and electra topics
                 + LIGHT_CLIENT_GOSSIP_TOPICS.len();
 
             let possible_fork_digests = ctx.fork_context.all_fork_digests();
             let filter = gossipsub::MaxCountSubscriptionFilter {
                 filter: utils::create_whitelist_filter(
                     possible_fork_digests,
-                    ctx.chain_spec.attestation_subnet_count,
+                    &ctx.chain_spec,
                     SYNC_COMMITTEE_SUBNET_COUNT,
-                    ctx.chain_spec.blob_sidecar_subnet_count,
-                    ctx.chain_spec.data_column_sidecar_subnet_count,
                 ),
                 // during a fork we subscribe to both the old and new topics
                 max_subscribed_topics: max_topics * 4,
-                // 418 in theory = (64 attestation + 4 sync committee + 7 core topics + 6 blob topics + 128 column topics) * 2
+                // 424 in theory = (64 attestation + 4 sync committee + 7 core topics + 9 blob topics + 128 column topics) * 2
                 max_subscriptions_per_request: max_topics * 2,
             };
 
@@ -1852,7 +1846,7 @@ impl<E: EthSpec> Network<E> {
                     None
                 }
                 #[allow(unreachable_patterns)]
-                BehaviourEvent::ConnectionLimits(le) => void::unreachable(le),
+                BehaviourEvent::ConnectionLimits(le) => libp2p::core::util::unreachable(le),
             },
             SwarmEvent::ConnectionEstablished { .. } => None,
             SwarmEvent::ConnectionClosed { .. } => None,
diff --git a/beacon_node/lighthouse_network/src/service/utils.rs b/beacon_node/lighthouse_network/src/service/utils.rs
index 490928c08c..72c2b29102 100644
--- a/beacon_node/lighthouse_network/src/service/utils.rs
+++ b/beacon_node/lighthouse_network/src/service/utils.rs
@@ -164,8 +164,8 @@ pub fn strip_peer_id(addr: &mut Multiaddr) {
 
 /// Load metadata from persisted file. Return default metadata if loading fails.
 pub fn load_or_build_metadata<E: EthSpec>(
-    network_dir: &std::path::Path,
-    custody_subnet_count: Option<u64>,
+    network_dir: &Path,
+    custody_group_count_opt: Option<u64>,
     log: &slog::Logger,
 ) -> MetaData<E> {
     // We load a V2 metadata version by default (regardless of current fork)
@@ -216,12 +216,12 @@ pub fn load_or_build_metadata<E: EthSpec>(
     };
 
     // Wrap the MetaData
-    let meta_data = if let Some(custody_count) = custody_subnet_count {
+    let meta_data = if let Some(custody_group_count) = custody_group_count_opt {
         MetaData::V3(MetaDataV3 {
             attnets: meta_data.attnets,
             seq_number: meta_data.seq_number,
             syncnets: meta_data.syncnets,
-            custody_subnet_count: custody_count,
+            custody_group_count,
         })
     } else {
         MetaData::V2(meta_data)
@@ -236,10 +236,8 @@ pub fn load_or_build_metadata<E: EthSpec>(
 /// possible fork digests.
 pub(crate) fn create_whitelist_filter(
     possible_fork_digests: Vec<[u8; 4]>,
-    attestation_subnet_count: u64,
+    spec: &ChainSpec,
     sync_committee_subnet_count: u64,
-    blob_sidecar_subnet_count: u64,
-    data_column_sidecar_subnet_count: u64,
 ) -> gossipsub::WhitelistSubscriptionFilter {
     let mut possible_hashes = HashSet::new();
     for fork_digest in possible_fork_digests {
@@ -259,16 +257,17 @@ pub(crate) fn create_whitelist_filter(
         add(BlsToExecutionChange);
         add(LightClientFinalityUpdate);
         add(LightClientOptimisticUpdate);
-        for id in 0..attestation_subnet_count {
+        for id in 0..spec.attestation_subnet_count {
             add(Attestation(SubnetId::new(id)));
         }
         for id in 0..sync_committee_subnet_count {
             add(SyncCommitteeMessage(SyncSubnetId::new(id)));
         }
-        for id in 0..blob_sidecar_subnet_count {
+        let blob_subnet_count = spec.blob_sidecar_subnet_count_max();
+        for id in 0..blob_subnet_count {
             add(BlobSidecar(id));
         }
-        for id in 0..data_column_sidecar_subnet_count {
+        for id in 0..spec.data_column_sidecar_subnet_count {
             add(DataColumnSidecar(DataColumnSubnetId::new(id)));
         }
     }
@@ -283,8 +282,8 @@ pub(crate) fn save_metadata_to_disk<E: EthSpec>(
 ) {
     let _ = std::fs::create_dir_all(dir);
     // We always store the metadata v2 to disk because
-    // custody_subnet_count parameter doesn't need to be persisted across runs.
-    // custody_subnet_count is what the user sets it for the current run.
+    // custody_group_count parameter doesn't need to be persisted across runs.
+    // custody_group_count is what the user sets it for the current run.
     // This is to prevent ugly branching logic when reading the metadata from disk.
     let metadata_bytes = metadata.metadata_v2().as_ssz_bytes();
     match File::create(dir.join(METADATA_FILENAME)).and_then(|mut f| f.write_all(&metadata_bytes)) {
diff --git a/beacon_node/lighthouse_network/src/types/globals.rs b/beacon_node/lighthouse_network/src/types/globals.rs
index 92583b7b5d..c9e84e2dd1 100644
--- a/beacon_node/lighthouse_network/src/types/globals.rs
+++ b/beacon_node/lighthouse_network/src/types/globals.rs
@@ -3,10 +3,13 @@ use crate::peer_manager::peerdb::PeerDB;
 use crate::rpc::{MetaData, MetaDataV3};
 use crate::types::{BackFillState, SyncState};
 use crate::{Client, Enr, EnrExt, GossipTopic, Multiaddr, NetworkConfig, PeerId};
-use itertools::Itertools;
 use parking_lot::RwLock;
+use slog::error;
 use std::collections::HashSet;
 use std::sync::Arc;
+use types::data_column_custody_group::{
+    compute_columns_for_custody_group, compute_subnets_from_custody_group, get_custody_groups,
+};
 use types::{ChainSpec, ColumnIndex, DataColumnSubnetId, EthSpec};
 
 pub struct NetworkGlobals<E: EthSpec> {
@@ -27,8 +30,8 @@ pub struct NetworkGlobals<E: EthSpec> {
     /// The current state of the backfill sync.
     pub backfill_state: RwLock<BackFillState>,
     /// The computed sampling subnets and columns is stored to avoid re-computing.
-    pub sampling_subnets: Vec<DataColumnSubnetId>,
-    pub sampling_columns: Vec<ColumnIndex>,
+    pub sampling_subnets: HashSet<DataColumnSubnetId>,
+    pub sampling_columns: HashSet<ColumnIndex>,
     /// Network-related configuration. Immutable after initialization.
     pub config: Arc<NetworkConfig>,
     /// Ethereum chain configuration. Immutable after initialization.
@@ -48,30 +51,43 @@ impl<E: EthSpec> NetworkGlobals<E> {
         let (sampling_subnets, sampling_columns) = if spec.is_peer_das_scheduled() {
             let node_id = enr.node_id().raw();
 
-            let custody_subnet_count = local_metadata
-                .custody_subnet_count()
-                .copied()
-                .expect("custody subnet count must be set if PeerDAS is scheduled");
+            let custody_group_count = match local_metadata.custody_group_count() {
+                Ok(&cgc) if cgc <= spec.number_of_custody_groups => cgc,
+                _ => {
+                    error!(
+                        log,
+                        "custody_group_count from metadata is either invalid or not set. This is a bug!";
+                        "info" => "falling back to default custody requirement"
+                    );
+                    spec.custody_requirement
+                }
+            };
 
-            let subnet_sampling_size = std::cmp::max(custody_subnet_count, spec.samples_per_slot);
+            // The below `expect` calls will panic on start up if the chain spec config values used
+            // are invalid
+            let sampling_size = spec
+                .sampling_size(custody_group_count)
+                .expect("should compute node sampling size from valid chain spec");
+            let custody_groups = get_custody_groups(node_id, sampling_size, &spec)
+                .expect("should compute node custody groups");
 
-            let sampling_subnets = DataColumnSubnetId::compute_custody_subnets::<E>(
-                node_id,
-                subnet_sampling_size,
-                &spec,
-            )
-            .expect("sampling subnet count must be valid")
-            .collect::<Vec<_>>();
+            let mut sampling_subnets = HashSet::new();
+            for custody_index in &custody_groups {
+                let subnets = compute_subnets_from_custody_group(*custody_index, &spec)
+                    .expect("should compute custody subnets for node");
+                sampling_subnets.extend(subnets);
+            }
 
-            let sampling_columns = sampling_subnets
-                .iter()
-                .flat_map(|subnet| subnet.columns::<E>(&spec))
-                .sorted()
-                .collect();
+            let mut sampling_columns = HashSet::new();
+            for custody_index in &custody_groups {
+                let columns = compute_columns_for_custody_group(*custody_index, &spec)
+                    .expect("should compute custody columns for node");
+                sampling_columns.extend(columns);
+            }
 
             (sampling_subnets, sampling_columns)
         } else {
-            (vec![], vec![])
+            (HashSet::new(), HashSet::new())
         };
 
         NetworkGlobals {
@@ -159,8 +175,8 @@ impl<E: EthSpec> NetworkGlobals<E> {
     pub fn custody_peers_for_column(&self, column_index: ColumnIndex) -> Vec<PeerId> {
         self.peers
             .read()
-            .good_custody_subnet_peer(DataColumnSubnetId::from_column_index::<E>(
-                column_index as usize,
+            .good_custody_subnet_peer(DataColumnSubnetId::from_column_index(
+                column_index,
                 &self.spec,
             ))
             .cloned()
@@ -178,7 +194,7 @@ impl<E: EthSpec> NetworkGlobals<E> {
             seq_number: 0,
             attnets: Default::default(),
             syncnets: Default::default(),
-            custody_subnet_count: spec.custody_requirement,
+            custody_group_count: spec.custody_requirement,
         });
         Self::new_test_globals_with_metadata(trusted_peers, metadata, log, config, spec)
     }
@@ -207,11 +223,11 @@ mod test {
     fn test_sampling_subnets() {
         let log = logging::test_logger();
         let mut spec = E::default_spec();
-        spec.eip7594_fork_epoch = Some(Epoch::new(0));
+        spec.fulu_fork_epoch = Some(Epoch::new(0));
 
-        let custody_subnet_count = spec.data_column_sidecar_subnet_count / 2;
-        let subnet_sampling_size = std::cmp::max(custody_subnet_count, spec.samples_per_slot);
-        let metadata = get_metadata(custody_subnet_count);
+        let custody_group_count = spec.number_of_custody_groups / 2;
+        let subnet_sampling_size = spec.sampling_size(custody_group_count).unwrap();
+        let metadata = get_metadata(custody_group_count);
         let config = Arc::new(NetworkConfig::default());
 
         let globals = NetworkGlobals::<E>::new_test_globals_with_metadata(
@@ -231,11 +247,11 @@ mod test {
     fn test_sampling_columns() {
         let log = logging::test_logger();
         let mut spec = E::default_spec();
-        spec.eip7594_fork_epoch = Some(Epoch::new(0));
+        spec.fulu_fork_epoch = Some(Epoch::new(0));
 
-        let custody_subnet_count = spec.data_column_sidecar_subnet_count / 2;
-        let subnet_sampling_size = std::cmp::max(custody_subnet_count, spec.samples_per_slot);
-        let metadata = get_metadata(custody_subnet_count);
+        let custody_group_count = spec.number_of_custody_groups / 2;
+        let subnet_sampling_size = spec.sampling_size(custody_group_count).unwrap();
+        let metadata = get_metadata(custody_group_count);
         let config = Arc::new(NetworkConfig::default());
 
         let globals = NetworkGlobals::<E>::new_test_globals_with_metadata(
@@ -251,12 +267,12 @@ mod test {
         );
     }
 
-    fn get_metadata(custody_subnet_count: u64) -> MetaData<E> {
+    fn get_metadata(custody_group_count: u64) -> MetaData<E> {
         MetaData::V3(MetaDataV3 {
             seq_number: 0,
             attnets: Default::default(),
             syncnets: Default::default(),
-            custody_subnet_count,
+            custody_group_count,
         })
     }
 }
diff --git a/beacon_node/lighthouse_network/src/types/mod.rs b/beacon_node/lighthouse_network/src/types/mod.rs
index 6f266fd2ba..a1eedaef74 100644
--- a/beacon_node/lighthouse_network/src/types/mod.rs
+++ b/beacon_node/lighthouse_network/src/types/mod.rs
@@ -18,5 +18,5 @@ pub use sync_state::{BackFillState, SyncState};
 pub use topics::{
     attestation_sync_committee_topics, core_topics_to_subscribe, fork_core_topics,
     subnet_from_topic_hash, GossipEncoding, GossipKind, GossipTopic, ALTAIR_CORE_TOPICS,
-    BASE_CORE_TOPICS, CAPELLA_CORE_TOPICS, DENEB_CORE_TOPICS, LIGHT_CLIENT_GOSSIP_TOPICS,
+    BASE_CORE_TOPICS, CAPELLA_CORE_TOPICS, LIGHT_CLIENT_GOSSIP_TOPICS,
 };
diff --git a/beacon_node/lighthouse_network/src/types/pubsub.rs b/beacon_node/lighthouse_network/src/types/pubsub.rs
index e61ab1bf2d..481540dddb 100644
--- a/beacon_node/lighthouse_network/src/types/pubsub.rs
+++ b/beacon_node/lighthouse_network/src/types/pubsub.rs
@@ -7,15 +7,14 @@ use ssz::{Decode, Encode};
 use std::io::{Error, ErrorKind};
 use std::sync::Arc;
 use types::{
-    Attestation, AttestationBase, AttestationElectra, AttesterSlashing, AttesterSlashingBase,
-    AttesterSlashingElectra, BlobSidecar, DataColumnSidecar, DataColumnSubnetId, EthSpec,
-    ForkContext, ForkName, LightClientFinalityUpdate, LightClientOptimisticUpdate,
-    ProposerSlashing, SignedAggregateAndProof, SignedAggregateAndProofBase,
-    SignedAggregateAndProofElectra, SignedBeaconBlock, SignedBeaconBlockAltair,
-    SignedBeaconBlockBase, SignedBeaconBlockBellatrix, SignedBeaconBlockCapella,
-    SignedBeaconBlockDeneb, SignedBeaconBlockElectra, SignedBlsToExecutionChange,
-    SignedContributionAndProof, SignedInclusionList, SignedVoluntaryExit, SubnetId,
-    SyncCommitteeMessage, SyncSubnetId,
+    Attestation, AttestationBase, AttesterSlashing, AttesterSlashingBase, AttesterSlashingElectra,
+    BlobSidecar, DataColumnSidecar, DataColumnSubnetId, EthSpec, ForkContext, ForkName,
+    LightClientFinalityUpdate, LightClientOptimisticUpdate, ProposerSlashing,
+    SignedAggregateAndProof, SignedAggregateAndProofBase, SignedAggregateAndProofElectra,
+    SignedBeaconBlock, SignedBeaconBlockAltair, SignedBeaconBlockBase, SignedBeaconBlockBellatrix,
+    SignedBeaconBlockCapella, SignedBeaconBlockDeneb, SignedBeaconBlockElectra,
+    SignedBeaconBlockFulu, SignedBlsToExecutionChange, SignedContributionAndProof,
+    SignedVoluntaryExit, SingleAttestation, SubnetId, SyncCommitteeMessage, SyncSubnetId, SignedInclusionList,
 };
 
 #[derive(Debug, Clone, PartialEq)]
@@ -28,8 +27,10 @@ pub enum PubsubMessage<E: EthSpec> {
     DataColumnSidecar(Box<(DataColumnSubnetId, Arc<DataColumnSidecar<E>>)>),
     /// Gossipsub message providing notification of a Aggregate attestation and associated proof.
     AggregateAndProofAttestation(Box<SignedAggregateAndProof<E>>),
-    /// Gossipsub message providing notification of a raw un-aggregated attestation with its shard id.
+    /// Gossipsub message providing notification of a raw un-aggregated attestation with its subnet id.
     Attestation(Box<(SubnetId, Attestation<E>)>),
+    /// Gossipsub message providing notification of a `SingleAttestation`` with its subnet id.
+    SingleAttestation(Box<(SubnetId, SingleAttestation)>),
     /// Gossipsub message providing notification of a voluntary exit.
     VoluntaryExit(Box<SignedVoluntaryExit>),
     /// Gossipsub message providing notification of a new proposer slashing.
@@ -131,6 +132,9 @@ impl<E: EthSpec> PubsubMessage<E> {
             PubsubMessage::Attestation(attestation_data) => {
                 GossipKind::Attestation(attestation_data.0)
             }
+            PubsubMessage::SingleAttestation(attestation_data) => {
+                GossipKind::Attestation(attestation_data.0)
+            }
             PubsubMessage::VoluntaryExit(_) => GossipKind::VoluntaryExit,
             PubsubMessage::ProposerSlashing(_) => GossipKind::ProposerSlashing,
             PubsubMessage::AttesterSlashing(_) => GossipKind::AttesterSlashing,
@@ -192,32 +196,32 @@ impl<E: EthSpec> PubsubMessage<E> {
                         )))
                     }
                     GossipKind::Attestation(subnet_id) => {
-                        let attestation =
-                            match fork_context.from_context_bytes(gossip_topic.fork_digest) {
-                                Some(&fork_name) => {
-                                    if fork_name.electra_enabled() {
-                                        Attestation::Electra(
-                                            AttestationElectra::from_ssz_bytes(data)
-                                                .map_err(|e| format!("{:?}", e))?,
-                                        )
-                                    } else {
-                                        Attestation::Base(
-                                            AttestationBase::from_ssz_bytes(data)
-                                                .map_err(|e| format!("{:?}", e))?,
-                                        )
-                                    }
+                        match fork_context.from_context_bytes(gossip_topic.fork_digest) {
+                            Some(&fork_name) => {
+                                if fork_name.electra_enabled() {
+                                    let single_attestation =
+                                        SingleAttestation::from_ssz_bytes(data)
+                                            .map_err(|e| format!("{:?}", e))?;
+                                    Ok(PubsubMessage::SingleAttestation(Box::new((
+                                        *subnet_id,
+                                        single_attestation,
+                                    ))))
+                                } else {
+                                    let attestation = Attestation::Base(
+                                        AttestationBase::from_ssz_bytes(data)
+                                            .map_err(|e| format!("{:?}", e))?,
+                                    );
+                                    Ok(PubsubMessage::Attestation(Box::new((
+                                        *subnet_id,
+                                        attestation,
+                                    ))))
                                 }
-                                None => {
-                                    return Err(format!(
-                                        "Unknown gossipsub fork digest: {:?}",
-                                        gossip_topic.fork_digest
-                                    ))
-                                }
-                            };
-                        Ok(PubsubMessage::Attestation(Box::new((
-                            *subnet_id,
-                            attestation,
-                        ))))
+                            }
+                            None => Err(format!(
+                                "Unknown gossipsub fork digest: {:?}",
+                                gossip_topic.fork_digest
+                            )),
+                        }
                     }
                     GossipKind::BeaconBlock => {
                         let beacon_block =
@@ -246,6 +250,10 @@ impl<E: EthSpec> PubsubMessage<E> {
                                     SignedBeaconBlockElectra::from_ssz_bytes(data)
                                         .map_err(|e| format!("{:?}", e))?,
                                 ),
+                                Some(ForkName::Fulu) => SignedBeaconBlock::<E>::Fulu(
+                                    SignedBeaconBlockFulu::from_ssz_bytes(data)
+                                        .map_err(|e| format!("{:?}", e))?,
+                                ),
                                 None => {
                                     return Err(format!(
                                         "Unknown gossipsub fork digest: {:?}",
@@ -278,27 +286,15 @@ impl<E: EthSpec> PubsubMessage<E> {
                     }
                     GossipKind::DataColumnSidecar(subnet_id) => {
                         match fork_context.from_context_bytes(gossip_topic.fork_digest) {
-                            // TODO(das): Remove Deneb fork
-                            Some(fork) if fork.deneb_enabled() => {
+                            Some(fork) if fork.fulu_enabled() => {
                                 let col_sidecar = Arc::new(
                                     DataColumnSidecar::from_ssz_bytes(data)
                                         .map_err(|e| format!("{:?}", e))?,
                                 );
-                                let peer_das_enabled =
-                                    fork_context.spec.is_peer_das_enabled_for_epoch(
-                                        col_sidecar.slot().epoch(E::slots_per_epoch()),
-                                    );
-                                if peer_das_enabled {
-                                    Ok(PubsubMessage::DataColumnSidecar(Box::new((
-                                        *subnet_id,
-                                        col_sidecar,
-                                    ))))
-                                } else {
-                                    Err(format!(
-                                        "data_column_sidecar topic invalid for given fork digest {:?}",
-                                        gossip_topic.fork_digest
-                                    ))
-                                }
+                                Ok(PubsubMessage::DataColumnSidecar(Box::new((
+                                    *subnet_id,
+                                    col_sidecar,
+                                ))))
                             }
                             Some(_) | None => Err(format!(
                                 "data_column_sidecar topic invalid for given fork digest {:?}",
@@ -438,6 +434,7 @@ impl<E: EthSpec> PubsubMessage<E> {
             PubsubMessage::ProposerSlashing(data) => data.as_ssz_bytes(),
             PubsubMessage::AttesterSlashing(data) => data.as_ssz_bytes(),
             PubsubMessage::Attestation(data) => data.1.as_ssz_bytes(),
+            PubsubMessage::SingleAttestation(data) => data.1.as_ssz_bytes(),
             PubsubMessage::SignedContributionAndProof(data) => data.as_ssz_bytes(),
             PubsubMessage::SyncCommitteeMessage(data) => data.1.as_ssz_bytes(),
             PubsubMessage::BlsToExecutionChange(data) => data.as_ssz_bytes(),
@@ -483,6 +480,14 @@ impl<E: EthSpec> std::fmt::Display for PubsubMessage<E> {
                 data.1.data().slot,
                 data.1.committee_index(),
             ),
+            PubsubMessage::SingleAttestation(data) => write!(
+                f,
+                "SingleAttestation: subnet_id: {}, attestation_slot: {}, committee_index: {:?}, attester_index: {:?}",
+                *data.0,
+                data.1.data.slot,
+                data.1.committee_index,
+                data.1.attester_index,
+            ),
             PubsubMessage::VoluntaryExit(_data) => write!(f, "Voluntary Exit"),
             PubsubMessage::ProposerSlashing(_data) => write!(f, "Proposer Slashing"),
             PubsubMessage::AttesterSlashing(_data) => write!(f, "Attester Slashing"),
diff --git a/beacon_node/lighthouse_network/src/types/topics.rs b/beacon_node/lighthouse_network/src/types/topics.rs
index 6970218883..a61da2e8fb 100644
--- a/beacon_node/lighthouse_network/src/types/topics.rs
+++ b/beacon_node/lighthouse_network/src/types/topics.rs
@@ -42,10 +42,6 @@ pub const LIGHT_CLIENT_GOSSIP_TOPICS: [GossipKind; 2] = [
     GossipKind::LightClientOptimisticUpdate,
 ];
 
-pub const DENEB_CORE_TOPICS: [GossipKind; 0] = [];
-
-pub const ELECTRA_CORE_TOPICS: [GossipKind; 1] = [GossipKind::InclusionList];
-
 /// Returns the core topics associated with each fork that are new to the previous fork
 pub fn fork_core_topics<E: EthSpec>(fork_name: &ForkName, spec: &ChainSpec) -> Vec<GossipKind> {
     match fork_name {
@@ -56,14 +52,24 @@ pub fn fork_core_topics<E: EthSpec>(fork_name: &ForkName, spec: &ChainSpec) -> V
         ForkName::Deneb => {
             // All of deneb blob topics are core topics
             let mut deneb_blob_topics = Vec::new();
-            for i in 0..spec.blob_sidecar_subnet_count {
+            for i in 0..spec.blob_sidecar_subnet_count(ForkName::Deneb) {
                 deneb_blob_topics.push(GossipKind::BlobSidecar(i));
             }
-            let mut deneb_topics = DENEB_CORE_TOPICS.to_vec();
-            deneb_topics.append(&mut deneb_blob_topics);
-            deneb_topics
+            deneb_blob_topics
         }
-        ForkName::Electra => ELECTRA_CORE_TOPICS.to_vec(),
+        ForkName::Electra => {
+            // All of electra blob topics are core topics
+            let mut electra_blob_topics = Vec::new();
+            for i in 0..spec.blob_sidecar_subnet_count(ForkName::Electra) {
+                electra_blob_topics.push(GossipKind::BlobSidecar(i));
+            }
+
+            if spec.is_focil_scheduled() {
+                electra_blob_topics.push(GossipKind::InclusionList)
+            }
+            electra_blob_topics
+        }
+        ForkName::Fulu => vec![],
     }
 }
 
@@ -90,7 +96,12 @@ pub fn core_topics_to_subscribe<E: EthSpec>(
         topics.extend(previous_fork_topics);
         current_fork = previous_fork;
     }
+    // Remove duplicates
     topics
+        .into_iter()
+        .collect::<std::collections::HashSet<_>>()
+        .into_iter()
+        .collect()
 }
 
 /// A gossipsub topic which encapsulates the type of messages that should be sent and received over
@@ -473,16 +484,19 @@ mod tests {
         type E = MainnetEthSpec;
         let spec = E::default_spec();
         let mut all_topics = Vec::new();
+        let mut electra_core_topics = fork_core_topics::<E>(&ForkName::Electra, &spec);
         let mut deneb_core_topics = fork_core_topics::<E>(&ForkName::Deneb, &spec);
+        all_topics.append(&mut electra_core_topics);
         all_topics.append(&mut deneb_core_topics);
         all_topics.extend(CAPELLA_CORE_TOPICS);
         all_topics.extend(ALTAIR_CORE_TOPICS);
         all_topics.extend(BASE_CORE_TOPICS);
 
         let latest_fork = *ForkName::list_all().last().unwrap();
-        assert_eq!(
-            core_topics_to_subscribe::<E>(latest_fork, &spec),
-            all_topics
-        );
+        let core_topics = core_topics_to_subscribe::<E>(latest_fork, &spec);
+        // Need to check all the topics exist in an order independent manner
+        for topic in all_topics {
+            assert!(core_topics.contains(&topic));
+        }
     }
 }
diff --git a/beacon_node/lighthouse_network/tests/common.rs b/beacon_node/lighthouse_network/tests/common.rs
index 84e19c81d0..6a3ec6dd32 100644
--- a/beacon_node/lighthouse_network/tests/common.rs
+++ b/beacon_node/lighthouse_network/tests/common.rs
@@ -25,12 +25,14 @@ pub fn fork_context(fork_name: ForkName) -> ForkContext {
     let capella_fork_epoch = Epoch::new(3);
     let deneb_fork_epoch = Epoch::new(4);
     let electra_fork_epoch = Epoch::new(5);
+    let fulu_fork_epoch = Epoch::new(6);
 
     chain_spec.altair_fork_epoch = Some(altair_fork_epoch);
     chain_spec.bellatrix_fork_epoch = Some(bellatrix_fork_epoch);
     chain_spec.capella_fork_epoch = Some(capella_fork_epoch);
     chain_spec.deneb_fork_epoch = Some(deneb_fork_epoch);
     chain_spec.electra_fork_epoch = Some(electra_fork_epoch);
+    chain_spec.fulu_fork_epoch = Some(fulu_fork_epoch);
 
     let current_slot = match fork_name {
         ForkName::Base => Slot::new(0),
@@ -39,6 +41,7 @@ pub fn fork_context(fork_name: ForkName) -> ForkContext {
         ForkName::Capella => capella_fork_epoch.start_slot(E::slots_per_epoch()),
         ForkName::Deneb => deneb_fork_epoch.start_slot(E::slots_per_epoch()),
         ForkName::Electra => electra_fork_epoch.start_slot(E::slots_per_epoch()),
+        ForkName::Fulu => fulu_fork_epoch.start_slot(E::slots_per_epoch()),
     };
     ForkContext::new::<E>(current_slot, Hash256::zero(), &chain_spec)
 }
diff --git a/beacon_node/lighthouse_network/tests/rpc_tests.rs b/beacon_node/lighthouse_network/tests/rpc_tests.rs
index f721c8477c..4b54a24ddc 100644
--- a/beacon_node/lighthouse_network/tests/rpc_tests.rs
+++ b/beacon_node/lighthouse_network/tests/rpc_tests.rs
@@ -16,7 +16,7 @@ use tokio::time::sleep;
 use types::{
     BeaconBlock, BeaconBlockAltair, BeaconBlockBase, BeaconBlockBellatrix, BlobSidecar, ChainSpec,
     EmptyBlock, Epoch, EthSpec, FixedBytesExtended, ForkContext, ForkName, Hash256, MinimalEthSpec,
-    Signature, SignedBeaconBlock, Slot,
+    RuntimeVariableList, Signature, SignedBeaconBlock, Slot,
 };
 
 type E = MinimalEthSpec;
@@ -810,17 +810,20 @@ fn test_tcp_blocks_by_root_chunked_rpc() {
         .await;
 
         // BlocksByRoot Request
-        let rpc_request = RequestType::BlocksByRoot(BlocksByRootRequest::new(
-            vec![
-                Hash256::zero(),
-                Hash256::zero(),
-                Hash256::zero(),
-                Hash256::zero(),
-                Hash256::zero(),
-                Hash256::zero(),
-            ],
-            &spec,
-        ));
+        let rpc_request =
+            RequestType::BlocksByRoot(BlocksByRootRequest::V2(BlocksByRootRequestV2 {
+                block_roots: RuntimeVariableList::from_vec(
+                    vec![
+                        Hash256::zero(),
+                        Hash256::zero(),
+                        Hash256::zero(),
+                        Hash256::zero(),
+                        Hash256::zero(),
+                        Hash256::zero(),
+                    ],
+                    spec.max_request_blocks_upper_bound(),
+                ),
+            }));
 
         // BlocksByRoot Response
         let full_block = BeaconBlock::Base(BeaconBlockBase::<E>::full(&spec));
@@ -953,21 +956,24 @@ fn test_tcp_blocks_by_root_chunked_rpc_terminates_correctly() {
         .await;
 
         // BlocksByRoot Request
-        let rpc_request = RequestType::BlocksByRoot(BlocksByRootRequest::new(
-            vec![
-                Hash256::zero(),
-                Hash256::zero(),
-                Hash256::zero(),
-                Hash256::zero(),
-                Hash256::zero(),
-                Hash256::zero(),
-                Hash256::zero(),
-                Hash256::zero(),
-                Hash256::zero(),
-                Hash256::zero(),
-            ],
-            &spec,
-        ));
+        let rpc_request =
+            RequestType::BlocksByRoot(BlocksByRootRequest::V2(BlocksByRootRequestV2 {
+                block_roots: RuntimeVariableList::from_vec(
+                    vec![
+                        Hash256::zero(),
+                        Hash256::zero(),
+                        Hash256::zero(),
+                        Hash256::zero(),
+                        Hash256::zero(),
+                        Hash256::zero(),
+                        Hash256::zero(),
+                        Hash256::zero(),
+                        Hash256::zero(),
+                        Hash256::zero(),
+                    ],
+                    spec.max_request_blocks_upper_bound(),
+                ),
+            }));
 
         // BlocksByRoot Response
         let full_block = BeaconBlock::Base(BeaconBlockBase::<E>::full(&spec));
diff --git a/beacon_node/network/Cargo.toml b/beacon_node/network/Cargo.toml
index 44f6c54bbc..09179c4a51 100644
--- a/beacon_node/network/Cargo.toml
+++ b/beacon_node/network/Cargo.toml
@@ -31,7 +31,7 @@ execution_layer = { workspace = true }
 fnv = { workspace = true }
 futures = { workspace = true }
 hex = { workspace = true }
-igd-next = "0.14"
+igd-next = { version = "0.16", features = ["aio_tokio"] }
 itertools = { workspace = true }
 lighthouse_network = { workspace = true }
 logging = { workspace = true }
diff --git a/beacon_node/network/src/network_beacon_processor/gossip_methods.rs b/beacon_node/network/src/network_beacon_processor/gossip_methods.rs
index 8640df38e1..bab0b7a07e 100644
--- a/beacon_node/network/src/network_beacon_processor/gossip_methods.rs
+++ b/beacon_node/network/src/network_beacon_processor/gossip_methods.rs
@@ -1293,13 +1293,12 @@ impl<T: BeaconChainTypes> NetworkBeaconProcessor<T> {
             Err(e @ BlockError::StateRootMismatch { .. })
             | Err(e @ BlockError::IncorrectBlockProposer { .. })
             | Err(e @ BlockError::BlockSlotLimitReached)
-            | Err(e @ BlockError::ProposalSignatureInvalid)
             | Err(e @ BlockError::NonLinearSlots)
             | Err(e @ BlockError::UnknownValidator(_))
             | Err(e @ BlockError::PerBlockProcessingError(_))
             | Err(e @ BlockError::NonLinearParentRoots)
             | Err(e @ BlockError::BlockIsNotLaterThanParent { .. })
-            | Err(e @ BlockError::InvalidSignature)
+            | Err(e @ BlockError::InvalidSignature(_))
             | Err(e @ BlockError::WeakSubjectivityConflict)
             | Err(e @ BlockError::InconsistentFork(_))
             | Err(e @ BlockError::ExecutionPayloadError(_))
@@ -3166,7 +3165,7 @@ impl<T: BeaconChainTypes> NetworkBeaconProcessor<T> {
             .chain
             .slot_clock
             .now()
-            .map_or(false, |current_slot| sync_message_slot == current_slot);
+            .is_some_and(|current_slot| sync_message_slot == current_slot);
 
         self.propagate_if_timely(is_timely, message_id, peer_id)
     }
diff --git a/beacon_node/network/src/network_beacon_processor/mod.rs b/beacon_node/network/src/network_beacon_processor/mod.rs
index 49564657d1..12d3f41465 100644
--- a/beacon_node/network/src/network_beacon_processor/mod.rs
+++ b/beacon_node/network/src/network_beacon_processor/mod.rs
@@ -84,6 +84,58 @@ impl<T: BeaconChainTypes> NetworkBeaconProcessor<T> {
             .map_err(Into::into)
     }
 
+    /// Create a new `Work` event for some `SingleAttestation`.
+    pub fn send_single_attestation(
+        self: &Arc<Self>,
+        message_id: MessageId,
+        peer_id: PeerId,
+        single_attestation: SingleAttestation,
+        subnet_id: SubnetId,
+        should_import: bool,
+        seen_timestamp: Duration,
+    ) -> Result<(), Error<T::EthSpec>> {
+        let result = self.chain.with_committee_cache(
+            single_attestation.data.target.root,
+            single_attestation
+                .data
+                .slot
+                .epoch(T::EthSpec::slots_per_epoch()),
+            |committee_cache, _| {
+                let Some(committee) = committee_cache.get_beacon_committee(
+                    single_attestation.data.slot,
+                    single_attestation.committee_index,
+                ) else {
+                    warn!(
+                        self.log,
+                        "No beacon committee for slot and index";
+                        "slot" => single_attestation.data.slot,
+                        "index" => single_attestation.committee_index
+                    );
+                    return Ok(Ok(()));
+                };
+
+                let attestation = single_attestation.to_attestation(committee.committee)?;
+
+                Ok(self.send_unaggregated_attestation(
+                    message_id.clone(),
+                    peer_id,
+                    attestation,
+                    subnet_id,
+                    should_import,
+                    seen_timestamp,
+                ))
+            },
+        );
+
+        match result {
+            Ok(result) => result,
+            Err(e) => {
+                warn!(self.log, "Failed to send SingleAttestation"; "error" => ?e);
+                Ok(())
+            }
+        }
+    }
+
     /// Create a new `Work` event for some unaggregated attestation.
     pub fn send_unaggregated_attestation(
         self: &Arc<Self>,
@@ -585,6 +637,11 @@ impl<T: BeaconChainTypes> NetworkBeaconProcessor<T> {
         blocks: Vec<RpcBlock<T::EthSpec>>,
     ) -> Result<(), Error<T::EthSpec>> {
         let is_backfill = matches!(&process_id, ChainSegmentProcessId::BackSyncBatchId { .. });
+        debug!(self.log, "Batch sending for process";
+            "blocks" => blocks.len(),
+            "id" => ?process_id,
+        );
+
         let processor = self.clone();
         let process_fn = async move {
             let notify_execution_layer = if processor
@@ -1146,10 +1203,8 @@ impl<T: BeaconChainTypes> NetworkBeaconProcessor<T> {
                         messages: columns
                             .into_iter()
                             .map(|d| {
-                                let subnet = DataColumnSubnetId::from_column_index::<T::EthSpec>(
-                                    d.index as usize,
-                                    &chain.spec,
-                                );
+                                let subnet =
+                                    DataColumnSubnetId::from_column_index(d.index, &chain.spec);
                                 PubsubMessage::DataColumnSidecar(Box::new((subnet, d)))
                             })
                             .collect(),
@@ -1163,7 +1218,8 @@ impl<T: BeaconChainTypes> NetworkBeaconProcessor<T> {
 
                 let blob_publication_batch_interval = chain.config.blob_publication_batch_interval;
                 let blob_publication_batches = chain.config.blob_publication_batches;
-                let batch_size = chain.spec.number_of_columns / blob_publication_batches;
+                let number_of_columns = chain.spec.number_of_columns as usize;
+                let batch_size = number_of_columns / blob_publication_batches;
                 let mut publish_count = 0usize;
 
                 for batch in data_columns_to_publish.chunks(batch_size) {
diff --git a/beacon_node/network/src/network_beacon_processor/rpc_methods.rs b/beacon_node/network/src/network_beacon_processor/rpc_methods.rs
index c4944078fe..67a1570275 100644
--- a/beacon_node/network/src/network_beacon_processor/rpc_methods.rs
+++ b/beacon_node/network/src/network_beacon_processor/rpc_methods.rs
@@ -659,24 +659,6 @@ impl<T: BeaconChainTypes> NetworkBeaconProcessor<T> {
             "start_slot" => req.start_slot(),
         );
 
-        // Should not send more than max request blocks
-        let max_request_size =
-            self.chain
-                .epoch()
-                .map_or(self.chain.spec.max_request_blocks, |epoch| {
-                    if self.chain.spec.fork_name_at_epoch(epoch).deneb_enabled() {
-                        self.chain.spec.max_request_blocks_deneb
-                    } else {
-                        self.chain.spec.max_request_blocks
-                    }
-                });
-        if *req.count() > max_request_size {
-            return Err((
-                RpcErrorResponse::InvalidRequest,
-                "Request exceeded max size",
-            ));
-        }
-
         let forwards_block_root_iter = match self
             .chain
             .forwards_iter_block_roots(Slot::from(*req.start_slot()))
@@ -890,14 +872,6 @@ impl<T: BeaconChainTypes> NetworkBeaconProcessor<T> {
             "start_slot" => req.start_slot,
         );
 
-        // Should not send more than max request blocks
-        if req.max_blobs_requested::<T::EthSpec>() > self.chain.spec.max_request_blob_sidecars {
-            return Err((
-                RpcErrorResponse::InvalidRequest,
-                "Request exceeded `MAX_REQUEST_BLOBS_SIDECARS`",
-            ));
-        }
-
         let request_start_slot = Slot::from(req.start_slot);
 
         let data_availability_boundary_slot = match self.chain.data_availability_boundary() {
diff --git a/beacon_node/network/src/network_beacon_processor/tests.rs b/beacon_node/network/src/network_beacon_processor/tests.rs
index 7e27a91bd6..8415ece638 100644
--- a/beacon_node/network/src/network_beacon_processor/tests.rs
+++ b/beacon_node/network/src/network_beacon_processor/tests.rs
@@ -15,7 +15,7 @@ use beacon_chain::test_utils::{
 use beacon_chain::{BeaconChain, WhenSlotSkipped};
 use beacon_processor::{work_reprocessing_queue::*, *};
 use lighthouse_network::discovery::ConnectionId;
-use lighthouse_network::rpc::methods::BlobsByRangeRequest;
+use lighthouse_network::rpc::methods::{BlobsByRangeRequest, MetaDataV3};
 use lighthouse_network::rpc::{RequestId, SubstreamId};
 use lighthouse_network::{
     discv5::enr::{self, CombinedKey},
@@ -198,11 +198,21 @@ impl TestRig {
         let (sync_tx, _sync_rx) = mpsc::unbounded_channel();
 
         // Default metadata
-        let meta_data = MetaData::V2(MetaDataV2 {
-            seq_number: SEQ_NUMBER,
-            attnets: EnrAttestationBitfield::<MainnetEthSpec>::default(),
-            syncnets: EnrSyncCommitteeBitfield::<MainnetEthSpec>::default(),
-        });
+        let meta_data = if spec.is_peer_das_scheduled() {
+            MetaData::V3(MetaDataV3 {
+                seq_number: SEQ_NUMBER,
+                attnets: EnrAttestationBitfield::<MainnetEthSpec>::default(),
+                syncnets: EnrSyncCommitteeBitfield::<MainnetEthSpec>::default(),
+                custody_group_count: spec.custody_requirement,
+            })
+        } else {
+            MetaData::V2(MetaDataV2 {
+                seq_number: SEQ_NUMBER,
+                attnets: EnrAttestationBitfield::<MainnetEthSpec>::default(),
+                syncnets: EnrSyncCommitteeBitfield::<MainnetEthSpec>::default(),
+            })
+        };
+
         let enr_key = CombinedKey::generate_secp256k1();
         let enr = enr::Enr::builder().build(&enr_key).unwrap();
         let network_config = Arc::new(NetworkConfig::default());
@@ -259,7 +269,7 @@ impl TestRig {
         assert!(beacon_processor.is_ok());
         let block = next_block_tuple.0;
         let blob_sidecars = if let Some((kzg_proofs, blobs)) = next_block_tuple.1 {
-            Some(BlobSidecar::build_sidecars(blobs, &block, kzg_proofs).unwrap())
+            Some(BlobSidecar::build_sidecars(blobs, &block, kzg_proofs, &chain.spec).unwrap())
         } else {
             None
         };
@@ -342,15 +352,16 @@ impl TestRig {
             )
             .unwrap();
     }
+
     pub fn enqueue_single_lookup_rpc_blobs(&self) {
         if let Some(blobs) = self.next_blobs.clone() {
-            let blobs = FixedBlobSidecarList::from(blobs.into_iter().map(Some).collect::<Vec<_>>());
+            let blobs = FixedBlobSidecarList::new(blobs.into_iter().map(Some).collect::<Vec<_>>());
             self.network_beacon_processor
                 .send_rpc_blobs(
                     self.next_block.canonical_root(),
                     blobs,
                     std::time::Duration::default(),
-                    BlockProcessType::SingleBlock { id: 1 },
+                    BlockProcessType::SingleBlob { id: 1 },
                 )
                 .unwrap();
         }
@@ -1130,7 +1141,12 @@ async fn test_blobs_by_range() {
             .block_root_at_slot(Slot::new(slot), WhenSlotSkipped::None)
             .unwrap();
         blob_count += root
-            .map(|root| rig.chain.get_blobs(&root).unwrap_or_default().len())
+            .map(|root| {
+                rig.chain
+                    .get_blobs(&root)
+                    .map(|list| list.len())
+                    .unwrap_or(0)
+            })
             .unwrap_or(0);
     }
     let mut actual_count = 0;
diff --git a/beacon_node/network/src/router.rs b/beacon_node/network/src/router.rs
index 76291f378f..f9ec96df87 100644
--- a/beacon_node/network/src/router.rs
+++ b/beacon_node/network/src/router.rs
@@ -28,7 +28,7 @@ use std::sync::Arc;
 use std::time::{Duration, SystemTime, UNIX_EPOCH};
 use tokio::sync::mpsc;
 use tokio_stream::wrappers::UnboundedReceiverStream;
-use types::{BlobSidecar, DataColumnSidecar, EthSpec, SignedBeaconBlock};
+use types::{BlobSidecar, DataColumnSidecar, EthSpec, ForkContext, SignedBeaconBlock};
 
 /// Handles messages from the network and routes them to the appropriate service to be handled.
 pub struct Router<T: BeaconChainTypes> {
@@ -90,6 +90,7 @@ impl<T: BeaconChainTypes> Router<T> {
         invalid_block_storage: InvalidBlockStorage,
         beacon_processor_send: BeaconProcessorSend<T::EthSpec>,
         beacon_processor_reprocess_tx: mpsc::Sender<ReprocessQueueMessage>,
+        fork_context: Arc<ForkContext>,
         log: slog::Logger,
     ) -> Result<mpsc::UnboundedSender<RouterMessage<T::EthSpec>>, String> {
         let message_handler_log = log.new(o!("service"=> "router"));
@@ -122,6 +123,7 @@ impl<T: BeaconChainTypes> Router<T> {
             network_send.clone(),
             network_beacon_processor.clone(),
             sync_recv,
+            fork_context,
             sync_logger,
         );
 
@@ -398,6 +400,17 @@ impl<T: BeaconChainTypes> Router<T> {
                         timestamp_now(),
                     ),
                 ),
+            PubsubMessage::SingleAttestation(subnet_attestation) => self
+                .handle_beacon_processor_send_result(
+                    self.network_beacon_processor.send_single_attestation(
+                        message_id,
+                        peer_id,
+                        subnet_attestation.1,
+                        subnet_attestation.0,
+                        should_process,
+                        timestamp_now(),
+                    ),
+                ),
             PubsubMessage::BeaconBlock(block) => self.handle_beacon_processor_send_result(
                 self.network_beacon_processor.send_gossip_beacon_block(
                     message_id,
diff --git a/beacon_node/network/src/service.rs b/beacon_node/network/src/service.rs
index 7826807e03..49f73bf9c8 100644
--- a/beacon_node/network/src/service.rs
+++ b/beacon_node/network/src/service.rs
@@ -312,6 +312,7 @@ impl<T: BeaconChainTypes> NetworkService<T> {
             invalid_block_storage,
             beacon_processor_send,
             beacon_processor_reprocess_tx,
+            fork_context.clone(),
             network_log.clone(),
         )?;
 
@@ -549,7 +550,23 @@ impl<T: BeaconChainTypes> NetworkService<T> {
                         // the attestation, else we just just propagate the Attestation.
                         let should_process = self.subnet_service.should_process_attestation(
                             Subnet::Attestation(subnet_id),
-                            attestation,
+                            attestation.data(),
+                        );
+                        self.send_to_router(RouterMessage::PubsubMessage(
+                            id,
+                            source,
+                            message,
+                            should_process,
+                        ));
+                    }
+                    PubsubMessage::SingleAttestation(ref subnet_and_attestation) => {
+                        let subnet_id = subnet_and_attestation.0;
+                        let single_attestation = &subnet_and_attestation.1;
+                        // checks if we have an aggregator for the slot. If so, we should process
+                        // the attestation, else we just just propagate the Attestation.
+                        let should_process = self.subnet_service.should_process_attestation(
+                            Subnet::Attestation(subnet_id),
+                            &single_attestation.data,
                         );
                         self.send_to_router(RouterMessage::PubsubMessage(
                             id,
@@ -734,11 +751,6 @@ impl<T: BeaconChainTypes> NetworkService<T> {
                     }
                 }
 
-                // TODO(das): This is added here for the purpose of testing, *without* having to
-                // activate Electra. This should happen as part of the Electra upgrade and we should
-                // move the subscription logic once it's ready to rebase PeerDAS on Electra, or if
-                // we decide to activate via the soft fork route:
-                // https://github.com/sigp/lighthouse/pull/5899
                 if self.fork_context.spec.is_peer_das_scheduled() {
                     self.subscribe_to_peer_das_topics(&mut subscribed_topics);
                 }
@@ -789,32 +801,32 @@ impl<T: BeaconChainTypes> NetworkService<T> {
         }
     }
 
+    /// Keeping these separate from core topics because it has custom logic:
+    /// 1. Data column subscription logic depends on subscription configuration.
+    /// 2. Data column topic subscriptions will be dynamic based on validator balances due to
+    ///    validator custody.
+    ///
+    /// TODO(das): The downside with not including it in core fork topic is - we subscribe to
+    /// PeerDAS topics on startup if Fulu is scheduled, rather than waiting until the fork.
+    /// If this is an issue we could potentially consider adding the logic to
+    /// `network.subscribe_new_fork_topics()`.
     fn subscribe_to_peer_das_topics(&mut self, subscribed_topics: &mut Vec<GossipTopic>) {
-        if self.subscribe_all_data_column_subnets {
-            for column_subnet in 0..self.fork_context.spec.data_column_sidecar_subnet_count {
-                for fork_digest in self.required_gossip_fork_digests() {
-                    let gossip_kind =
-                        Subnet::DataColumn(DataColumnSubnetId::new(column_subnet)).into();
-                    let topic =
-                        GossipTopic::new(gossip_kind, GossipEncoding::default(), fork_digest);
-                    if self.libp2p.subscribe(topic.clone()) {
-                        subscribed_topics.push(topic);
-                    } else {
-                        warn!(self.log, "Could not subscribe to topic"; "topic" => %topic);
-                    }
-                }
-            }
+        let column_subnets_to_subscribe = if self.subscribe_all_data_column_subnets {
+            &(0..self.fork_context.spec.data_column_sidecar_subnet_count)
+                .map(DataColumnSubnetId::new)
+                .collect()
         } else {
-            for column_subnet in &self.network_globals.sampling_subnets {
-                for fork_digest in self.required_gossip_fork_digests() {
-                    let gossip_kind = Subnet::DataColumn(*column_subnet).into();
-                    let topic =
-                        GossipTopic::new(gossip_kind, GossipEncoding::default(), fork_digest);
-                    if self.libp2p.subscribe(topic.clone()) {
-                        subscribed_topics.push(topic);
-                    } else {
-                        warn!(self.log, "Could not subscribe to topic"; "topic" => %topic);
-                    }
+            &self.network_globals.sampling_subnets
+        };
+
+        for column_subnet in column_subnets_to_subscribe.iter() {
+            for fork_digest in self.required_gossip_fork_digests() {
+                let gossip_kind = Subnet::DataColumn(*column_subnet).into();
+                let topic = GossipTopic::new(gossip_kind, GossipEncoding::default(), fork_digest);
+                if self.libp2p.subscribe(topic.clone()) {
+                    subscribed_topics.push(topic);
+                } else {
+                    warn!(self.log, "Could not subscribe to topic"; "topic" => %topic);
                 }
             }
         }
diff --git a/beacon_node/network/src/subnet_service/mod.rs b/beacon_node/network/src/subnet_service/mod.rs
index da1f220f04..33ae567eb3 100644
--- a/beacon_node/network/src/subnet_service/mod.rs
+++ b/beacon_node/network/src/subnet_service/mod.rs
@@ -17,7 +17,7 @@ use lighthouse_network::{discv5::enr::NodeId, NetworkConfig, Subnet, SubnetDisco
 use slog::{debug, error, o, warn};
 use slot_clock::SlotClock;
 use types::{
-    Attestation, EthSpec, Slot, SubnetId, SyncCommitteeSubscription, SyncSubnetId,
+    AttestationData, EthSpec, Slot, SubnetId, SyncCommitteeSubscription, SyncSubnetId,
     ValidatorSubscription,
 };
 
@@ -363,7 +363,7 @@ impl<T: BeaconChainTypes> SubnetService<T> {
     pub fn should_process_attestation(
         &self,
         subnet: Subnet,
-        attestation: &Attestation<T::EthSpec>,
+        attestation_data: &AttestationData,
     ) -> bool {
         // Proposer-only mode does not need to process attestations
         if self.proposer_only {
@@ -374,7 +374,7 @@ impl<T: BeaconChainTypes> SubnetService<T> {
             .map(|tracked_vals| {
                 tracked_vals.contains_key(&ExactSubnet {
                     subnet,
-                    slot: attestation.data().slot,
+                    slot: attestation_data.slot,
                 })
             })
             .unwrap_or(true)
diff --git a/beacon_node/network/src/sync/backfill_sync/mod.rs b/beacon_node/network/src/sync/backfill_sync/mod.rs
index 5703ed3504..a3d2c82642 100644
--- a/beacon_node/network/src/sync/backfill_sync/mod.rs
+++ b/beacon_node/network/src/sync/backfill_sync/mod.rs
@@ -388,67 +388,59 @@ impl<T: BeaconChainTypes> BackFillSync<T> {
         blocks: Vec<RpcBlock<T::EthSpec>>,
     ) -> Result<ProcessResult, BackFillError> {
         // check if we have this batch
-        let batch = match self.batches.get_mut(&batch_id) {
-            None => {
-                if !matches!(self.state(), BackFillState::Failed) {
-                    // A batch might get removed when the chain advances, so this is non fatal.
-                    debug!(self.log, "Received a block for unknown batch"; "epoch" => batch_id);
-                }
-                return Ok(ProcessResult::Successful);
-            }
-            Some(batch) => {
-                // A batch could be retried without the peer failing the request (disconnecting/
-                // sending an error /timeout) if the peer is removed from the chain for other
-                // reasons. Check that this block belongs to the expected peer, and that the
-                // request_id matches
-                // TODO(das): removed peer_id matching as the node may request a different peer for data
-                // columns.
-                if !batch.is_expecting_block(&request_id) {
-                    return Ok(ProcessResult::Successful);
-                }
-                batch
+        let Some(batch) = self.batches.get_mut(&batch_id) else {
+            if !matches!(self.state(), BackFillState::Failed) {
+                // A batch might get removed when the chain advances, so this is non fatal.
+                debug!(self.log, "Received a block for unknown batch"; "epoch" => batch_id);
             }
+            return Ok(ProcessResult::Successful);
         };
 
-        {
-            // A stream termination has been sent. This batch has ended. Process a completed batch.
-            // Remove the request from the peer's active batches
-            self.active_requests
-                .get_mut(peer_id)
-                .map(|active_requests| active_requests.remove(&batch_id));
+        // A batch could be retried without the peer failing the request (disconnecting/
+        // sending an error /timeout) if the peer is removed from the chain for other
+        // reasons. Check that this block belongs to the expected peer, and that the
+        // request_id matches
+        // TODO(das): removed peer_id matching as the node may request a different peer for data
+        // columns.
+        if !batch.is_expecting_block(&request_id) {
+            return Ok(ProcessResult::Successful);
+        }
 
-            match batch.download_completed(blocks) {
-                Ok(received) => {
-                    let awaiting_batches =
-                        self.processing_target.saturating_sub(batch_id) / BACKFILL_EPOCHS_PER_BATCH;
-                    debug!(self.log, "Completed batch received"; "epoch" => batch_id, "blocks" => received, "awaiting_batches" => awaiting_batches);
+        // A stream termination has been sent. This batch has ended. Process a completed batch.
+        // Remove the request from the peer's active batches
+        self.active_requests
+            .get_mut(peer_id)
+            .map(|active_requests| active_requests.remove(&batch_id));
 
-                    // pre-emptively request more blocks from peers whilst we process current blocks,
-                    self.request_batches(network)?;
-                    self.process_completed_batches(network)
-                }
-                Err(result) => {
-                    let (expected_boundary, received_boundary, outcome) = match result {
-                        Err(e) => {
-                            return self
-                                .fail_sync(BackFillError::BatchInvalidState(batch_id, e.0))
-                                .map(|_| ProcessResult::Successful);
-                        }
-                        Ok(v) => v,
-                    };
-                    warn!(self.log, "Batch received out of range blocks"; "expected_boundary" => expected_boundary, "received_boundary" => received_boundary,
+        match batch.download_completed(blocks) {
+            Ok(received) => {
+                let awaiting_batches =
+                    self.processing_target.saturating_sub(batch_id) / BACKFILL_EPOCHS_PER_BATCH;
+                debug!(self.log, "Completed batch received"; "epoch" => batch_id, "blocks" => received, "awaiting_batches" => awaiting_batches);
+
+                // pre-emptively request more blocks from peers whilst we process current blocks,
+                self.request_batches(network)?;
+                self.process_completed_batches(network)
+            }
+            Err(result) => {
+                let (expected_boundary, received_boundary, outcome) = match result {
+                    Err(e) => {
+                        self.fail_sync(BackFillError::BatchInvalidState(batch_id, e.0))?;
+                        return Ok(ProcessResult::Successful);
+                    }
+                    Ok(v) => v,
+                };
+                warn!(self.log, "Batch received out of range blocks"; "expected_boundary" => expected_boundary, "received_boundary" => received_boundary,
                         "peer_id" => %peer_id, batch);
 
-                    if let BatchOperationOutcome::Failed { blacklist: _ } = outcome {
-                        error!(self.log, "Backfill failed"; "epoch" => batch_id, "received_boundary" => received_boundary, "expected_boundary" => expected_boundary);
-                        return self
-                            .fail_sync(BackFillError::BatchDownloadFailed(batch_id))
-                            .map(|_| ProcessResult::Successful);
-                    }
-                    // this batch can't be used, so we need to request it again.
-                    self.retry_batch_download(network, batch_id)
-                        .map(|_| ProcessResult::Successful)
+                if let BatchOperationOutcome::Failed { blacklist: _ } = outcome {
+                    error!(self.log, "Backfill failed"; "epoch" => batch_id, "received_boundary" => received_boundary, "expected_boundary" => expected_boundary);
+                    self.fail_sync(BackFillError::BatchDownloadFailed(batch_id))?;
+                    return Ok(ProcessResult::Successful);
                 }
+                // this batch can't be used, so we need to request it again.
+                self.retry_batch_download(network, batch_id)?;
+                Ok(ProcessResult::Successful)
             }
         }
     }
@@ -582,20 +574,16 @@ impl<T: BeaconChainTypes> BackFillSync<T> {
             }
         };
 
-        let peer = match batch.current_peer() {
-            Some(v) => *v,
-            None => {
-                return self
-                    .fail_sync(BackFillError::BatchInvalidState(
-                        batch_id,
-                        String::from("Peer does not exist"),
-                    ))
-                    .map(|_| ProcessResult::Successful)
-            }
+        let Some(peer) = batch.current_peer() else {
+            self.fail_sync(BackFillError::BatchInvalidState(
+                batch_id,
+                String::from("Peer does not exist"),
+            ))?;
+            return Ok(ProcessResult::Successful);
         };
 
         debug!(self.log, "Backfill batch processed"; "result" => ?result, &batch,
-            "batch_epoch" => batch_id, "peer" => %peer, "client" => %network.client_type(&peer));
+            "batch_epoch" => batch_id, "peer" => %peer, "client" => %network.client_type(peer));
 
         match result {
             BatchProcessResult::Success {
@@ -679,8 +667,8 @@ impl<T: BeaconChainTypes> BackFillSync<T> {
                 {
                     self.fail_sync(BackFillError::BatchInvalidState(batch_id, e.0))?;
                 }
-                self.retry_batch_download(network, batch_id)
-                    .map(|_| ProcessResult::Successful)
+                self.retry_batch_download(network, batch_id)?;
+                Ok(ProcessResult::Successful)
             }
         }
     }
@@ -712,11 +700,10 @@ impl<T: BeaconChainTypes> BackFillSync<T> {
                     // - AwaitingDownload -> A recoverable failed batch should have been
                     //   re-requested.
                     // - Processing -> `self.current_processing_batch` is None
-                    return self
-                        .fail_sync(BackFillError::InvalidSyncState(String::from(
-                            "Invalid expected batch state",
-                        )))
-                        .map(|_| ProcessResult::Successful);
+                    self.fail_sync(BackFillError::InvalidSyncState(String::from(
+                        "Invalid expected batch state",
+                    )))?;
+                    return Ok(ProcessResult::Successful);
                 }
                 BatchState::AwaitingValidation(_) => {
                     // TODO: I don't think this state is possible, log a CRIT just in case.
@@ -731,12 +718,11 @@ impl<T: BeaconChainTypes> BackFillSync<T> {
                 }
             }
         } else {
-            return self
-                .fail_sync(BackFillError::InvalidSyncState(format!(
-                    "Batch not found for current processing target {}",
-                    self.processing_target
-                )))
-                .map(|_| ProcessResult::Successful);
+            self.fail_sync(BackFillError::InvalidSyncState(format!(
+                "Batch not found for current processing target {}",
+                self.processing_target
+            )))?;
+            return Ok(ProcessResult::Successful);
         }
         Ok(ProcessResult::Successful)
     }
diff --git a/beacon_node/network/src/sync/block_lookups/common.rs b/beacon_node/network/src/sync/block_lookups/common.rs
index 5e336d9c38..8eefb2d675 100644
--- a/beacon_node/network/src/sync/block_lookups/common.rs
+++ b/beacon_node/network/src/sync/block_lookups/common.rs
@@ -9,6 +9,8 @@ use crate::sync::network_context::{LookupRequestResult, SyncNetworkContext};
 use beacon_chain::block_verification_types::RpcBlock;
 use beacon_chain::BeaconChainTypes;
 use lighthouse_network::service::api_types::Id;
+use parking_lot::RwLock;
+use std::collections::HashSet;
 use std::sync::Arc;
 use types::blob_sidecar::FixedBlobSidecarList;
 use types::{DataColumnSidecarList, SignedBeaconBlock};
@@ -41,7 +43,7 @@ pub trait RequestState<T: BeaconChainTypes> {
     fn make_request(
         &self,
         id: Id,
-        peer_id: PeerId,
+        lookup_peers: Arc<RwLock<HashSet<PeerId>>>,
         expected_blobs: usize,
         cx: &mut SyncNetworkContext<T>,
     ) -> Result<LookupRequestResult, LookupRequestError>;
@@ -76,11 +78,11 @@ impl<T: BeaconChainTypes> RequestState<T> for BlockRequestState<T::EthSpec> {
     fn make_request(
         &self,
         id: SingleLookupId,
-        peer_id: PeerId,
+        lookup_peers: Arc<RwLock<HashSet<PeerId>>>,
         _: usize,
         cx: &mut SyncNetworkContext<T>,
     ) -> Result<LookupRequestResult, LookupRequestError> {
-        cx.block_lookup_request(id, peer_id, self.requested_block_root)
+        cx.block_lookup_request(id, lookup_peers, self.requested_block_root)
             .map_err(LookupRequestError::SendFailedNetwork)
     }
 
@@ -124,11 +126,11 @@ impl<T: BeaconChainTypes> RequestState<T> for BlobRequestState<T::EthSpec> {
     fn make_request(
         &self,
         id: Id,
-        peer_id: PeerId,
+        lookup_peers: Arc<RwLock<HashSet<PeerId>>>,
         expected_blobs: usize,
         cx: &mut SyncNetworkContext<T>,
     ) -> Result<LookupRequestResult, LookupRequestError> {
-        cx.blob_lookup_request(id, peer_id, self.block_root, expected_blobs)
+        cx.blob_lookup_request(id, lookup_peers, self.block_root, expected_blobs)
             .map_err(LookupRequestError::SendFailedNetwork)
     }
 
@@ -172,12 +174,11 @@ impl<T: BeaconChainTypes> RequestState<T> for CustodyRequestState<T::EthSpec> {
     fn make_request(
         &self,
         id: Id,
-        // TODO(das): consider selecting peers that have custody but are in this set
-        _peer_id: PeerId,
+        lookup_peers: Arc<RwLock<HashSet<PeerId>>>,
         _: usize,
         cx: &mut SyncNetworkContext<T>,
     ) -> Result<LookupRequestResult, LookupRequestError> {
-        cx.custody_lookup_request(id, self.block_root)
+        cx.custody_lookup_request(id, self.block_root, lookup_peers)
             .map_err(LookupRequestError::SendFailedNetwork)
     }
 
diff --git a/beacon_node/network/src/sync/block_lookups/mod.rs b/beacon_node/network/src/sync/block_lookups/mod.rs
index 5a11bca481..ac4df42a4e 100644
--- a/beacon_node/network/src/sync/block_lookups/mod.rs
+++ b/beacon_node/network/src/sync/block_lookups/mod.rs
@@ -153,14 +153,7 @@ impl<T: BeaconChainTypes> BlockLookups<T> {
     pub(crate) fn active_single_lookups(&self) -> Vec<BlockLookupSummary> {
         self.single_block_lookups
             .iter()
-            .map(|(id, l)| {
-                (
-                    *id,
-                    l.block_root(),
-                    l.awaiting_parent(),
-                    l.all_peers().copied().collect(),
-                )
-            })
+            .map(|(id, l)| (*id, l.block_root(), l.awaiting_parent(), l.all_peers()))
             .collect()
     }
 
@@ -283,7 +276,7 @@ impl<T: BeaconChainTypes> BlockLookups<T> {
                         .find(|(_, l)| l.block_root() == parent_chain_tip)
                     {
                         cx.send_sync_message(SyncMessage::AddPeersForceRangeSync {
-                            peers: lookup.all_peers().copied().collect(),
+                            peers: lookup.all_peers(),
                             head_slot: tip_lookup.peek_downloaded_block_slot(),
                             head_root: parent_chain_tip,
                         });
@@ -682,7 +675,7 @@ impl<T: BeaconChainTypes> BlockLookups<T> {
                 lookup.continue_requests(cx)
             }
             Action::ParentUnknown { parent_root } => {
-                let peers = lookup.all_peers().copied().collect::<Vec<_>>();
+                let peers = lookup.all_peers();
                 lookup.set_awaiting_parent(parent_root);
                 debug!(self.log, "Marking lookup as awaiting parent"; "id" => lookup.id, "block_root" => ?block_root, "parent_root" => ?parent_root);
                 self.search_parent_of_child(parent_root, block_root, &peers, cx);
diff --git a/beacon_node/network/src/sync/block_lookups/single_block_lookup.rs b/beacon_node/network/src/sync/block_lookups/single_block_lookup.rs
index 9bbd2bf295..3789dbe91e 100644
--- a/beacon_node/network/src/sync/block_lookups/single_block_lookup.rs
+++ b/beacon_node/network/src/sync/block_lookups/single_block_lookup.rs
@@ -7,7 +7,7 @@ use crate::sync::network_context::{
 use beacon_chain::{BeaconChainTypes, BlockProcessStatus};
 use derivative::Derivative;
 use lighthouse_network::service::api_types::Id;
-use rand::seq::IteratorRandom;
+use parking_lot::RwLock;
 use std::collections::HashSet;
 use std::fmt::Debug;
 use std::sync::Arc;
@@ -33,8 +33,6 @@ pub enum LookupRequestError {
         /// The failed attempts were primarily due to processing failures.
         cannot_process: bool,
     },
-    /// No peers left to serve this lookup
-    NoPeers,
     /// Error sending event to network
     SendFailedNetwork(RpcRequestSendError),
     /// Error sending event to processor
@@ -63,9 +61,12 @@ pub struct SingleBlockLookup<T: BeaconChainTypes> {
     pub id: Id,
     pub block_request_state: BlockRequestState<T::EthSpec>,
     pub component_requests: ComponentRequests<T::EthSpec>,
-    /// Peers that claim to have imported this set of block components
+    /// Peers that claim to have imported this set of block components. This state is shared with
+    /// the custody request to have an updated view of the peers that claim to have imported the
+    /// block associated with this lookup. The peer set of a lookup can change rapidly, and faster
+    /// than the lifetime of a custody request.
     #[derivative(Debug(format_with = "fmt_peer_set_as_len"))]
-    peers: HashSet<PeerId>,
+    peers: Arc<RwLock<HashSet<PeerId>>>,
     block_root: Hash256,
     awaiting_parent: Option<Hash256>,
     created: Instant,
@@ -92,7 +93,7 @@ impl<T: BeaconChainTypes> SingleBlockLookup<T> {
             id,
             block_request_state: BlockRequestState::new(requested_block_root),
             component_requests: ComponentRequests::WaitingForBlock,
-            peers: HashSet::from_iter(peers.iter().copied()),
+            peers: Arc::new(RwLock::new(HashSet::from_iter(peers.iter().copied()))),
             block_root: requested_block_root,
             awaiting_parent,
             created: Instant::now(),
@@ -215,8 +216,7 @@ impl<T: BeaconChainTypes> SingleBlockLookup<T> {
                 let block_epoch = block.slot().epoch(T::EthSpec::slots_per_epoch());
                 if expected_blobs == 0 {
                     self.component_requests = ComponentRequests::NotNeeded("no data");
-                }
-                if cx.chain.should_fetch_blobs(block_epoch) {
+                } else if cx.chain.should_fetch_blobs(block_epoch) {
                     self.component_requests = ComponentRequests::ActiveBlobRequest(
                         BlobRequestState::new(self.block_root),
                         expected_blobs,
@@ -283,24 +283,11 @@ impl<T: BeaconChainTypes> SingleBlockLookup<T> {
                 return Err(LookupRequestError::TooManyAttempts { cannot_process });
             }
 
-            let Some(peer_id) = self.use_rand_available_peer() else {
-                // Allow lookup to not have any peers and do nothing. This is an optimization to not
-                // lose progress of lookups created from a block with unknown parent before we receive
-                // attestations for said block.
-                // Lookup sync event safety: If a lookup requires peers to make progress, and does
-                // not receive any new peers for some time it will be dropped. If it receives a new
-                // peer it must attempt to make progress.
-                R::request_state_mut(self)
-                    .map_err(|e| LookupRequestError::BadState(e.to_owned()))?
-                    .get_state_mut()
-                    .update_awaiting_download_status("no peers");
-                return Ok(());
-            };
-
+            let peers = self.peers.clone();
             let request = R::request_state_mut(self)
                 .map_err(|e| LookupRequestError::BadState(e.to_owned()))?;
 
-            match request.make_request(id, peer_id, expected_blobs, cx)? {
+            match request.make_request(id, peers, expected_blobs, cx)? {
                 LookupRequestResult::RequestSent(req_id) => {
                     // Lookup sync event safety: If make_request returns `RequestSent`, we are
                     // guaranteed that `BlockLookups::on_download_response` will be called exactly
@@ -348,29 +335,24 @@ impl<T: BeaconChainTypes> SingleBlockLookup<T> {
     }
 
     /// Get all unique peers that claim to have imported this set of block components
-    pub fn all_peers(&self) -> impl Iterator<Item = &PeerId> + '_ {
-        self.peers.iter()
+    pub fn all_peers(&self) -> Vec<PeerId> {
+        self.peers.read().iter().copied().collect()
     }
 
     /// Add peer to all request states. The peer must be able to serve this request.
     /// Returns true if the peer was newly inserted into some request state.
     pub fn add_peer(&mut self, peer_id: PeerId) -> bool {
-        self.peers.insert(peer_id)
+        self.peers.write().insert(peer_id)
     }
 
     /// Remove peer from available peers.
     pub fn remove_peer(&mut self, peer_id: &PeerId) {
-        self.peers.remove(peer_id);
+        self.peers.write().remove(peer_id);
     }
 
     /// Returns true if this lookup has zero peers
     pub fn has_no_peers(&self) -> bool {
-        self.peers.is_empty()
-    }
-
-    /// Selects a random peer from available peers if any
-    fn use_rand_available_peer(&mut self) -> Option<PeerId> {
-        self.peers.iter().choose(&mut rand::thread_rng()).copied()
+        self.peers.read().is_empty()
     }
 }
 
@@ -689,8 +671,8 @@ impl<T: Clone> std::fmt::Debug for State<T> {
 }
 
 fn fmt_peer_set_as_len(
-    peer_set: &HashSet<PeerId>,
+    peer_set: &Arc<RwLock<HashSet<PeerId>>>,
     f: &mut std::fmt::Formatter,
 ) -> Result<(), std::fmt::Error> {
-    write!(f, "{}", peer_set.len())
+    write!(f, "{}", peer_set.read().len())
 }
diff --git a/beacon_node/network/src/sync/block_sidecar_coupling.rs b/beacon_node/network/src/sync/block_sidecar_coupling.rs
index 966ce55fab..70a3fe4f5a 100644
--- a/beacon_node/network/src/sync/block_sidecar_coupling.rs
+++ b/beacon_node/network/src/sync/block_sidecar_coupling.rs
@@ -2,13 +2,13 @@ use beacon_chain::{
     block_verification_types::RpcBlock, data_column_verification::CustodyDataColumn, get_block_root,
 };
 use lighthouse_network::PeerId;
-use ssz_types::VariableList;
 use std::{
     collections::{HashMap, VecDeque},
     sync::Arc,
 };
 use types::{
-    BlobSidecar, ChainSpec, ColumnIndex, DataColumnSidecar, EthSpec, Hash256, SignedBeaconBlock,
+    BlobSidecar, ChainSpec, ColumnIndex, DataColumnSidecar, EthSpec, Hash256, RuntimeVariableList,
+    SignedBeaconBlock,
 };
 
 #[derive(Debug)]
@@ -31,6 +31,7 @@ pub struct RangeBlockComponentsRequest<E: EthSpec> {
     num_custody_column_requests: Option<usize>,
     /// The peers the request was made to.
     pub(crate) peer_ids: Vec<PeerId>,
+    max_blobs_per_block: usize,
 }
 
 impl<E: EthSpec> RangeBlockComponentsRequest<E> {
@@ -39,6 +40,7 @@ impl<E: EthSpec> RangeBlockComponentsRequest<E> {
         expects_custody_columns: Option<Vec<ColumnIndex>>,
         num_custody_column_requests: Option<usize>,
         peer_ids: Vec<PeerId>,
+        max_blobs_per_block: usize,
     ) -> Self {
         Self {
             blocks: <_>::default(),
@@ -51,6 +53,7 @@ impl<E: EthSpec> RangeBlockComponentsRequest<E> {
             expects_custody_columns,
             num_custody_column_requests,
             peer_ids,
+            max_blobs_per_block,
         }
     }
 
@@ -100,7 +103,7 @@ impl<E: EthSpec> RangeBlockComponentsRequest<E> {
         let mut responses = Vec::with_capacity(blocks.len());
         let mut blob_iter = blobs.into_iter().peekable();
         for block in blocks.into_iter() {
-            let mut blob_list = Vec::with_capacity(E::max_blobs_per_block());
+            let mut blob_list = Vec::with_capacity(self.max_blobs_per_block);
             while {
                 let pair_next_blob = blob_iter
                     .peek()
@@ -111,7 +114,7 @@ impl<E: EthSpec> RangeBlockComponentsRequest<E> {
                 blob_list.push(blob_iter.next().ok_or("Missing next blob".to_string())?);
             }
 
-            let mut blobs_buffer = vec![None; E::max_blobs_per_block()];
+            let mut blobs_buffer = vec![None; self.max_blobs_per_block];
             for blob in blob_list {
                 let blob_index = blob.index as usize;
                 let Some(blob_opt) = blobs_buffer.get_mut(blob_index) else {
@@ -123,7 +126,11 @@ impl<E: EthSpec> RangeBlockComponentsRequest<E> {
                     *blob_opt = Some(blob);
                 }
             }
-            let blobs = VariableList::from(blobs_buffer.into_iter().flatten().collect::<Vec<_>>());
+            let blobs = RuntimeVariableList::new(
+                blobs_buffer.into_iter().flatten().collect::<Vec<_>>(),
+                self.max_blobs_per_block,
+            )
+            .map_err(|_| "Blobs returned exceeds max length".to_string())?;
             responses.push(RpcBlock::new(None, block, Some(blobs)).map_err(|e| format!("{e:?}"))?)
         }
 
@@ -245,12 +252,18 @@ mod tests {
 
     #[test]
     fn no_blobs_into_responses() {
+        let spec = test_spec::<E>();
         let peer_id = PeerId::random();
-        let mut info = RangeBlockComponentsRequest::<E>::new(false, None, None, vec![peer_id]);
         let mut rng = XorShiftRng::from_seed([42; 16]);
         let blocks = (0..4)
-            .map(|_| generate_rand_block_and_blobs::<E>(ForkName::Base, NumBlobs::None, &mut rng).0)
+            .map(|_| {
+                generate_rand_block_and_blobs::<E>(ForkName::Base, NumBlobs::None, &mut rng, &spec)
+                    .0
+            })
             .collect::<Vec<_>>();
+        let max_len = spec.max_blobs_per_block(blocks.first().unwrap().epoch()) as usize;
+        let mut info =
+            RangeBlockComponentsRequest::<E>::new(false, None, None, vec![peer_id], max_len);
 
         // Send blocks and complete terminate response
         for block in blocks {
@@ -265,15 +278,24 @@ mod tests {
 
     #[test]
     fn empty_blobs_into_responses() {
+        let spec = test_spec::<E>();
         let peer_id = PeerId::random();
-        let mut info = RangeBlockComponentsRequest::<E>::new(true, None, None, vec![peer_id]);
         let mut rng = XorShiftRng::from_seed([42; 16]);
         let blocks = (0..4)
             .map(|_| {
                 // Always generate some blobs.
-                generate_rand_block_and_blobs::<E>(ForkName::Deneb, NumBlobs::Number(3), &mut rng).0
+                generate_rand_block_and_blobs::<E>(
+                    ForkName::Deneb,
+                    NumBlobs::Number(3),
+                    &mut rng,
+                    &spec,
+                )
+                .0
             })
             .collect::<Vec<_>>();
+        let max_len = spec.max_blobs_per_block(blocks.first().unwrap().epoch()) as usize;
+        let mut info =
+            RangeBlockComponentsRequest::<E>::new(true, None, None, vec![peer_id], max_len);
 
         // Send blocks and complete terminate response
         for block in blocks {
@@ -294,24 +316,26 @@ mod tests {
     fn rpc_block_with_custody_columns() {
         let spec = test_spec::<E>();
         let expects_custody_columns = vec![1, 2, 3, 4];
-        let mut info = RangeBlockComponentsRequest::<E>::new(
-            false,
-            Some(expects_custody_columns.clone()),
-            Some(expects_custody_columns.len()),
-            vec![PeerId::random()],
-        );
+
         let mut rng = XorShiftRng::from_seed([42; 16]);
         let blocks = (0..4)
             .map(|_| {
                 generate_rand_block_and_data_columns::<E>(
-                    ForkName::Deneb,
+                    ForkName::Fulu,
                     NumBlobs::Number(1),
                     &mut rng,
                     &spec,
                 )
             })
             .collect::<Vec<_>>();
-
+        let max_len = spec.max_blobs_per_block(blocks.first().unwrap().0.epoch()) as usize;
+        let mut info = RangeBlockComponentsRequest::<E>::new(
+            false,
+            Some(expects_custody_columns.clone()),
+            Some(expects_custody_columns.len()),
+            vec![PeerId::random()],
+            max_len,
+        );
         // Send blocks and complete terminate response
         for block in &blocks {
             info.add_block_response(Some(block.0.clone().into()));
@@ -355,24 +379,26 @@ mod tests {
         let spec = test_spec::<E>();
         let expects_custody_columns = vec![1, 2, 3, 4];
         let num_of_data_column_requests = 2;
-        let mut info = RangeBlockComponentsRequest::<E>::new(
-            false,
-            Some(expects_custody_columns.clone()),
-            Some(num_of_data_column_requests),
-            vec![PeerId::random()],
-        );
+
         let mut rng = XorShiftRng::from_seed([42; 16]);
         let blocks = (0..4)
             .map(|_| {
                 generate_rand_block_and_data_columns::<E>(
-                    ForkName::Deneb,
+                    ForkName::Fulu,
                     NumBlobs::Number(1),
                     &mut rng,
                     &spec,
                 )
             })
             .collect::<Vec<_>>();
-
+        let max_len = spec.max_blobs_per_block(blocks.first().unwrap().0.epoch()) as usize;
+        let mut info = RangeBlockComponentsRequest::<E>::new(
+            false,
+            Some(expects_custody_columns.clone()),
+            Some(num_of_data_column_requests),
+            vec![PeerId::random()],
+            max_len,
+        );
         // Send blocks and complete terminate response
         for block in &blocks {
             info.add_block_response(Some(block.0.clone().into()));
diff --git a/beacon_node/network/src/sync/manager.rs b/beacon_node/network/src/sync/manager.rs
index 5d02be2b4c..fd91dc78b1 100644
--- a/beacon_node/network/src/sync/manager.rs
+++ b/beacon_node/network/src/sync/manager.rs
@@ -69,7 +69,9 @@ use std::ops::Sub;
 use std::sync::Arc;
 use std::time::Duration;
 use tokio::sync::mpsc;
-use types::{BlobSidecar, DataColumnSidecar, EthSpec, Hash256, SignedBeaconBlock, Slot};
+use types::{
+    BlobSidecar, DataColumnSidecar, EthSpec, ForkContext, Hash256, SignedBeaconBlock, Slot,
+};
 
 #[cfg(test)]
 use types::ColumnIndex;
@@ -258,10 +260,11 @@ pub fn spawn<T: BeaconChainTypes>(
     network_send: mpsc::UnboundedSender<NetworkMessage<T::EthSpec>>,
     beacon_processor: Arc<NetworkBeaconProcessor<T>>,
     sync_recv: mpsc::UnboundedReceiver<SyncMessage<T::EthSpec>>,
+    fork_context: Arc<ForkContext>,
     log: slog::Logger,
 ) {
     assert!(
-        beacon_chain.spec.max_request_blocks >= T::EthSpec::slots_per_epoch() * EPOCHS_PER_BATCH,
+        beacon_chain.spec.max_request_blocks(fork_context.current_fork()) as u64 >= T::EthSpec::slots_per_epoch() * EPOCHS_PER_BATCH,
         "Max blocks that can be requested in a single batch greater than max allowed blocks in a single request"
     );
 
@@ -272,6 +275,7 @@ pub fn spawn<T: BeaconChainTypes>(
         beacon_processor,
         sync_recv,
         SamplingConfig::Default,
+        fork_context,
         log.clone(),
     );
 
@@ -287,6 +291,7 @@ impl<T: BeaconChainTypes> SyncManager<T> {
         beacon_processor: Arc<NetworkBeaconProcessor<T>>,
         sync_recv: mpsc::UnboundedReceiver<SyncMessage<T::EthSpec>>,
         sampling_config: SamplingConfig,
+        fork_context: Arc<ForkContext>,
         log: slog::Logger,
     ) -> Self {
         let network_globals = beacon_processor.network_globals.clone();
@@ -297,6 +302,7 @@ impl<T: BeaconChainTypes> SyncManager<T> {
                 network_send,
                 beacon_processor.clone(),
                 beacon_chain.clone(),
+                fork_context.clone(),
                 log.clone(),
             ),
             range_sync: RangeSync::new(
@@ -1234,6 +1240,7 @@ impl<T: BeaconChainTypes> SyncManager<T> {
             .network
             .range_block_and_blob_response(id, block_or_blob)
         {
+            let epoch = resp.sender_id.batch_id();
             match resp.responses {
                 Ok(blocks) => {
                     match resp.sender_id {
@@ -1277,6 +1284,7 @@ impl<T: BeaconChainTypes> SyncManager<T> {
                             resp.expects_custody_columns,
                             None,
                             vec![],
+                            self.chain.spec.max_blobs_per_block(epoch) as usize,
                         ),
                     );
                     // inform range that the request needs to be treated as failed
diff --git a/beacon_node/network/src/sync/network_context.rs b/beacon_node/network/src/sync/network_context.rs
index b6b7b315f3..4135f901b1 100644
--- a/beacon_node/network/src/sync/network_context.rs
+++ b/beacon_node/network/src/sync/network_context.rs
@@ -27,7 +27,8 @@ use lighthouse_network::service::api_types::{
     DataColumnsByRootRequester, Id, SingleLookupReqId, SyncRequestId,
 };
 use lighthouse_network::{Client, NetworkGlobals, PeerAction, PeerId, ReportSource};
-use rand::seq::SliceRandom;
+use parking_lot::RwLock;
+use rand::prelude::IteratorRandom;
 use rand::thread_rng;
 pub use requests::LookupVerifyError;
 use requests::{
@@ -36,14 +37,14 @@ use requests::{
 };
 use slog::{debug, error, warn};
 use std::collections::hash_map::Entry;
-use std::collections::HashMap;
+use std::collections::{HashMap, HashSet};
 use std::sync::Arc;
 use std::time::Duration;
 use tokio::sync::mpsc;
 use types::blob_sidecar::FixedBlobSidecarList;
 use types::{
-    BlobSidecar, ColumnIndex, DataColumnSidecar, DataColumnSidecarList, EthSpec, Hash256,
-    SignedBeaconBlock, Slot,
+    BlobSidecar, ColumnIndex, DataColumnSidecar, DataColumnSidecarList, EthSpec, ForkContext,
+    Hash256, SignedBeaconBlock, Slot,
 };
 
 pub mod custody;
@@ -67,6 +68,15 @@ pub enum RangeRequestId {
     },
 }
 
+impl RangeRequestId {
+    pub fn batch_id(&self) -> BatchId {
+        match self {
+            RangeRequestId::RangeSync { batch_id, .. } => *batch_id,
+            RangeRequestId::BackfillSync { batch_id, .. } => *batch_id,
+        }
+    }
+}
+
 #[derive(Debug)]
 pub enum RpcEvent<T> {
     StreamTermination,
@@ -206,6 +216,8 @@ pub struct SyncNetworkContext<T: BeaconChainTypes> {
 
     pub chain: Arc<BeaconChain<T>>,
 
+    fork_context: Arc<ForkContext>,
+
     /// Logger for the `SyncNetworkContext`.
     pub log: slog::Logger,
 }
@@ -234,6 +246,7 @@ impl<T: BeaconChainTypes> SyncNetworkContext<T> {
         network_send: mpsc::UnboundedSender<NetworkMessage<T::EthSpec>>,
         network_beacon_processor: Arc<NetworkBeaconProcessor<T>>,
         chain: Arc<BeaconChain<T>>,
+        fork_context: Arc<ForkContext>,
         log: slog::Logger,
     ) -> Self {
         SyncNetworkContext {
@@ -247,6 +260,7 @@ impl<T: BeaconChainTypes> SyncNetworkContext<T> {
             range_block_components_requests: FnvHashMap::default(),
             network_beacon_processor,
             chain,
+            fork_context,
             log,
         }
     }
@@ -299,8 +313,8 @@ impl<T: BeaconChainTypes> SyncNetworkContext<T> {
 
     pub fn get_random_custodial_peer(&self, column_index: ColumnIndex) -> Option<PeerId> {
         self.get_custodial_peers(column_index)
+            .into_iter()
             .choose(&mut thread_rng())
-            .cloned()
     }
 
     pub fn network_globals(&self) -> &NetworkGlobals<T::EthSpec> {
@@ -359,6 +373,7 @@ impl<T: BeaconChainTypes> SyncNetworkContext<T> {
             "count" => request.count(),
             "epoch" => epoch,
             "peer" => %peer_id,
+            "id" => id,
         );
         let rpc_request = match request {
             BlocksByRangeRequest::V1(ref req) => {
@@ -428,6 +443,7 @@ impl<T: BeaconChainTypes> SyncNetworkContext<T> {
                         "epoch" => epoch,
                         "columns" => ?columns_by_range_request.columns,
                         "peer" => %peer_id,
+                        "id" => id,
                     );
 
                     self.send_network_msg(NetworkMessage::SendRequest {
@@ -445,11 +461,13 @@ impl<T: BeaconChainTypes> SyncNetworkContext<T> {
                 (None, None)
             };
 
+        let max_blobs_len = self.chain.spec.max_blobs_per_block(epoch);
         let info = RangeBlockComponentsRequest::new(
             expected_blobs,
-            expects_columns,
+            expects_columns.map(|c| c.into_iter().collect()),
             num_of_column_req,
             requested_peers,
+            max_blobs_len as usize,
         );
         self.range_block_components_requests
             .insert(id, (sender_id, info));
@@ -459,7 +477,7 @@ impl<T: BeaconChainTypes> SyncNetworkContext<T> {
     fn make_columns_by_range_requests(
         &self,
         request: BlocksByRangeRequest,
-        custody_indexes: &Vec<ColumnIndex>,
+        custody_indexes: &HashSet<ColumnIndex>,
     ) -> Result<HashMap<PeerId, DataColumnsByRangeRequest>, RpcRequestSendError> {
         let mut peer_id_to_request_map = HashMap::new();
 
@@ -550,9 +568,24 @@ impl<T: BeaconChainTypes> SyncNetworkContext<T> {
     pub fn block_lookup_request(
         &mut self,
         lookup_id: SingleLookupId,
-        peer_id: PeerId,
+        lookup_peers: Arc<RwLock<HashSet<PeerId>>>,
         block_root: Hash256,
     ) -> Result<LookupRequestResult, RpcRequestSendError> {
+        let Some(peer_id) = lookup_peers
+            .read()
+            .iter()
+            .choose(&mut rand::thread_rng())
+            .copied()
+        else {
+            // Allow lookup to not have any peers and do nothing. This is an optimization to not
+            // lose progress of lookups created from a block with unknown parent before we receive
+            // attestations for said block.
+            // Lookup sync event safety: If a lookup requires peers to make progress, and does
+            // not receive any new peers for some time it will be dropped. If it receives a new
+            // peer it must attempt to make progress.
+            return Ok(LookupRequestResult::Pending("no peers"));
+        };
+
         match self.chain.get_block_process_status(&block_root) {
             // Unknown block, continue request to download
             BlockProcessStatus::Unknown => {}
@@ -596,7 +629,7 @@ impl<T: BeaconChainTypes> SyncNetworkContext<T> {
         self.network_send
             .send(NetworkMessage::SendRequest {
                 peer_id,
-                request: RequestType::BlocksByRoot(request.into_request(&self.chain.spec)),
+                request: RequestType::BlocksByRoot(request.into_request(&self.fork_context)),
                 request_id: AppRequestId::Sync(SyncRequestId::SingleBlock { id }),
             })
             .map_err(|_| RpcRequestSendError::NetworkSendError)?;
@@ -622,10 +655,25 @@ impl<T: BeaconChainTypes> SyncNetworkContext<T> {
     pub fn blob_lookup_request(
         &mut self,
         lookup_id: SingleLookupId,
-        peer_id: PeerId,
+        lookup_peers: Arc<RwLock<HashSet<PeerId>>>,
         block_root: Hash256,
         expected_blobs: usize,
     ) -> Result<LookupRequestResult, RpcRequestSendError> {
+        let Some(peer_id) = lookup_peers
+            .read()
+            .iter()
+            .choose(&mut rand::thread_rng())
+            .copied()
+        else {
+            // Allow lookup to not have any peers and do nothing. This is an optimization to not
+            // lose progress of lookups created from a block with unknown parent before we receive
+            // attestations for said block.
+            // Lookup sync event safety: If a lookup requires peers to make progress, and does
+            // not receive any new peers for some time it will be dropped. If it receives a new
+            // peer it must attempt to make progress.
+            return Ok(LookupRequestResult::Pending("no peers"));
+        };
+
         let imported_blob_indexes = self
             .chain
             .data_availability_checker
@@ -663,7 +711,7 @@ impl<T: BeaconChainTypes> SyncNetworkContext<T> {
         self.network_send
             .send(NetworkMessage::SendRequest {
                 peer_id,
-                request: RequestType::BlobsByRoot(request.clone().into_request(&self.chain.spec)),
+                request: RequestType::BlobsByRoot(request.clone().into_request(&self.fork_context)),
                 request_id: AppRequestId::Sync(SyncRequestId::SingleBlob { id }),
             })
             .map_err(|_| RpcRequestSendError::NetworkSendError)?;
@@ -728,6 +776,7 @@ impl<T: BeaconChainTypes> SyncNetworkContext<T> {
         &mut self,
         lookup_id: SingleLookupId,
         block_root: Hash256,
+        lookup_peers: Arc<RwLock<HashSet<PeerId>>>,
     ) -> Result<LookupRequestResult, RpcRequestSendError> {
         let custody_indexes_imported = self
             .chain
@@ -765,6 +814,7 @@ impl<T: BeaconChainTypes> SyncNetworkContext<T> {
             block_root,
             CustodyId { requester },
             &custody_indexes_to_fetch,
+            lookup_peers,
             self.log.clone(),
         );
 
@@ -950,12 +1000,23 @@ impl<T: BeaconChainTypes> SyncNetworkContext<T> {
     ) -> Option<RpcResponseResult<FixedBlobSidecarList<T::EthSpec>>> {
         let response = self.blobs_by_root_requests.on_response(id, rpc_event);
         let response = response.map(|res| {
-            res.and_then(
-                |(blobs, seen_timestamp)| match to_fixed_blob_sidecar_list(blobs) {
-                    Ok(blobs) => Ok((blobs, seen_timestamp)),
-                    Err(e) => Err(e.into()),
-                },
-            )
+            res.and_then(|(blobs, seen_timestamp)| {
+                if let Some(max_len) = blobs
+                    .first()
+                    .map(|blob| self.chain.spec.max_blobs_per_block(blob.epoch()) as usize)
+                {
+                    match to_fixed_blob_sidecar_list(blobs, max_len) {
+                        Ok(blobs) => Ok((blobs, seen_timestamp)),
+                        Err(e) => Err(e.into()),
+                    }
+                } else {
+                    Err(RpcResponseError::VerifyError(
+                        LookupVerifyError::InternalError(
+                            "Requested blobs for a block that has no blobs".to_string(),
+                        ),
+                    ))
+                }
+            })
         });
         if let Some(Err(RpcResponseError::VerifyError(e))) = &response {
             self.report_peer(peer_id, PeerAction::LowToleranceError, e.into());
@@ -1150,8 +1211,9 @@ impl<T: BeaconChainTypes> SyncNetworkContext<T> {
 
 fn to_fixed_blob_sidecar_list<E: EthSpec>(
     blobs: Vec<Arc<BlobSidecar<E>>>,
+    max_len: usize,
 ) -> Result<FixedBlobSidecarList<E>, LookupVerifyError> {
-    let mut fixed_list = FixedBlobSidecarList::default();
+    let mut fixed_list = FixedBlobSidecarList::new(vec![None; max_len]);
     for blob in blobs.into_iter() {
         let index = blob.index as usize;
         *fixed_list
diff --git a/beacon_node/network/src/sync/network_context/custody.rs b/beacon_node/network/src/sync/network_context/custody.rs
index e4bce3dafc..8a29545c21 100644
--- a/beacon_node/network/src/sync/network_context/custody.rs
+++ b/beacon_node/network/src/sync/network_context/custody.rs
@@ -7,8 +7,10 @@ use fnv::FnvHashMap;
 use lighthouse_network::service::api_types::{CustodyId, DataColumnsByRootRequester};
 use lighthouse_network::PeerId;
 use lru_cache::LRUTimeCache;
+use parking_lot::RwLock;
 use rand::Rng;
 use slog::{debug, warn};
+use std::collections::HashSet;
 use std::time::{Duration, Instant};
 use std::{collections::HashMap, marker::PhantomData, sync::Arc};
 use types::EthSpec;
@@ -32,6 +34,8 @@ pub struct ActiveCustodyRequest<T: BeaconChainTypes> {
     /// Peers that have recently failed to successfully respond to a columns by root request.
     /// Having a LRUTimeCache allows this request to not have to track disconnecting peers.
     failed_peers: LRUTimeCache<PeerId>,
+    /// Set of peers that claim to have imported this block and their custody columns
+    lookup_peers: Arc<RwLock<HashSet<PeerId>>>,
     /// Logger for the `SyncNetworkContext`.
     pub log: slog::Logger,
     _phantom: PhantomData<T>,
@@ -64,6 +68,7 @@ impl<T: BeaconChainTypes> ActiveCustodyRequest<T> {
         block_root: Hash256,
         custody_id: CustodyId,
         column_indices: &[ColumnIndex],
+        lookup_peers: Arc<RwLock<HashSet<PeerId>>>,
         log: slog::Logger,
     ) -> Self {
         Self {
@@ -76,6 +81,7 @@ impl<T: BeaconChainTypes> ActiveCustodyRequest<T> {
             ),
             active_batch_columns_requests: <_>::default(),
             failed_peers: LRUTimeCache::new(Duration::from_secs(FAILED_PEERS_CACHE_EXPIRY_SECONDS)),
+            lookup_peers,
             log,
             _phantom: PhantomData,
         }
@@ -215,6 +221,7 @@ impl<T: BeaconChainTypes> ActiveCustodyRequest<T> {
         }
 
         let mut columns_to_request_by_peer = HashMap::<PeerId, Vec<ColumnIndex>>::new();
+        let lookup_peers = self.lookup_peers.read();
 
         // Need to:
         // - track how many active requests a peer has for load balancing
@@ -244,6 +251,8 @@ impl<T: BeaconChainTypes> ActiveCustodyRequest<T> {
                     .iter()
                     .map(|peer| {
                         (
+                            // Prioritize peers that claim to know have imported this block
+                            if lookup_peers.contains(peer) { 0 } else { 1 },
                             // De-prioritize peers that have failed to successfully respond to
                             // requests recently
                             self.failed_peers.contains(peer),
@@ -257,7 +266,7 @@ impl<T: BeaconChainTypes> ActiveCustodyRequest<T> {
                     .collect::<Vec<_>>();
                 priorized_peers.sort_unstable();
 
-                if let Some((_, _, _, peer_id)) = priorized_peers.first() {
+                if let Some((_, _, _, _, peer_id)) = priorized_peers.first() {
                     columns_to_request_by_peer
                         .entry(*peer_id)
                         .or_default()
@@ -283,10 +292,11 @@ impl<T: BeaconChainTypes> ActiveCustodyRequest<T> {
                         block_root: self.block_root,
                         indices: indices.clone(),
                     },
-                    // true = enforce max_requests are returned data_columns_by_root. We only issue requests
-                    // for blocks after we know the block has data, and only request peers after they claim to
-                    // have imported the block+columns and claim to be custodians
-                    true,
+                    // If peer is in the lookup peer set, it claims to have imported the block and
+                    // must have its columns in custody. In that case, set `true = enforce max_requests`
+                    // and downscore if data_columns_by_root does not returned the expected custody
+                    // columns. For the rest of peers, don't downscore if columns are missing.
+                    lookup_peers.contains(&peer_id),
                 )
                 .map_err(Error::SendFailed)?;
 
diff --git a/beacon_node/network/src/sync/network_context/requests.rs b/beacon_node/network/src/sync/network_context/requests.rs
index b9214bafcd..4a5a16459d 100644
--- a/beacon_node/network/src/sync/network_context/requests.rs
+++ b/beacon_node/network/src/sync/network_context/requests.rs
@@ -28,6 +28,7 @@ pub enum LookupVerifyError {
     UnrequestedIndex(u64),
     InvalidInclusionProof,
     DuplicateData,
+    InternalError(String),
 }
 
 /// Collection of active requests of a single ReqResp method, i.e. `blocks_by_root`
diff --git a/beacon_node/network/src/sync/network_context/requests/blobs_by_root.rs b/beacon_node/network/src/sync/network_context/requests/blobs_by_root.rs
index fefb27a5ef..a670229884 100644
--- a/beacon_node/network/src/sync/network_context/requests/blobs_by_root.rs
+++ b/beacon_node/network/src/sync/network_context/requests/blobs_by_root.rs
@@ -1,6 +1,6 @@
 use lighthouse_network::rpc::methods::BlobsByRootRequest;
 use std::sync::Arc;
-use types::{blob_sidecar::BlobIdentifier, BlobSidecar, ChainSpec, EthSpec, Hash256};
+use types::{blob_sidecar::BlobIdentifier, BlobSidecar, EthSpec, ForkContext, Hash256};
 
 use super::{ActiveRequestItems, LookupVerifyError};
 
@@ -11,7 +11,7 @@ pub struct BlobsByRootSingleBlockRequest {
 }
 
 impl BlobsByRootSingleBlockRequest {
-    pub fn into_request(self, spec: &ChainSpec) -> BlobsByRootRequest {
+    pub fn into_request(self, spec: &ForkContext) -> BlobsByRootRequest {
         BlobsByRootRequest::new(
             self.indices
                 .into_iter()
diff --git a/beacon_node/network/src/sync/network_context/requests/blocks_by_root.rs b/beacon_node/network/src/sync/network_context/requests/blocks_by_root.rs
index f3cdcbe714..6d7eabf909 100644
--- a/beacon_node/network/src/sync/network_context/requests/blocks_by_root.rs
+++ b/beacon_node/network/src/sync/network_context/requests/blocks_by_root.rs
@@ -1,7 +1,7 @@
 use beacon_chain::get_block_root;
 use lighthouse_network::rpc::BlocksByRootRequest;
 use std::sync::Arc;
-use types::{ChainSpec, EthSpec, Hash256, SignedBeaconBlock};
+use types::{EthSpec, ForkContext, Hash256, SignedBeaconBlock};
 
 use super::{ActiveRequestItems, LookupVerifyError};
 
@@ -9,8 +9,8 @@ use super::{ActiveRequestItems, LookupVerifyError};
 pub struct BlocksByRootSingleRequest(pub Hash256);
 
 impl BlocksByRootSingleRequest {
-    pub fn into_request(self, spec: &ChainSpec) -> BlocksByRootRequest {
-        BlocksByRootRequest::new(vec![self.0], spec)
+    pub fn into_request(self, fork_context: &ForkContext) -> BlocksByRootRequest {
+        BlocksByRootRequest::new(vec![self.0], fork_context)
     }
 }
 
diff --git a/beacon_node/network/src/sync/peer_sync_info.rs b/beacon_node/network/src/sync/peer_sync_info.rs
index c01366f1be..5ea1533d35 100644
--- a/beacon_node/network/src/sync/peer_sync_info.rs
+++ b/beacon_node/network/src/sync/peer_sync_info.rs
@@ -30,8 +30,8 @@ pub fn remote_sync_type<T: BeaconChainTypes>(
 ) -> PeerSyncType {
     // auxiliary variables for clarity: Inclusive boundaries of the range in which we consider a peer's
     // head "near" ours.
-    let near_range_start = local.head_slot - SLOT_IMPORT_TOLERANCE as u64;
-    let near_range_end = local.head_slot + SLOT_IMPORT_TOLERANCE as u64;
+    let near_range_start = local.head_slot.saturating_sub(SLOT_IMPORT_TOLERANCE);
+    let near_range_end = local.head_slot.saturating_add(SLOT_IMPORT_TOLERANCE);
 
     match remote.finalized_epoch.cmp(&local.finalized_epoch) {
         Ordering::Less => {
diff --git a/beacon_node/network/src/sync/range_sync/chain.rs b/beacon_node/network/src/sync/range_sync/chain.rs
index 51d9d9da37..4eb73f5483 100644
--- a/beacon_node/network/src/sync/range_sync/chain.rs
+++ b/beacon_node/network/src/sync/range_sync/chain.rs
@@ -15,7 +15,6 @@ use rand::seq::SliceRandom;
 use rand::Rng;
 use slog::{crit, debug, o, warn};
 use std::collections::{btree_map::Entry, BTreeMap, HashSet};
-use std::hash::{Hash, Hasher};
 use strum::IntoStaticStr;
 use types::{Epoch, EthSpec, Hash256, Slot};
 
@@ -56,7 +55,7 @@ pub enum RemoveChain {
 pub struct KeepChain;
 
 /// A chain identifier
-pub type ChainId = u64;
+pub type ChainId = Id;
 pub type BatchId = Epoch;
 
 #[derive(Debug, Copy, Clone, IntoStaticStr)]
@@ -127,14 +126,9 @@ pub enum ChainSyncingState {
 }
 
 impl<T: BeaconChainTypes> SyncingChain<T> {
-    pub fn id(target_root: &Hash256, target_slot: &Slot) -> u64 {
-        let mut hasher = std::collections::hash_map::DefaultHasher::new();
-        (target_root, target_slot).hash(&mut hasher);
-        hasher.finish()
-    }
-
     #[allow(clippy::too_many_arguments)]
     pub fn new(
+        id: Id,
         start_epoch: Epoch,
         target_head_slot: Slot,
         target_head_root: Hash256,
@@ -145,8 +139,6 @@ impl<T: BeaconChainTypes> SyncingChain<T> {
         let mut peers = FnvHashMap::default();
         peers.insert(peer_id, Default::default());
 
-        let id = SyncingChain::<T>::id(&target_head_root, &target_head_slot);
-
         SyncingChain {
             id,
             chain_type,
@@ -165,6 +157,11 @@ impl<T: BeaconChainTypes> SyncingChain<T> {
         }
     }
 
+    /// Returns true if this chain has the same target
+    pub fn has_same_target(&self, target_head_slot: Slot, target_head_root: Hash256) -> bool {
+        self.target_head_slot == target_head_slot && self.target_head_root == target_head_root
+    }
+
     /// Check if the chain has peers from which to process batches.
     pub fn available_peers(&self) -> usize {
         self.peers.len()
@@ -1258,7 +1255,7 @@ impl<T: BeaconChainTypes> slog::KV for SyncingChain<T> {
         serializer: &mut dyn slog::Serializer,
     ) -> slog::Result {
         use slog::Value;
-        serializer.emit_u64("id", self.id)?;
+        serializer.emit_u32("id", self.id)?;
         Value::serialize(&self.start_epoch, record, "from", serializer)?;
         Value::serialize(
             &self.target_head_slot.epoch(T::EthSpec::slots_per_epoch()),
diff --git a/beacon_node/network/src/sync/range_sync/chain_collection.rs b/beacon_node/network/src/sync/range_sync/chain_collection.rs
index c030d0a19e..15bdf85e20 100644
--- a/beacon_node/network/src/sync/range_sync/chain_collection.rs
+++ b/beacon_node/network/src/sync/range_sync/chain_collection.rs
@@ -9,6 +9,7 @@ use crate::metrics;
 use crate::sync::network_context::SyncNetworkContext;
 use beacon_chain::{BeaconChain, BeaconChainTypes};
 use fnv::FnvHashMap;
+use lighthouse_network::service::api_types::Id;
 use lighthouse_network::PeerId;
 use lighthouse_network::SyncInfo;
 use slog::{crit, debug, error};
@@ -29,9 +30,9 @@ const MIN_FINALIZED_CHAIN_PROCESSED_EPOCHS: u64 = 10;
 #[derive(Clone)]
 pub enum RangeSyncState {
     /// A finalized chain is being synced.
-    Finalized(u64),
+    Finalized(Id),
     /// There are no finalized chains and we are syncing one more head chains.
-    Head(SmallVec<[u64; PARALLEL_HEAD_CHAINS]>),
+    Head(SmallVec<[Id; PARALLEL_HEAD_CHAINS]>),
     /// There are no head or finalized chains and no long range sync is in progress.
     Idle,
 }
@@ -74,7 +75,7 @@ impl<T: BeaconChainTypes> ChainCollection<T> {
                 if syncing_id == id {
                     // the finalized chain that was syncing was removed
                     debug_assert!(was_syncing && sync_type == RangeSyncType::Finalized);
-                    let syncing_head_ids: SmallVec<[u64; PARALLEL_HEAD_CHAINS]> = self
+                    let syncing_head_ids: SmallVec<[Id; PARALLEL_HEAD_CHAINS]> = self
                         .head_chains
                         .iter()
                         .filter(|(_id, chain)| chain.is_syncing())
@@ -86,7 +87,7 @@ impl<T: BeaconChainTypes> ChainCollection<T> {
                         RangeSyncState::Head(syncing_head_ids)
                     };
                 } else {
-                    // we removed a head chain, or an stoped finalized chain
+                    // we removed a head chain, or a stopped finalized chain
                     debug_assert!(!was_syncing || sync_type != RangeSyncType::Finalized);
                 }
             }
@@ -355,7 +356,7 @@ impl<T: BeaconChainTypes> ChainCollection<T> {
             .collect::<Vec<_>>();
         preferred_ids.sort_unstable();
 
-        let mut syncing_chains = SmallVec::<[u64; PARALLEL_HEAD_CHAINS]>::new();
+        let mut syncing_chains = SmallVec::<[Id; PARALLEL_HEAD_CHAINS]>::new();
         for (_, _, id) in preferred_ids {
             let chain = self.head_chains.get_mut(&id).expect("known chain");
             if syncing_chains.len() < PARALLEL_HEAD_CHAINS {
@@ -465,15 +466,17 @@ impl<T: BeaconChainTypes> ChainCollection<T> {
         sync_type: RangeSyncType,
         network: &mut SyncNetworkContext<T>,
     ) {
-        let id = SyncingChain::<T>::id(&target_head_root, &target_head_slot);
         let collection = if let RangeSyncType::Finalized = sync_type {
             &mut self.finalized_chains
         } else {
             &mut self.head_chains
         };
-        match collection.entry(id) {
-            Entry::Occupied(mut entry) => {
-                let chain = entry.get_mut();
+
+        match collection
+            .iter_mut()
+            .find(|(_, chain)| chain.has_same_target(target_head_slot, target_head_root))
+        {
+            Some((&id, chain)) => {
                 debug!(self.log, "Adding peer to known chain"; "peer_id" => %peer, "sync_type" => ?sync_type, &chain);
                 debug_assert_eq!(chain.target_head_root, target_head_root);
                 debug_assert_eq!(chain.target_head_slot, target_head_slot);
@@ -483,13 +486,16 @@ impl<T: BeaconChainTypes> ChainCollection<T> {
                     } else {
                         error!(self.log, "Chain removed after adding peer"; "chain" => id, "reason" => ?remove_reason);
                     }
-                    let chain = entry.remove();
-                    self.on_chain_removed(&id, chain.is_syncing(), sync_type);
+                    let is_syncing = chain.is_syncing();
+                    collection.remove(&id);
+                    self.on_chain_removed(&id, is_syncing, sync_type);
                 }
             }
-            Entry::Vacant(entry) => {
+            None => {
                 let peer_rpr = peer.to_string();
+                let id = network.next_id();
                 let new_chain = SyncingChain::new(
+                    id,
                     start_epoch,
                     target_head_slot,
                     target_head_root,
@@ -497,9 +503,8 @@ impl<T: BeaconChainTypes> ChainCollection<T> {
                     sync_type.into(),
                     &self.log,
                 );
-                debug_assert_eq!(new_chain.get_id(), id);
                 debug!(self.log, "New chain added to sync"; "peer_id" => peer_rpr, "sync_type" => ?sync_type, &new_chain);
-                entry.insert(new_chain);
+                collection.insert(id, new_chain);
                 metrics::inc_counter_vec(&metrics::SYNCING_CHAINS_ADDED, &[sync_type.as_str()]);
                 self.update_metrics();
             }
diff --git a/beacon_node/network/src/sync/tests/lookups.rs b/beacon_node/network/src/sync/tests/lookups.rs
index 94aacad3e8..9ab581950c 100644
--- a/beacon_node/network/src/sync/tests/lookups.rs
+++ b/beacon_node/network/src/sync/tests/lookups.rs
@@ -39,11 +39,12 @@ use lighthouse_network::{
 use slog::info;
 use slot_clock::{SlotClock, TestingSlotClock};
 use tokio::sync::mpsc;
+use types::ForkContext;
 use types::{
     data_column_sidecar::ColumnIndex,
     test_utils::{SeedableRng, TestRandom, XorShiftRng},
-    BeaconState, BeaconStateBase, BlobSidecar, DataColumnSidecar, Epoch, EthSpec, ForkName,
-    Hash256, MinimalEthSpec as E, SignedBeaconBlock, Slot,
+    BeaconState, BeaconStateBase, BlobSidecar, DataColumnSidecar, EthSpec, ForkName, Hash256,
+    MinimalEthSpec as E, SignedBeaconBlock, Slot,
 };
 
 const D: Duration = Duration::new(0, 0);
@@ -53,12 +54,8 @@ const SAMPLING_REQUIRED_SUCCESSES: usize = 2;
 type DCByRootIds = Vec<DCByRootId>;
 type DCByRootId = (SyncRequestId, Vec<ColumnIndex>);
 
-struct TestRigConfig {
-    peer_das_enabled: bool,
-}
-
 impl TestRig {
-    fn test_setup_with_config(config: Option<TestRigConfig>) -> Self {
+    pub fn test_setup() -> Self {
         let logger_type = if cfg!(feature = "test_logger") {
             LoggerType::Test
         } else if cfg!(feature = "ci_logger") {
@@ -69,13 +66,7 @@ impl TestRig {
         let log = build_log(slog::Level::Trace, logger_type);
 
         // Use `fork_from_env` logic to set correct fork epochs
-        let mut spec = test_spec::<E>();
-
-        if let Some(config) = config {
-            if config.peer_das_enabled {
-                spec.eip7594_fork_epoch = Some(Epoch::new(0));
-            }
-        }
+        let spec = test_spec::<E>();
 
         // Initialise a new beacon chain
         let harness = BeaconChainHarness::<EphemeralHarnessType<E>>::builder(E)
@@ -92,6 +83,11 @@ impl TestRig {
             .build();
 
         let chain = harness.chain.clone();
+        let fork_context = Arc::new(ForkContext::new::<E>(
+            Slot::new(0),
+            chain.genesis_validators_root,
+            &chain.spec,
+        ));
 
         let (network_tx, network_rx) = mpsc::unbounded_channel();
         let (sync_tx, sync_rx) = mpsc::unbounded_channel::<SyncMessage<E>>();
@@ -119,6 +115,8 @@ impl TestRig {
             .network_globals
             .set_sync_state(SyncState::Synced);
 
+        let spec = chain.spec.clone();
+
         let rng = XorShiftRng::from_seed([42; 16]);
         TestRig {
             beacon_processor_rx,
@@ -137,32 +135,28 @@ impl TestRig {
                 SamplingConfig::Custom {
                     required_successes: vec![SAMPLING_REQUIRED_SUCCESSES],
                 },
+                fork_context,
                 log.clone(),
             ),
             harness,
             fork_name,
             log,
+            spec,
         }
     }
 
-    pub fn test_setup() -> Self {
-        Self::test_setup_with_config(None)
-    }
-
-    fn test_setup_after_deneb() -> Option<Self> {
+    fn test_setup_after_deneb_before_fulu() -> Option<Self> {
         let r = Self::test_setup();
-        if r.after_deneb() {
+        if r.after_deneb() && !r.fork_name.fulu_enabled() {
             Some(r)
         } else {
             None
         }
     }
 
-    fn test_setup_after_peerdas() -> Option<Self> {
-        let r = Self::test_setup_with_config(Some(TestRigConfig {
-            peer_das_enabled: true,
-        }));
-        if r.after_deneb() {
+    fn test_setup_after_fulu() -> Option<Self> {
+        let r = Self::test_setup();
+        if r.fork_name.fulu_enabled() {
             Some(r)
         } else {
             None
@@ -174,7 +168,11 @@ impl TestRig {
     }
 
     pub fn after_deneb(&self) -> bool {
-        matches!(self.fork_name, ForkName::Deneb | ForkName::Electra)
+        self.fork_name.deneb_enabled()
+    }
+
+    pub fn after_fulu(&self) -> bool {
+        self.fork_name.fulu_enabled()
     }
 
     fn trigger_unknown_parent_block(&mut self, peer_id: PeerId, block: Arc<SignedBeaconBlock<E>>) {
@@ -213,7 +211,7 @@ impl TestRig {
     ) -> (SignedBeaconBlock<E>, Vec<BlobSidecar<E>>) {
         let fork_name = self.fork_name;
         let rng = &mut self.rng;
-        generate_rand_block_and_blobs::<E>(fork_name, num_blobs, rng)
+        generate_rand_block_and_blobs::<E>(fork_name, num_blobs, rng, &self.spec)
     }
 
     fn rand_block_and_data_columns(
@@ -377,7 +375,7 @@ impl TestRig {
             .__add_connected_peer_testing_only(false, &self.harness.spec)
     }
 
-    fn new_connected_supernode_peer(&mut self) -> PeerId {
+    pub fn new_connected_supernode_peer(&mut self) -> PeerId {
         self.network_globals
             .peers
             .write()
@@ -1328,8 +1326,10 @@ impl TestRig {
 
 #[test]
 fn stable_rng() {
+    let spec = types::MainnetEthSpec::default_spec();
     let mut rng = XorShiftRng::from_seed([42; 16]);
-    let (block, _) = generate_rand_block_and_blobs::<E>(ForkName::Base, NumBlobs::None, &mut rng);
+    let (block, _) =
+        generate_rand_block_and_blobs::<E>(ForkName::Base, NumBlobs::None, &mut rng, &spec);
     assert_eq!(
         block.canonical_root(),
         Hash256::from_slice(
@@ -1672,7 +1672,7 @@ fn test_parent_lookup_too_many_processing_attempts_must_blacklist() {
         rig.assert_not_failed_chain(block_root);
         // send the right parent but fail processing
         rig.parent_lookup_block_response(id, peer_id, Some(parent.clone().into()));
-        rig.parent_block_processed(block_root, BlockError::InvalidSignature.into());
+        rig.parent_block_processed(block_root, BlockError::BlockSlotLimitReached.into());
         rig.parent_lookup_block_response(id, peer_id, None);
         rig.expect_penalty(peer_id, "lookup_block_processing_failure");
     }
@@ -1933,7 +1933,7 @@ fn test_same_chain_race_condition() {
 
 #[test]
 fn block_in_da_checker_skips_download() {
-    let Some(mut r) = TestRig::test_setup_after_deneb() else {
+    let Some(mut r) = TestRig::test_setup_after_deneb_before_fulu() else {
         return;
     };
     let (block, blobs) = r.rand_block_and_blobs(NumBlobs::Number(1));
@@ -1951,7 +1951,7 @@ fn block_in_da_checker_skips_download() {
 
 #[test]
 fn block_in_processing_cache_becomes_invalid() {
-    let Some(mut r) = TestRig::test_setup_after_deneb() else {
+    let Some(mut r) = TestRig::test_setup_after_deneb_before_fulu() else {
         return;
     };
     let (block, blobs) = r.rand_block_and_blobs(NumBlobs::Number(1));
@@ -1977,7 +1977,7 @@ fn block_in_processing_cache_becomes_invalid() {
 
 #[test]
 fn block_in_processing_cache_becomes_valid_imported() {
-    let Some(mut r) = TestRig::test_setup_after_deneb() else {
+    let Some(mut r) = TestRig::test_setup_after_deneb_before_fulu() else {
         return;
     };
     let (block, blobs) = r.rand_block_and_blobs(NumBlobs::Number(1));
@@ -2002,7 +2002,7 @@ fn block_in_processing_cache_becomes_valid_imported() {
 #[ignore]
 #[test]
 fn blobs_in_da_checker_skip_download() {
-    let Some(mut r) = TestRig::test_setup_after_deneb() else {
+    let Some(mut r) = TestRig::test_setup_after_deneb_before_fulu() else {
         return;
     };
     let (block, blobs) = r.rand_block_and_blobs(NumBlobs::Number(1));
@@ -2021,7 +2021,7 @@ fn blobs_in_da_checker_skip_download() {
 
 #[test]
 fn sampling_happy_path() {
-    let Some(mut r) = TestRig::test_setup_after_peerdas() else {
+    let Some(mut r) = TestRig::test_setup_after_fulu() else {
         return;
     };
     r.new_connected_peers_for_peerdas();
@@ -2038,7 +2038,7 @@ fn sampling_happy_path() {
 
 #[test]
 fn sampling_with_retries() {
-    let Some(mut r) = TestRig::test_setup_after_peerdas() else {
+    let Some(mut r) = TestRig::test_setup_after_fulu() else {
         return;
     };
     r.new_connected_peers_for_peerdas();
@@ -2060,7 +2060,7 @@ fn sampling_with_retries() {
 
 #[test]
 fn sampling_avoid_retrying_same_peer() {
-    let Some(mut r) = TestRig::test_setup_after_peerdas() else {
+    let Some(mut r) = TestRig::test_setup_after_fulu() else {
         return;
     };
     let peer_id_1 = r.new_connected_supernode_peer();
@@ -2081,7 +2081,7 @@ fn sampling_avoid_retrying_same_peer() {
 
 #[test]
 fn sampling_batch_requests() {
-    let Some(mut r) = TestRig::test_setup_after_peerdas() else {
+    let Some(mut r) = TestRig::test_setup_after_fulu() else {
         return;
     };
     let _supernode = r.new_connected_supernode_peer();
@@ -2107,7 +2107,7 @@ fn sampling_batch_requests() {
 
 #[test]
 fn sampling_batch_requests_not_enough_responses_returned() {
-    let Some(mut r) = TestRig::test_setup_after_peerdas() else {
+    let Some(mut r) = TestRig::test_setup_after_fulu() else {
         return;
     };
     let _supernode = r.new_connected_supernode_peer();
@@ -2152,7 +2152,7 @@ fn sampling_batch_requests_not_enough_responses_returned() {
 
 #[test]
 fn custody_lookup_happy_path() {
-    let Some(mut r) = TestRig::test_setup_after_peerdas() else {
+    let Some(mut r) = TestRig::test_setup_after_fulu() else {
         return;
     };
     let spec = E::default_spec();
@@ -2165,7 +2165,7 @@ fn custody_lookup_happy_path() {
     let id = r.expect_block_lookup_request(block.canonical_root());
     r.complete_valid_block_request(id, block.into(), true);
     // for each slot we download `samples_per_slot` columns
-    let sample_column_count = spec.samples_per_slot * spec.data_columns_per_subnet() as u64;
+    let sample_column_count = spec.samples_per_slot * spec.data_columns_per_group();
     let custody_ids =
         r.expect_only_data_columns_by_root_requests(block_root, sample_column_count as usize);
     r.complete_valid_custody_request(custody_ids, data_columns, false);
@@ -2187,8 +2187,8 @@ mod deneb_only {
         block_verification_types::{AsBlock, RpcBlock},
         data_availability_checker::AvailabilityCheckError,
     };
-    use ssz_types::VariableList;
     use std::collections::VecDeque;
+    use types::RuntimeVariableList;
 
     struct DenebTester {
         rig: TestRig,
@@ -2226,7 +2226,7 @@ mod deneb_only {
 
     impl DenebTester {
         fn new(request_trigger: RequestTrigger) -> Option<Self> {
-            let Some(mut rig) = TestRig::test_setup_after_deneb() else {
+            let Some(mut rig) = TestRig::test_setup_after_deneb_before_fulu() else {
                 return None;
             };
             let (block, blobs) = rig.rand_block_and_blobs(NumBlobs::Random);
@@ -2546,12 +2546,15 @@ mod deneb_only {
         fn parent_block_unknown_parent(mut self) -> Self {
             self.rig.log("parent_block_unknown_parent");
             let block = self.unknown_parent_block.take().unwrap();
+            let max_len = self.rig.spec.max_blobs_per_block(block.epoch()) as usize;
             // Now this block is the one we expect requests from
             self.block = block.clone();
             let block = RpcBlock::new(
                 Some(block.canonical_root()),
                 block,
-                self.unknown_parent_blobs.take().map(VariableList::from),
+                self.unknown_parent_blobs
+                    .take()
+                    .map(|vec| RuntimeVariableList::from_vec(vec, max_len)),
             )
             .unwrap();
             self.rig.parent_block_processed(
@@ -2567,7 +2570,7 @@ mod deneb_only {
         fn invalid_parent_processed(mut self) -> Self {
             self.rig.parent_block_processed(
                 self.block_root,
-                BlockProcessingResult::Err(BlockError::ProposalSignatureInvalid),
+                BlockProcessingResult::Err(BlockError::BlockSlotLimitReached),
             );
             assert_eq!(self.rig.active_parent_lookups_count(), 1);
             self
@@ -2576,7 +2579,7 @@ mod deneb_only {
         fn invalid_block_processed(mut self) -> Self {
             self.rig.single_block_component_processed(
                 self.block_req_id.expect("block request id").lookup_id,
-                BlockProcessingResult::Err(BlockError::ProposalSignatureInvalid),
+                BlockProcessingResult::Err(BlockError::BlockSlotLimitReached),
             );
             self.rig.assert_single_lookups_count(1);
             self
@@ -2948,7 +2951,7 @@ mod deneb_only {
     #[ignore]
     #[test]
     fn no_peer_penalty_when_rpc_response_already_known_from_gossip() {
-        let Some(mut r) = TestRig::test_setup_after_deneb() else {
+        let Some(mut r) = TestRig::test_setup_after_deneb_before_fulu() else {
             return;
         };
         let (block, blobs) = r.rand_block_and_blobs(NumBlobs::Number(2));
diff --git a/beacon_node/network/src/sync/tests/mod.rs b/beacon_node/network/src/sync/tests/mod.rs
index 47666b413c..6ed5c7f8fa 100644
--- a/beacon_node/network/src/sync/tests/mod.rs
+++ b/beacon_node/network/src/sync/tests/mod.rs
@@ -12,7 +12,7 @@ use slot_clock::ManualSlotClock;
 use std::sync::Arc;
 use store::MemoryStore;
 use tokio::sync::mpsc;
-use types::{test_utils::XorShiftRng, ForkName, MinimalEthSpec as E};
+use types::{test_utils::XorShiftRng, ChainSpec, ForkName, MinimalEthSpec as E};
 
 mod lookups;
 mod range;
@@ -64,4 +64,5 @@ struct TestRig {
     rng: XorShiftRng,
     fork_name: ForkName,
     log: Logger,
+    spec: Arc<ChainSpec>,
 }
diff --git a/beacon_node/network/src/sync/tests/range.rs b/beacon_node/network/src/sync/tests/range.rs
index 6faa8b7247..cfd89f7b44 100644
--- a/beacon_node/network/src/sync/tests/range.rs
+++ b/beacon_node/network/src/sync/tests/range.rs
@@ -3,16 +3,65 @@ use crate::status::ToStatusMessage;
 use crate::sync::manager::SLOT_IMPORT_TOLERANCE;
 use crate::sync::range_sync::RangeSyncType;
 use crate::sync::SyncMessage;
+use beacon_chain::data_column_verification::CustodyDataColumn;
 use beacon_chain::test_utils::{AttestationStrategy, BlockStrategy};
-use beacon_chain::EngineState;
+use beacon_chain::{block_verification_types::RpcBlock, EngineState, NotifyExecutionLayer};
+use lighthouse_network::rpc::methods::{
+    BlobsByRangeRequest, DataColumnsByRangeRequest, OldBlocksByRangeRequest,
+    OldBlocksByRangeRequestV2,
+};
 use lighthouse_network::rpc::{RequestType, StatusMessage};
 use lighthouse_network::service::api_types::{AppRequestId, Id, SyncRequestId};
 use lighthouse_network::{PeerId, SyncInfo};
 use std::time::Duration;
-use types::{EthSpec, Hash256, MinimalEthSpec as E, SignedBeaconBlock, Slot};
+use types::{
+    BlobSidecarList, BlockImportSource, EthSpec, Hash256, MinimalEthSpec as E, SignedBeaconBlock,
+    SignedBeaconBlockHash, Slot,
+};
 
 const D: Duration = Duration::new(0, 0);
 
+pub(crate) enum DataSidecars<E: EthSpec> {
+    Blobs(BlobSidecarList<E>),
+    DataColumns(Vec<CustodyDataColumn<E>>),
+}
+
+enum ByRangeDataRequestIds {
+    PreDeneb,
+    PrePeerDAS(Id, PeerId),
+    PostPeerDAS(Vec<(Id, PeerId)>),
+}
+
+/// Sync tests are usually written in the form:
+/// - Do some action
+/// - Expect a request to be sent
+/// - Complete the above request
+///
+/// To make writting tests succint, the machinery in this testing rig automatically identifies
+/// _which_ request to complete. Picking the right request is critical for tests to pass, so this
+/// filter allows better expressivity on the criteria to identify the right request.
+#[derive(Default)]
+struct RequestFilter {
+    peer: Option<PeerId>,
+    epoch: Option<u64>,
+}
+
+impl RequestFilter {
+    fn peer(mut self, peer: PeerId) -> Self {
+        self.peer = Some(peer);
+        self
+    }
+
+    fn epoch(mut self, epoch: u64) -> Self {
+        self.epoch = Some(epoch);
+        self
+    }
+}
+
+fn filter() -> RequestFilter {
+    RequestFilter::default()
+}
+
 impl TestRig {
     /// Produce a head peer with an advanced head
     fn add_head_peer(&mut self) -> PeerId {
@@ -64,7 +113,9 @@ impl TestRig {
 
     fn add_peer(&mut self, remote_info: SyncInfo) -> PeerId {
         // Create valid peer known to network globals
-        let peer_id = self.new_connected_peer();
+        // TODO(fulu): Using supernode peers to ensure we have peer across all column
+        // subnets for syncing. Should add tests connecting to full node peers.
+        let peer_id = self.new_connected_supernode_peer();
         // Send peer to sync
         self.send_sync_message(SyncMessage::AddPeer(peer_id, remote_info.clone()));
         peer_id
@@ -83,11 +134,13 @@ impl TestRig {
     }
 
     #[track_caller]
-    fn expect_chain_segment(&mut self) {
-        self.pop_received_processor_event(|ev| {
-            (ev.work_type() == beacon_processor::WorkType::ChainSegment).then_some(())
-        })
-        .unwrap_or_else(|e| panic!("Expect ChainSegment work event: {e:?}"));
+    fn expect_chain_segments(&mut self, count: usize) {
+        for i in 0..count {
+            self.pop_received_processor_event(|ev| {
+                (ev.work_type() == beacon_processor::WorkType::ChainSegment).then_some(())
+            })
+            .unwrap_or_else(|e| panic!("Expect ChainSegment work event count {i}: {e:?}"));
+        }
     }
 
     fn update_execution_engine_state(&mut self, state: EngineState) {
@@ -95,39 +148,80 @@ impl TestRig {
         self.sync_manager.update_execution_engine_state(state);
     }
 
-    fn find_blocks_by_range_request(&mut self, target_peer_id: &PeerId) -> (Id, Option<Id>) {
+    fn find_blocks_by_range_request(
+        &mut self,
+        request_filter: RequestFilter,
+    ) -> ((Id, PeerId), ByRangeDataRequestIds) {
+        let filter_f = |peer: PeerId, start_slot: u64| {
+            if let Some(expected_epoch) = request_filter.epoch {
+                let epoch = Slot::new(start_slot).epoch(E::slots_per_epoch()).as_u64();
+                if epoch != expected_epoch {
+                    return false;
+                }
+            }
+            if let Some(expected_peer) = request_filter.peer {
+                if peer != expected_peer {
+                    return false;
+                }
+            }
+            true
+        };
+
         let block_req_id = self
             .pop_received_network_event(|ev| match ev {
                 NetworkMessage::SendRequest {
                     peer_id,
-                    request: RequestType::BlocksByRange(_),
+                    request:
+                        RequestType::BlocksByRange(OldBlocksByRangeRequest::V2(
+                            OldBlocksByRangeRequestV2 { start_slot, .. },
+                        )),
                     request_id: AppRequestId::Sync(SyncRequestId::RangeBlockAndBlobs { id }),
-                } if peer_id == target_peer_id => Some(*id),
+                } if filter_f(*peer_id, *start_slot) => Some((*id, *peer_id)),
                 _ => None,
             })
             .expect("Should have a blocks by range request");
 
-        let blob_req_id = if self.after_deneb() {
-            Some(
-                self.pop_received_network_event(|ev| match ev {
+        let by_range_data_requests = if self.after_fulu() {
+            let mut data_columns_requests = vec![];
+            while let Ok(data_columns_request) = self.pop_received_network_event(|ev| match ev {
+                NetworkMessage::SendRequest {
+                    peer_id,
+                    request:
+                        RequestType::DataColumnsByRange(DataColumnsByRangeRequest {
+                            start_slot, ..
+                        }),
+                    request_id: AppRequestId::Sync(SyncRequestId::RangeBlockAndBlobs { id }),
+                } if filter_f(*peer_id, *start_slot) => Some((*id, *peer_id)),
+                _ => None,
+            }) {
+                data_columns_requests.push(data_columns_request);
+            }
+            if data_columns_requests.is_empty() {
+                panic!("Found zero DataColumnsByRange requests");
+            }
+            ByRangeDataRequestIds::PostPeerDAS(data_columns_requests)
+        } else if self.after_deneb() {
+            let (id, peer) = self
+                .pop_received_network_event(|ev| match ev {
                     NetworkMessage::SendRequest {
                         peer_id,
-                        request: RequestType::BlobsByRange(_),
+                        request: RequestType::BlobsByRange(BlobsByRangeRequest { start_slot, .. }),
                         request_id: AppRequestId::Sync(SyncRequestId::RangeBlockAndBlobs { id }),
-                    } if peer_id == target_peer_id => Some(*id),
+                    } if filter_f(*peer_id, *start_slot) => Some((*id, *peer_id)),
                     _ => None,
                 })
-                .expect("Should have a blobs by range request"),
-            )
+                .expect("Should have a blobs by range request");
+            ByRangeDataRequestIds::PrePeerDAS(id, peer)
         } else {
-            None
+            ByRangeDataRequestIds::PreDeneb
         };
 
-        (block_req_id, blob_req_id)
+        (block_req_id, by_range_data_requests)
     }
 
-    fn find_and_complete_blocks_by_range_request(&mut self, target_peer_id: PeerId) {
-        let (blocks_req_id, blobs_req_id) = self.find_blocks_by_range_request(&target_peer_id);
+    fn find_and_complete_blocks_by_range_request(&mut self, request_filter: RequestFilter) {
+        let ((blocks_req_id, block_peer), by_range_data_request_ids) =
+            self.find_blocks_by_range_request(request_filter);
 
         // Complete the request with a single stream termination
         self.log(&format!(
@@ -135,26 +229,43 @@ impl TestRig {
         ));
         self.send_sync_message(SyncMessage::RpcBlock {
             request_id: SyncRequestId::RangeBlockAndBlobs { id: blocks_req_id },
-            peer_id: target_peer_id,
+            peer_id: block_peer,
             beacon_block: None,
             seen_timestamp: D,
         });
 
-        if let Some(blobs_req_id) = blobs_req_id {
-            // Complete the request with a single stream termination
-            self.log(&format!(
-                "Completing BlobsByRange request {blobs_req_id} with empty stream"
-            ));
-            self.send_sync_message(SyncMessage::RpcBlob {
-                request_id: SyncRequestId::RangeBlockAndBlobs { id: blobs_req_id },
-                peer_id: target_peer_id,
-                blob_sidecar: None,
-                seen_timestamp: D,
-            });
+        match by_range_data_request_ids {
+            ByRangeDataRequestIds::PreDeneb => {}
+            ByRangeDataRequestIds::PrePeerDAS(id, peer_id) => {
+                // Complete the request with a single stream termination
+                self.log(&format!(
+                    "Completing BlobsByRange request {id} with empty stream"
+                ));
+                self.send_sync_message(SyncMessage::RpcBlob {
+                    request_id: SyncRequestId::RangeBlockAndBlobs { id },
+                    peer_id,
+                    blob_sidecar: None,
+                    seen_timestamp: D,
+                });
+            }
+            ByRangeDataRequestIds::PostPeerDAS(data_column_req_ids) => {
+                // Complete the request with a single stream termination
+                for (id, peer_id) in data_column_req_ids {
+                    self.log(&format!(
+                        "Completing DataColumnsByRange request {id} with empty stream"
+                    ));
+                    self.send_sync_message(SyncMessage::RpcDataColumn {
+                        request_id: SyncRequestId::RangeBlockAndBlobs { id },
+                        peer_id,
+                        data_column: None,
+                        seen_timestamp: D,
+                    });
+                }
+            }
         }
     }
 
-    async fn create_canonical_block(&mut self) -> SignedBeaconBlock<E> {
+    async fn create_canonical_block(&mut self) -> (SignedBeaconBlock<E>, Option<DataSidecars<E>>) {
         self.harness.advance_slot();
 
         let block_root = self
@@ -165,19 +276,73 @@ impl TestRig {
                 AttestationStrategy::AllValidators,
             )
             .await;
-        self.harness
-            .chain
-            .store
-            .get_full_block(&block_root)
-            .unwrap()
-            .unwrap()
+
+        let store = &self.harness.chain.store;
+        let block = store.get_full_block(&block_root).unwrap().unwrap();
+        let fork = block.fork_name_unchecked();
+
+        let data_sidecars = if fork.fulu_enabled() {
+            store
+                .get_data_columns(&block_root)
+                .unwrap()
+                .map(|columns| {
+                    columns
+                        .into_iter()
+                        .map(CustodyDataColumn::from_asserted_custody)
+                        .collect()
+                })
+                .map(DataSidecars::DataColumns)
+        } else if fork.deneb_enabled() {
+            store
+                .get_blobs(&block_root)
+                .unwrap()
+                .blobs()
+                .map(DataSidecars::Blobs)
+        } else {
+            None
+        };
+
+        (block, data_sidecars)
     }
 
-    async fn remember_block(&mut self, block: SignedBeaconBlock<E>) {
-        self.harness
-            .process_block(block.slot(), block.canonical_root(), (block.into(), None))
+    async fn remember_block(
+        &mut self,
+        (block, data_sidecars): (SignedBeaconBlock<E>, Option<DataSidecars<E>>),
+    ) {
+        // This code is kind of duplicated from Harness::process_block, but takes sidecars directly.
+        let block_root = block.canonical_root();
+        self.harness.set_current_slot(block.slot());
+        let _: SignedBeaconBlockHash = self
+            .harness
+            .chain
+            .process_block(
+                block_root,
+                build_rpc_block(block.into(), &data_sidecars, &self.spec),
+                NotifyExecutionLayer::Yes,
+                BlockImportSource::RangeSync,
+                || Ok(()),
+            )
             .await
+            .unwrap()
+            .try_into()
             .unwrap();
+        self.harness.chain.recompute_head_at_current_slot().await;
+    }
+}
+
+fn build_rpc_block(
+    block: Arc<SignedBeaconBlock<E>>,
+    data_sidecars: &Option<DataSidecars<E>>,
+    spec: &ChainSpec,
+) -> RpcBlock<E> {
+    match data_sidecars {
+        Some(DataSidecars::Blobs(blobs)) => {
+            RpcBlock::new(None, block, Some(blobs.clone())).unwrap()
+        }
+        Some(DataSidecars::DataColumns(columns)) => {
+            RpcBlock::new_with_custody_columns(None, block, columns.clone(), spec).unwrap()
+        }
+        None => RpcBlock::new_without_blobs(None, block),
     }
 }
 
@@ -192,14 +357,14 @@ fn head_chain_removed_while_finalized_syncing() {
     rig.assert_state(RangeSyncType::Head);
 
     // Sync should have requested a batch, grab the request.
-    let _ = rig.find_blocks_by_range_request(&head_peer);
+    let _ = rig.find_blocks_by_range_request(filter().peer(head_peer));
 
     // Now get a peer with an advanced finalized epoch.
     let finalized_peer = rig.add_finalized_peer();
     rig.assert_state(RangeSyncType::Finalized);
 
     // Sync should have requested a batch, grab the request
-    let _ = rig.find_blocks_by_range_request(&finalized_peer);
+    let _ = rig.find_blocks_by_range_request(filter().peer(finalized_peer));
 
     // Fail the head chain by disconnecting the peer.
     rig.peer_disconnected(head_peer);
@@ -217,23 +382,23 @@ async fn state_update_while_purging() {
     // Need to create blocks that can be inserted into the fork-choice and fit the "known
     // conditions" below.
     let head_peer_block = rig_2.create_canonical_block().await;
-    let head_peer_root = head_peer_block.canonical_root();
+    let head_peer_root = head_peer_block.0.canonical_root();
     let finalized_peer_block = rig_2.create_canonical_block().await;
-    let finalized_peer_root = finalized_peer_block.canonical_root();
+    let finalized_peer_root = finalized_peer_block.0.canonical_root();
 
     // Get a peer with an advanced head
     let head_peer = rig.add_head_peer_with_root(head_peer_root);
     rig.assert_state(RangeSyncType::Head);
 
     // Sync should have requested a batch, grab the request.
-    let _ = rig.find_blocks_by_range_request(&head_peer);
+    let _ = rig.find_blocks_by_range_request(filter().peer(head_peer));
 
     // Now get a peer with an advanced finalized epoch.
     let finalized_peer = rig.add_finalized_peer_with_root(finalized_peer_root);
     rig.assert_state(RangeSyncType::Finalized);
 
     // Sync should have requested a batch, grab the request
-    let _ = rig.find_blocks_by_range_request(&finalized_peer);
+    let _ = rig.find_blocks_by_range_request(filter().peer(finalized_peer));
 
     // Now the chain knows both chains target roots.
     rig.remember_block(head_peer_block).await;
@@ -252,15 +417,18 @@ fn pause_and_resume_on_ee_offline() {
     // make the ee offline
     rig.update_execution_engine_state(EngineState::Offline);
     // send the response to the request
-    rig.find_and_complete_blocks_by_range_request(peer1);
+    rig.find_and_complete_blocks_by_range_request(filter().peer(peer1).epoch(0));
     // the beacon processor shouldn't have received any work
     rig.expect_empty_processor();
 
     // while the ee is offline, more peers might arrive. Add a new finalized peer.
-    let peer2 = rig.add_finalized_peer();
+    let _peer2 = rig.add_finalized_peer();
 
     // send the response to the request
-    rig.find_and_complete_blocks_by_range_request(peer2);
+    // Don't filter requests and the columns requests may be sent to peer1 or peer2
+    // We need to filter by epoch, because the previous batch eagerly sent requests for the next
+    // epoch for the other batch. So we can either filter by epoch of by sync type.
+    rig.find_and_complete_blocks_by_range_request(filter().epoch(0));
     // the beacon processor shouldn't have received any work
     rig.expect_empty_processor();
     // make the beacon processor available again.
@@ -268,6 +436,6 @@ fn pause_and_resume_on_ee_offline() {
     // now resume range, we should have two processing requests in the beacon processor.
     rig.update_execution_engine_state(EngineState::Online);
 
-    rig.expect_chain_segment();
-    rig.expect_chain_segment();
+    // The head chain and finalized chain (2) should be in the processing queue
+    rig.expect_chain_segments(2);
 }
diff --git a/beacon_node/operation_pool/Cargo.toml b/beacon_node/operation_pool/Cargo.toml
index 5b48e3f0d8..570b74226c 100644
--- a/beacon_node/operation_pool/Cargo.toml
+++ b/beacon_node/operation_pool/Cargo.toml
@@ -5,24 +5,24 @@ authors = ["Michael Sproul <michael@sigmaprime.io>"]
 edition = { workspace = true }
 
 [dependencies]
+bitvec = { workspace = true }
 derivative = { workspace = true }
+ethereum_ssz = { workspace = true }
+ethereum_ssz_derive = { workspace = true }
 itertools = { workspace = true }
 metrics = { workspace = true }
 parking_lot = { workspace = true }
-types = { workspace = true }
-state_processing = { workspace = true }
-ethereum_ssz = { workspace = true }
-ethereum_ssz_derive = { workspace = true }
+rand = { workspace = true }
 rayon = { workspace = true }
 serde = { workspace = true }
+state_processing = { workspace = true }
 store = { workspace = true }
-bitvec = { workspace = true }
-rand = { workspace = true }
+types = { workspace = true }
 
 [dev-dependencies]
 beacon_chain = { workspace = true }
-tokio = { workspace = true }
 maplit = { workspace = true }
+tokio = { workspace = true }
 
 [features]
 portable = ["beacon_chain/portable"]
diff --git a/beacon_node/operation_pool/src/attestation_storage.rs b/beacon_node/operation_pool/src/attestation_storage.rs
index 083c1170f0..49ef5c279c 100644
--- a/beacon_node/operation_pool/src/attestation_storage.rs
+++ b/beacon_node/operation_pool/src/attestation_storage.rs
@@ -214,7 +214,7 @@ impl<E: EthSpec> CompactIndexedAttestationElectra<E> {
                 .is_zero()
     }
 
-    /// Returns `true` if aggregated, otherwise `false`.
+    /// Returns `true` if aggregated, otherwise `false`.
     pub fn aggregate_same_committee(&mut self, other: &Self) -> bool {
         if self.committee_bits != other.committee_bits {
             return false;
diff --git a/beacon_node/operation_pool/src/lib.rs b/beacon_node/operation_pool/src/lib.rs
index d01c73118c..835133a059 100644
--- a/beacon_node/operation_pool/src/lib.rs
+++ b/beacon_node/operation_pool/src/lib.rs
@@ -186,7 +186,7 @@ impl<E: EthSpec> OperationPool<E> {
         self.sync_contributions.write().retain(|_, contributions| {
             // All the contributions in this bucket have the same data, so we only need to
             // check the first one.
-            contributions.first().map_or(false, |contribution| {
+            contributions.first().is_some_and(|contribution| {
                 current_slot <= contribution.slot.saturating_add(Slot::new(1))
             })
         });
@@ -401,7 +401,7 @@ impl<E: EthSpec> OperationPool<E> {
                     && state
                         .validators()
                         .get(slashing.as_inner().signed_header_1.message.proposer_index as usize)
-                        .map_or(false, |validator| !validator.slashed)
+                        .is_some_and(|validator| !validator.slashed)
             },
             |slashing| slashing.as_inner().clone(),
             E::MaxProposerSlashings::to_usize(),
@@ -484,7 +484,7 @@ impl<E: EthSpec> OperationPool<E> {
                     validator.exit_epoch > head_state.finalized_checkpoint().epoch
                 },
             )
-            .map_or(false, |indices| !indices.is_empty());
+            .is_ok_and(|indices| !indices.is_empty());
 
             signature_ok && slashing_ok
         });
@@ -583,9 +583,7 @@ impl<E: EthSpec> OperationPool<E> {
                 address_change.signature_is_still_valid(&state.fork())
                     && state
                         .get_validator(address_change.as_inner().message.validator_index as usize)
-                        .map_or(false, |validator| {
-                            !validator.has_execution_withdrawal_credential(spec)
-                        })
+                        .is_ok_and(|validator| !validator.has_execution_withdrawal_credential(spec))
             },
             |address_change| address_change.as_inner().clone(),
             E::MaxBlsToExecutionChanges::to_usize(),
@@ -609,9 +607,7 @@ impl<E: EthSpec> OperationPool<E> {
                 address_change.signature_is_still_valid(&state.fork())
                     && state
                         .get_validator(address_change.as_inner().message.validator_index as usize)
-                        .map_or(false, |validator| {
-                            !validator.has_eth1_withdrawal_credential(spec)
-                        })
+                        .is_ok_and(|validator| !validator.has_eth1_withdrawal_credential(spec))
             },
             |address_change| address_change.as_inner().clone(),
             usize::MAX,
@@ -1243,14 +1239,11 @@ mod release_tests {
         let stats = op_pool.attestation_stats();
         let fork_name = state.fork_name_unchecked();
 
-        match fork_name {
-            ForkName::Electra => {
-                assert_eq!(stats.num_attestation_data, 1);
-            }
-            _ => {
-                assert_eq!(stats.num_attestation_data, committees.len());
-            }
-        };
+        if fork_name.electra_enabled() {
+            assert_eq!(stats.num_attestation_data, 1);
+        } else {
+            assert_eq!(stats.num_attestation_data, committees.len());
+        }
 
         assert_eq!(
             stats.num_attestations,
@@ -1262,25 +1255,19 @@ mod release_tests {
         let best_attestations = op_pool
             .get_attestations(&state, |_| true, |_| true, spec)
             .expect("should have best attestations");
-        match fork_name {
-            ForkName::Electra => {
-                assert_eq!(best_attestations.len(), 8);
-            }
-            _ => {
-                assert_eq!(best_attestations.len(), max_attestations);
-            }
-        };
+        if fork_name.electra_enabled() {
+            assert_eq!(best_attestations.len(), 8);
+        } else {
+            assert_eq!(best_attestations.len(), max_attestations);
+        }
 
         // All the best attestations should be signed by at least `big_step_size` (4) validators.
         for att in &best_attestations {
-            match fork_name {
-                ForkName::Electra => {
-                    assert!(att.num_set_aggregation_bits() >= small_step_size);
-                }
-                _ => {
-                    assert!(att.num_set_aggregation_bits() >= big_step_size);
-                }
-            };
+            if fork_name.electra_enabled() {
+                assert!(att.num_set_aggregation_bits() >= small_step_size);
+            } else {
+                assert!(att.num_set_aggregation_bits() >= big_step_size);
+            }
         }
     }
 
@@ -1361,17 +1348,14 @@ mod release_tests {
         let num_big = target_committee_size / big_step_size;
         let fork_name = state.fork_name_unchecked();
 
-        match fork_name {
-            ForkName::Electra => {
-                assert_eq!(op_pool.attestation_stats().num_attestation_data, 1);
-            }
-            _ => {
-                assert_eq!(
-                    op_pool.attestation_stats().num_attestation_data,
-                    committees.len()
-                );
-            }
-        };
+        if fork_name.electra_enabled() {
+            assert_eq!(op_pool.attestation_stats().num_attestation_data, 1);
+        } else {
+            assert_eq!(
+                op_pool.attestation_stats().num_attestation_data,
+                committees.len()
+            );
+        }
 
         assert_eq!(
             op_pool.num_attestations(),
@@ -1384,14 +1368,11 @@ mod release_tests {
             .get_attestations(&state, |_| true, |_| true, spec)
             .expect("should have valid best attestations");
 
-        match fork_name {
-            ForkName::Electra => {
-                assert_eq!(best_attestations.len(), 8);
-            }
-            _ => {
-                assert_eq!(best_attestations.len(), max_attestations);
-            }
-        };
+        if fork_name.electra_enabled() {
+            assert_eq!(best_attestations.len(), 8);
+        } else {
+            assert_eq!(best_attestations.len(), max_attestations);
+        }
 
         let total_active_balance = state.get_total_active_balance().unwrap();
 
diff --git a/beacon_node/src/cli.rs b/beacon_node/src/cli.rs
index cecfcee868..1339c15825 100644
--- a/beacon_node/src/cli.rs
+++ b/beacon_node/src/cli.rs
@@ -1591,5 +1591,14 @@ pub fn cli_app() -> Command {
                 .action(ArgAction::Set)
                 .display_order(0)
         )
+        .arg(
+            Arg::new("beacon-node-backend")
+                .long("beacon-node-backend")
+                .value_name("DATABASE")
+                .value_parser(store::config::DatabaseBackend::VARIANTS.to_vec())
+                .help("Set the database backend to be used by the beacon node.")
+                .action(ArgAction::Set)
+                .display_order(0)
+        )
         .group(ArgGroup::new("enable_http").args(["http", "gui", "staking"]).multiple(true))
 }
diff --git a/beacon_node/src/config.rs b/beacon_node/src/config.rs
index 8d8a44a6fd..6d3c18d363 100644
--- a/beacon_node/src/config.rs
+++ b/beacon_node/src/config.rs
@@ -432,6 +432,10 @@ pub fn get_config<E: EthSpec>(
         warn!(log, "The slots-per-restore-point flag is deprecated");
     }
 
+    if let Some(backend) = clap_utils::parse_optional(cli_args, "beacon-node-backend")? {
+        client_config.store.backend = backend;
+    }
+
     if let Some(hierarchy_config) = clap_utils::parse_optional(cli_args, "hierarchy-exponents")? {
         client_config.store.hierarchy_config = hierarchy_config;
     }
diff --git a/beacon_node/src/lib.rs b/beacon_node/src/lib.rs
index cca617d8c6..e3802c837c 100644
--- a/beacon_node/src/lib.rs
+++ b/beacon_node/src/lib.rs
@@ -2,7 +2,6 @@ mod cli;
 mod config;
 
 pub use beacon_chain;
-use beacon_chain::store::LevelDB;
 use beacon_chain::{
     builder::Witness, eth1_chain::CachingEth1Backend, slot_clock::SystemTimeSlotClock,
 };
@@ -16,11 +15,19 @@ use slasher::{DatabaseBackendOverride, Slasher};
 use slog::{info, warn};
 use std::ops::{Deref, DerefMut};
 use std::sync::Arc;
+use store::database::interface::BeaconNodeBackend;
 use types::{ChainSpec, Epoch, EthSpec, ForkName};
 
 /// A type-alias to the tighten the definition of a production-intended `Client`.
-pub type ProductionClient<E> =
-    Client<Witness<SystemTimeSlotClock, CachingEth1Backend<E>, E, LevelDB<E>, LevelDB<E>>>;
+pub type ProductionClient<E> = Client<
+    Witness<
+        SystemTimeSlotClock,
+        CachingEth1Backend<E>,
+        E,
+        BeaconNodeBackend<E>,
+        BeaconNodeBackend<E>,
+    >,
+>;
 
 /// The beacon node `Client` that will be used in production.
 ///
@@ -238,6 +245,7 @@ mod test {
         spec.bellatrix_fork_epoch = Some(Epoch::new(256));
         spec.deneb_fork_epoch = Some(Epoch::new(257));
         spec.electra_fork_epoch = None;
+        spec.fulu_fork_epoch = None;
         let result = validator_fork_epochs(&spec);
         assert_eq!(
             result,
diff --git a/beacon_node/store/Cargo.toml b/beacon_node/store/Cargo.toml
index 21d0cf8dec..d2f3a5c562 100644
--- a/beacon_node/store/Cargo.toml
+++ b/beacon_node/store/Cargo.toml
@@ -4,6 +4,11 @@ version = "0.2.0"
 authors = ["Paul Hauner <paul@paulhauner.com>"]
 edition = { workspace = true }
 
+[features]
+default = ["leveldb"]
+leveldb = ["dep:leveldb"]
+redb = ["dep:redb"]
+
 [dev-dependencies]
 beacon_chain = { workspace = true }
 criterion = { workspace = true }
@@ -17,11 +22,12 @@ directory = { workspace = true }
 ethereum_ssz = { workspace = true }
 ethereum_ssz_derive = { workspace = true }
 itertools = { workspace = true }
-leveldb = { version = "0.8" }
+leveldb = { version = "0.8.6", optional = true }
 logging = { workspace = true }
 lru = { workspace = true }
 metrics = { workspace = true }
 parking_lot = { workspace = true }
+redb = { version = "2.1.3", optional = true }
 safe_arith = { workspace = true }
 serde = { workspace = true }
 slog = { workspace = true }
diff --git a/beacon_node/store/src/blob_sidecar_list_from_root.rs b/beacon_node/store/src/blob_sidecar_list_from_root.rs
new file mode 100644
index 0000000000..de63eaa76c
--- /dev/null
+++ b/beacon_node/store/src/blob_sidecar_list_from_root.rs
@@ -0,0 +1,42 @@
+use std::sync::Arc;
+use types::{BlobSidecar, BlobSidecarList, EthSpec};
+
+#[derive(Debug, Clone)]
+pub enum BlobSidecarListFromRoot<E: EthSpec> {
+    /// Valid root that exists in the DB, but has no blobs associated with it.
+    NoBlobs,
+    /// Contains > 1 blob for the requested root.
+    Blobs(BlobSidecarList<E>),
+    /// No root exists in the db or cache for the requested root.
+    NoRoot,
+}
+
+impl<E: EthSpec> From<BlobSidecarList<E>> for BlobSidecarListFromRoot<E> {
+    fn from(value: BlobSidecarList<E>) -> Self {
+        Self::Blobs(value)
+    }
+}
+
+impl<E: EthSpec> BlobSidecarListFromRoot<E> {
+    pub fn blobs(self) -> Option<BlobSidecarList<E>> {
+        match self {
+            Self::NoBlobs | Self::NoRoot => None,
+            Self::Blobs(blobs) => Some(blobs),
+        }
+    }
+
+    #[allow(clippy::len_without_is_empty)]
+    pub fn len(&self) -> usize {
+        match self {
+            Self::NoBlobs | Self::NoRoot => 0,
+            Self::Blobs(blobs) => blobs.len(),
+        }
+    }
+
+    pub fn iter(&self) -> impl Iterator<Item = &Arc<BlobSidecar<E>>> {
+        match self {
+            Self::NoBlobs | Self::NoRoot => [].iter(),
+            Self::Blobs(list) => list.iter(),
+        }
+    }
+}
diff --git a/beacon_node/store/src/chunked_vector.rs b/beacon_node/store/src/chunked_vector.rs
index 83b8da2a18..90e8c17310 100644
--- a/beacon_node/store/src/chunked_vector.rs
+++ b/beacon_node/store/src/chunked_vector.rs
@@ -680,7 +680,7 @@ where
         key: &[u8],
     ) -> Result<Option<Self>, Error> {
         store
-            .get_bytes(column.into(), key)?
+            .get_bytes(column, key)?
             .map(|bytes| Self::decode(&bytes))
             .transpose()
     }
@@ -691,8 +691,11 @@ where
         key: &[u8],
         ops: &mut Vec<KeyValueStoreOp>,
     ) -> Result<(), Error> {
-        let db_key = get_key_for_col(column.into(), key);
-        ops.push(KeyValueStoreOp::PutKeyValue(db_key, self.encode()?));
+        ops.push(KeyValueStoreOp::PutKeyValue(
+            column,
+            key.to_vec(),
+            self.encode()?,
+        ));
         Ok(())
     }
 
diff --git a/beacon_node/store/src/config.rs b/beacon_node/store/src/config.rs
index 4f67530570..64765fd66a 100644
--- a/beacon_node/store/src/config.rs
+++ b/beacon_node/store/src/config.rs
@@ -1,16 +1,23 @@
 use crate::hdiff::HierarchyConfig;
+use crate::superstruct;
 use crate::{AnchorInfo, DBColumn, Error, Split, StoreItem};
 use serde::{Deserialize, Serialize};
 use ssz::{Decode, Encode};
 use ssz_derive::{Decode, Encode};
 use std::io::Write;
 use std::num::NonZeroUsize;
-use superstruct::superstruct;
+use strum::{Display, EnumString, EnumVariantNames};
 use types::non_zero_usize::new_non_zero_usize;
 use types::EthSpec;
 use zstd::Encoder;
 
-// Only used in tests. Mainnet sets a higher default on the CLI.
+#[cfg(all(feature = "redb", not(feature = "leveldb")))]
+pub const DEFAULT_BACKEND: DatabaseBackend = DatabaseBackend::Redb;
+#[cfg(feature = "leveldb")]
+pub const DEFAULT_BACKEND: DatabaseBackend = DatabaseBackend::LevelDb;
+
+pub const PREV_DEFAULT_SLOTS_PER_RESTORE_POINT: u64 = 2048;
+pub const DEFAULT_SLOTS_PER_RESTORE_POINT: u64 = 8192;
 pub const DEFAULT_EPOCHS_PER_STATE_DIFF: u64 = 8;
 pub const DEFAULT_BLOCK_CACHE_SIZE: NonZeroUsize = new_non_zero_usize(64);
 pub const DEFAULT_STATE_CACHE_SIZE: NonZeroUsize = new_non_zero_usize(128);
@@ -40,6 +47,8 @@ pub struct StoreConfig {
     pub compact_on_prune: bool,
     /// Whether to prune payloads on initialization and finalization.
     pub prune_payloads: bool,
+    /// Database backend to use.
+    pub backend: DatabaseBackend,
     /// State diff hierarchy.
     pub hierarchy_config: HierarchyConfig,
     /// Whether to prune blobs older than the blob data availability boundary.
@@ -104,6 +113,7 @@ impl Default for StoreConfig {
             compact_on_init: false,
             compact_on_prune: true,
             prune_payloads: true,
+            backend: DEFAULT_BACKEND,
             hierarchy_config: HierarchyConfig::default(),
             prune_blobs: true,
             epochs_per_blob_prune: DEFAULT_EPOCHS_PER_BLOB_PRUNE,
@@ -340,3 +350,14 @@ mod test {
         assert_eq!(config_out, config);
     }
 }
+
+#[derive(
+    Debug, Clone, Copy, Eq, PartialEq, Serialize, Deserialize, Display, EnumString, EnumVariantNames,
+)]
+#[strum(serialize_all = "lowercase")]
+pub enum DatabaseBackend {
+    #[cfg(feature = "leveldb")]
+    LevelDb,
+    #[cfg(feature = "redb")]
+    Redb,
+}
diff --git a/beacon_node/store/src/database.rs b/beacon_node/store/src/database.rs
new file mode 100644
index 0000000000..2232f73c5c
--- /dev/null
+++ b/beacon_node/store/src/database.rs
@@ -0,0 +1,5 @@
+pub mod interface;
+#[cfg(feature = "leveldb")]
+pub mod leveldb_impl;
+#[cfg(feature = "redb")]
+pub mod redb_impl;
diff --git a/beacon_node/store/src/database/interface.rs b/beacon_node/store/src/database/interface.rs
new file mode 100644
index 0000000000..b213433241
--- /dev/null
+++ b/beacon_node/store/src/database/interface.rs
@@ -0,0 +1,220 @@
+#[cfg(feature = "leveldb")]
+use crate::database::leveldb_impl;
+#[cfg(feature = "redb")]
+use crate::database::redb_impl;
+use crate::{config::DatabaseBackend, KeyValueStoreOp, StoreConfig};
+use crate::{metrics, ColumnIter, ColumnKeyIter, DBColumn, Error, ItemStore, Key, KeyValueStore};
+use std::collections::HashSet;
+use std::path::Path;
+use types::EthSpec;
+
+pub enum BeaconNodeBackend<E: EthSpec> {
+    #[cfg(feature = "leveldb")]
+    LevelDb(leveldb_impl::LevelDB<E>),
+    #[cfg(feature = "redb")]
+    Redb(redb_impl::Redb<E>),
+}
+
+impl<E: EthSpec> ItemStore<E> for BeaconNodeBackend<E> {}
+
+impl<E: EthSpec> KeyValueStore<E> for BeaconNodeBackend<E> {
+    fn get_bytes(&self, column: DBColumn, key: &[u8]) -> Result<Option<Vec<u8>>, Error> {
+        match self {
+            #[cfg(feature = "leveldb")]
+            BeaconNodeBackend::LevelDb(txn) => leveldb_impl::LevelDB::get_bytes(txn, column, key),
+            #[cfg(feature = "redb")]
+            BeaconNodeBackend::Redb(txn) => redb_impl::Redb::get_bytes(txn, column, key),
+        }
+    }
+
+    fn put_bytes(&self, column: DBColumn, key: &[u8], value: &[u8]) -> Result<(), Error> {
+        match self {
+            #[cfg(feature = "leveldb")]
+            BeaconNodeBackend::LevelDb(txn) => leveldb_impl::LevelDB::put_bytes_with_options(
+                txn,
+                column,
+                key,
+                value,
+                txn.write_options(),
+            ),
+            #[cfg(feature = "redb")]
+            BeaconNodeBackend::Redb(txn) => redb_impl::Redb::put_bytes_with_options(
+                txn,
+                column,
+                key,
+                value,
+                txn.write_options(),
+            ),
+        }
+    }
+
+    fn put_bytes_sync(&self, column: DBColumn, key: &[u8], value: &[u8]) -> Result<(), Error> {
+        match self {
+            #[cfg(feature = "leveldb")]
+            BeaconNodeBackend::LevelDb(txn) => leveldb_impl::LevelDB::put_bytes_with_options(
+                txn,
+                column,
+                key,
+                value,
+                txn.write_options_sync(),
+            ),
+            #[cfg(feature = "redb")]
+            BeaconNodeBackend::Redb(txn) => redb_impl::Redb::put_bytes_with_options(
+                txn,
+                column,
+                key,
+                value,
+                txn.write_options_sync(),
+            ),
+        }
+    }
+
+    fn sync(&self) -> Result<(), Error> {
+        match self {
+            #[cfg(feature = "leveldb")]
+            BeaconNodeBackend::LevelDb(txn) => leveldb_impl::LevelDB::sync(txn),
+            #[cfg(feature = "redb")]
+            BeaconNodeBackend::Redb(txn) => redb_impl::Redb::sync(txn),
+        }
+    }
+
+    fn key_exists(&self, column: DBColumn, key: &[u8]) -> Result<bool, Error> {
+        match self {
+            #[cfg(feature = "leveldb")]
+            BeaconNodeBackend::LevelDb(txn) => leveldb_impl::LevelDB::key_exists(txn, column, key),
+            #[cfg(feature = "redb")]
+            BeaconNodeBackend::Redb(txn) => redb_impl::Redb::key_exists(txn, column, key),
+        }
+    }
+
+    fn key_delete(&self, column: DBColumn, key: &[u8]) -> Result<(), Error> {
+        match self {
+            #[cfg(feature = "leveldb")]
+            BeaconNodeBackend::LevelDb(txn) => leveldb_impl::LevelDB::key_delete(txn, column, key),
+            #[cfg(feature = "redb")]
+            BeaconNodeBackend::Redb(txn) => redb_impl::Redb::key_delete(txn, column, key),
+        }
+    }
+
+    fn do_atomically(&self, batch: Vec<KeyValueStoreOp>) -> Result<(), Error> {
+        match self {
+            #[cfg(feature = "leveldb")]
+            BeaconNodeBackend::LevelDb(txn) => leveldb_impl::LevelDB::do_atomically(txn, batch),
+            #[cfg(feature = "redb")]
+            BeaconNodeBackend::Redb(txn) => redb_impl::Redb::do_atomically(txn, batch),
+        }
+    }
+
+    fn begin_rw_transaction(&self) -> parking_lot::MutexGuard<()> {
+        match self {
+            #[cfg(feature = "leveldb")]
+            BeaconNodeBackend::LevelDb(txn) => leveldb_impl::LevelDB::begin_rw_transaction(txn),
+            #[cfg(feature = "redb")]
+            BeaconNodeBackend::Redb(txn) => redb_impl::Redb::begin_rw_transaction(txn),
+        }
+    }
+
+    fn compact(&self) -> Result<(), Error> {
+        match self {
+            #[cfg(feature = "leveldb")]
+            BeaconNodeBackend::LevelDb(txn) => leveldb_impl::LevelDB::compact(txn),
+            #[cfg(feature = "redb")]
+            BeaconNodeBackend::Redb(txn) => redb_impl::Redb::compact(txn),
+        }
+    }
+
+    fn iter_column_keys_from<K: Key>(&self, _column: DBColumn, from: &[u8]) -> ColumnKeyIter<K> {
+        match self {
+            #[cfg(feature = "leveldb")]
+            BeaconNodeBackend::LevelDb(txn) => {
+                leveldb_impl::LevelDB::iter_column_keys_from(txn, _column, from)
+            }
+            #[cfg(feature = "redb")]
+            BeaconNodeBackend::Redb(txn) => {
+                redb_impl::Redb::iter_column_keys_from(txn, _column, from)
+            }
+        }
+    }
+
+    fn iter_column_keys<K: Key>(&self, column: DBColumn) -> ColumnKeyIter<K> {
+        match self {
+            #[cfg(feature = "leveldb")]
+            BeaconNodeBackend::LevelDb(txn) => leveldb_impl::LevelDB::iter_column_keys(txn, column),
+            #[cfg(feature = "redb")]
+            BeaconNodeBackend::Redb(txn) => redb_impl::Redb::iter_column_keys(txn, column),
+        }
+    }
+
+    fn iter_column_from<K: Key>(&self, column: DBColumn, from: &[u8]) -> ColumnIter<K> {
+        match self {
+            #[cfg(feature = "leveldb")]
+            BeaconNodeBackend::LevelDb(txn) => {
+                leveldb_impl::LevelDB::iter_column_from(txn, column, from)
+            }
+            #[cfg(feature = "redb")]
+            BeaconNodeBackend::Redb(txn) => redb_impl::Redb::iter_column_from(txn, column, from),
+        }
+    }
+
+    fn compact_column(&self, _column: DBColumn) -> Result<(), Error> {
+        match self {
+            #[cfg(feature = "leveldb")]
+            BeaconNodeBackend::LevelDb(txn) => leveldb_impl::LevelDB::compact_column(txn, _column),
+            #[cfg(feature = "redb")]
+            BeaconNodeBackend::Redb(txn) => redb_impl::Redb::compact(txn),
+        }
+    }
+
+    fn delete_batch(&self, col: DBColumn, ops: HashSet<&[u8]>) -> Result<(), Error> {
+        match self {
+            #[cfg(feature = "leveldb")]
+            BeaconNodeBackend::LevelDb(txn) => leveldb_impl::LevelDB::delete_batch(txn, col, ops),
+            #[cfg(feature = "redb")]
+            BeaconNodeBackend::Redb(txn) => redb_impl::Redb::delete_batch(txn, col, ops),
+        }
+    }
+
+    fn delete_if(
+        &self,
+        column: DBColumn,
+        f: impl FnMut(&[u8]) -> Result<bool, Error>,
+    ) -> Result<(), Error> {
+        match self {
+            #[cfg(feature = "leveldb")]
+            BeaconNodeBackend::LevelDb(txn) => leveldb_impl::LevelDB::delete_if(txn, column, f),
+            #[cfg(feature = "redb")]
+            BeaconNodeBackend::Redb(txn) => redb_impl::Redb::delete_if(txn, column, f),
+        }
+    }
+}
+
+impl<E: EthSpec> BeaconNodeBackend<E> {
+    pub fn open(config: &StoreConfig, path: &Path) -> Result<Self, Error> {
+        metrics::inc_counter_vec(&metrics::DISK_DB_TYPE, &[&config.backend.to_string()]);
+        match config.backend {
+            #[cfg(feature = "leveldb")]
+            DatabaseBackend::LevelDb => {
+                leveldb_impl::LevelDB::open(path).map(BeaconNodeBackend::LevelDb)
+            }
+            #[cfg(feature = "redb")]
+            DatabaseBackend::Redb => redb_impl::Redb::open(path).map(BeaconNodeBackend::Redb),
+        }
+    }
+}
+
+pub struct WriteOptions {
+    /// fsync before acknowledging a write operation.
+    pub sync: bool,
+}
+
+impl WriteOptions {
+    pub fn new() -> Self {
+        WriteOptions { sync: false }
+    }
+}
+
+impl Default for WriteOptions {
+    fn default() -> Self {
+        Self::new()
+    }
+}
diff --git a/beacon_node/store/src/database/leveldb_impl.rs b/beacon_node/store/src/database/leveldb_impl.rs
new file mode 100644
index 0000000000..3d8bbe1473
--- /dev/null
+++ b/beacon_node/store/src/database/leveldb_impl.rs
@@ -0,0 +1,304 @@
+use crate::hot_cold_store::{BytesKey, HotColdDBError};
+use crate::Key;
+use crate::{
+    get_key_for_col, metrics, ColumnIter, ColumnKeyIter, DBColumn, Error, KeyValueStoreOp,
+};
+use leveldb::{
+    compaction::Compaction,
+    database::{
+        batch::{Batch, Writebatch},
+        kv::KV,
+        Database,
+    },
+    iterator::{Iterable, LevelDBIterator},
+    options::{Options, ReadOptions},
+};
+use parking_lot::{Mutex, MutexGuard};
+use std::collections::HashSet;
+use std::marker::PhantomData;
+use std::path::Path;
+use types::{EthSpec, FixedBytesExtended, Hash256};
+
+use super::interface::WriteOptions;
+
+pub struct LevelDB<E: EthSpec> {
+    db: Database<BytesKey>,
+    /// A mutex to synchronise sensitive read-write transactions.
+    transaction_mutex: Mutex<()>,
+    _phantom: PhantomData<E>,
+}
+
+impl From<WriteOptions> for leveldb::options::WriteOptions {
+    fn from(options: WriteOptions) -> Self {
+        let mut opts = leveldb::options::WriteOptions::new();
+        opts.sync = options.sync;
+        opts
+    }
+}
+
+impl<E: EthSpec> LevelDB<E> {
+    pub fn open(path: &Path) -> Result<Self, Error> {
+        let mut options = Options::new();
+
+        options.create_if_missing = true;
+
+        let db = Database::open(path, options)?;
+        let transaction_mutex = Mutex::new(());
+
+        Ok(Self {
+            db,
+            transaction_mutex,
+            _phantom: PhantomData,
+        })
+    }
+
+    pub fn read_options(&self) -> ReadOptions<BytesKey> {
+        ReadOptions::new()
+    }
+
+    pub fn write_options(&self) -> WriteOptions {
+        WriteOptions::new()
+    }
+
+    pub fn write_options_sync(&self) -> WriteOptions {
+        let mut opts = WriteOptions::new();
+        opts.sync = true;
+        opts
+    }
+
+    pub fn put_bytes_with_options(
+        &self,
+        col: DBColumn,
+        key: &[u8],
+        val: &[u8],
+        opts: WriteOptions,
+    ) -> Result<(), Error> {
+        let column_key = get_key_for_col(col, key);
+
+        metrics::inc_counter_vec(&metrics::DISK_DB_WRITE_COUNT, &[col.into()]);
+        metrics::inc_counter_vec_by(
+            &metrics::DISK_DB_WRITE_BYTES,
+            &[col.into()],
+            val.len() as u64,
+        );
+        let timer = metrics::start_timer(&metrics::DISK_DB_WRITE_TIMES);
+
+        self.db
+            .put(opts.into(), BytesKey::from_vec(column_key), val)
+            .map_err(Into::into)
+            .map(|()| {
+                metrics::stop_timer(timer);
+            })
+    }
+
+    /// Store some `value` in `column`, indexed with `key`.
+    pub fn put_bytes(&self, col: DBColumn, key: &[u8], val: &[u8]) -> Result<(), Error> {
+        self.put_bytes_with_options(col, key, val, self.write_options())
+    }
+
+    pub fn put_bytes_sync(&self, col: DBColumn, key: &[u8], val: &[u8]) -> Result<(), Error> {
+        self.put_bytes_with_options(col, key, val, self.write_options_sync())
+    }
+
+    pub fn sync(&self) -> Result<(), Error> {
+        self.put_bytes_sync(DBColumn::Dummy, b"sync", b"sync")
+    }
+
+    // Retrieve some bytes in `column` with `key`.
+    pub fn get_bytes(&self, col: DBColumn, key: &[u8]) -> Result<Option<Vec<u8>>, Error> {
+        let column_key = get_key_for_col(col, key);
+
+        metrics::inc_counter_vec(&metrics::DISK_DB_READ_COUNT, &[col.into()]);
+        let timer = metrics::start_timer(&metrics::DISK_DB_READ_TIMES);
+
+        self.db
+            .get(self.read_options(), BytesKey::from_vec(column_key))
+            .map_err(Into::into)
+            .map(|opt| {
+                opt.inspect(|bytes| {
+                    metrics::inc_counter_vec_by(
+                        &metrics::DISK_DB_READ_BYTES,
+                        &[col.into()],
+                        bytes.len() as u64,
+                    );
+                    metrics::stop_timer(timer);
+                })
+            })
+    }
+
+    /// Return `true` if `key` exists in `column`.
+    pub fn key_exists(&self, col: DBColumn, key: &[u8]) -> Result<bool, Error> {
+        let column_key = get_key_for_col(col, key);
+
+        metrics::inc_counter_vec(&metrics::DISK_DB_EXISTS_COUNT, &[col.into()]);
+
+        self.db
+            .get(self.read_options(), BytesKey::from_vec(column_key))
+            .map_err(Into::into)
+            .map(|val| val.is_some())
+    }
+
+    /// Removes `key` from `column`.
+    pub fn key_delete(&self, col: DBColumn, key: &[u8]) -> Result<(), Error> {
+        let column_key = get_key_for_col(col, key);
+
+        metrics::inc_counter_vec(&metrics::DISK_DB_DELETE_COUNT, &[col.into()]);
+
+        self.db
+            .delete(self.write_options().into(), BytesKey::from_vec(column_key))
+            .map_err(Into::into)
+    }
+
+    pub fn do_atomically(&self, ops_batch: Vec<KeyValueStoreOp>) -> Result<(), Error> {
+        let mut leveldb_batch = Writebatch::new();
+        for op in ops_batch {
+            match op {
+                KeyValueStoreOp::PutKeyValue(col, key, value) => {
+                    let _timer = metrics::start_timer(&metrics::DISK_DB_WRITE_TIMES);
+                    metrics::inc_counter_vec_by(
+                        &metrics::DISK_DB_WRITE_BYTES,
+                        &[col.into()],
+                        value.len() as u64,
+                    );
+                    metrics::inc_counter_vec(&metrics::DISK_DB_WRITE_COUNT, &[col.into()]);
+                    let column_key = get_key_for_col(col, &key);
+                    leveldb_batch.put(BytesKey::from_vec(column_key), &value);
+                }
+
+                KeyValueStoreOp::DeleteKey(col, key) => {
+                    let _timer = metrics::start_timer(&metrics::DISK_DB_DELETE_TIMES);
+                    metrics::inc_counter_vec(&metrics::DISK_DB_DELETE_COUNT, &[col.into()]);
+                    let column_key = get_key_for_col(col, &key);
+                    leveldb_batch.delete(BytesKey::from_vec(column_key));
+                }
+            }
+        }
+        self.db.write(self.write_options().into(), &leveldb_batch)?;
+        Ok(())
+    }
+
+    pub fn begin_rw_transaction(&self) -> MutexGuard<()> {
+        self.transaction_mutex.lock()
+    }
+
+    /// Compact all values in the states and states flag columns.
+    pub fn compact(&self) -> Result<(), Error> {
+        let _timer = metrics::start_timer(&metrics::DISK_DB_COMPACT_TIMES);
+        let endpoints = |column: DBColumn| {
+            (
+                BytesKey::from_vec(get_key_for_col(column, Hash256::zero().as_slice())),
+                BytesKey::from_vec(get_key_for_col(
+                    column,
+                    Hash256::repeat_byte(0xff).as_slice(),
+                )),
+            )
+        };
+
+        for (start_key, end_key) in [
+            endpoints(DBColumn::BeaconStateTemporary),
+            endpoints(DBColumn::BeaconState),
+            endpoints(DBColumn::BeaconStateSummary),
+        ] {
+            self.db.compact(&start_key, &end_key);
+        }
+
+        Ok(())
+    }
+
+    pub fn compact_column(&self, column: DBColumn) -> Result<(), Error> {
+        // Use key-size-agnostic keys [] and 0xff..ff with a minimum of 32 bytes to account for
+        // columns that may change size between sub-databases or schema versions.
+        let start_key = BytesKey::from_vec(get_key_for_col(column, &[]));
+        let end_key = BytesKey::from_vec(get_key_for_col(
+            column,
+            &vec![0xff; std::cmp::max(column.key_size(), 32)],
+        ));
+        self.db.compact(&start_key, &end_key);
+        Ok(())
+    }
+
+    pub fn iter_column_from<K: Key>(&self, column: DBColumn, from: &[u8]) -> ColumnIter<K> {
+        let start_key = BytesKey::from_vec(get_key_for_col(column, from));
+        let iter = self.db.iter(self.read_options());
+        iter.seek(&start_key);
+
+        Box::new(
+            iter.take_while(move |(key, _)| key.matches_column(column))
+                .map(move |(bytes_key, value)| {
+                    metrics::inc_counter_vec(&metrics::DISK_DB_READ_COUNT, &[column.into()]);
+                    metrics::inc_counter_vec_by(
+                        &metrics::DISK_DB_READ_BYTES,
+                        &[column.into()],
+                        value.len() as u64,
+                    );
+                    let key = bytes_key.remove_column_variable(column).ok_or_else(|| {
+                        HotColdDBError::IterationError {
+                            unexpected_key: bytes_key.clone(),
+                        }
+                    })?;
+                    Ok((K::from_bytes(key)?, value))
+                }),
+        )
+    }
+
+    pub fn iter_column_keys_from<K: Key>(&self, column: DBColumn, from: &[u8]) -> ColumnKeyIter<K> {
+        let start_key = BytesKey::from_vec(get_key_for_col(column, from));
+
+        let iter = self.db.keys_iter(self.read_options());
+        iter.seek(&start_key);
+
+        Box::new(
+            iter.take_while(move |key| key.matches_column(column))
+                .map(move |bytes_key| {
+                    metrics::inc_counter_vec(&metrics::DISK_DB_KEY_READ_COUNT, &[column.into()]);
+                    metrics::inc_counter_vec_by(
+                        &metrics::DISK_DB_KEY_READ_BYTES,
+                        &[column.into()],
+                        bytes_key.key.len() as u64,
+                    );
+                    let key = &bytes_key.key[column.as_bytes().len()..];
+                    K::from_bytes(key)
+                }),
+        )
+    }
+
+    /// Iterate through all keys and values in a particular column.
+    pub fn iter_column_keys<K: Key>(&self, column: DBColumn) -> ColumnKeyIter<K> {
+        self.iter_column_keys_from(column, &vec![0; column.key_size()])
+    }
+
+    pub fn iter_column<K: Key>(&self, column: DBColumn) -> ColumnIter<K> {
+        self.iter_column_from(column, &vec![0; column.key_size()])
+    }
+
+    pub fn delete_batch(&self, col: DBColumn, ops: HashSet<&[u8]>) -> Result<(), Error> {
+        let mut leveldb_batch = Writebatch::new();
+        for op in ops {
+            let column_key = get_key_for_col(col, op);
+            leveldb_batch.delete(BytesKey::from_vec(column_key));
+        }
+        self.db.write(self.write_options().into(), &leveldb_batch)?;
+        Ok(())
+    }
+
+    pub fn delete_if(
+        &self,
+        column: DBColumn,
+        mut f: impl FnMut(&[u8]) -> Result<bool, Error>,
+    ) -> Result<(), Error> {
+        let mut leveldb_batch = Writebatch::new();
+        let iter = self.db.iter(self.read_options());
+
+        iter.take_while(move |(key, _)| key.matches_column(column))
+            .for_each(|(key, value)| {
+                if f(&value).unwrap_or(false) {
+                    let _timer = metrics::start_timer(&metrics::DISK_DB_DELETE_TIMES);
+                    metrics::inc_counter_vec(&metrics::DISK_DB_DELETE_COUNT, &[column.into()]);
+                    leveldb_batch.delete(key);
+                }
+            });
+
+        self.db.write(self.write_options().into(), &leveldb_batch)?;
+        Ok(())
+    }
+}
diff --git a/beacon_node/store/src/database/redb_impl.rs b/beacon_node/store/src/database/redb_impl.rs
new file mode 100644
index 0000000000..cbe575d184
--- /dev/null
+++ b/beacon_node/store/src/database/redb_impl.rs
@@ -0,0 +1,319 @@
+use crate::{metrics, ColumnIter, ColumnKeyIter, Key};
+use crate::{DBColumn, Error, KeyValueStoreOp};
+use parking_lot::{Mutex, MutexGuard, RwLock};
+use redb::TableDefinition;
+use std::collections::HashSet;
+use std::{borrow::BorrowMut, marker::PhantomData, path::Path};
+use strum::IntoEnumIterator;
+use types::EthSpec;
+
+use super::interface::WriteOptions;
+
+pub const DB_FILE_NAME: &str = "database.redb";
+
+pub struct Redb<E: EthSpec> {
+    db: RwLock<redb::Database>,
+    transaction_mutex: Mutex<()>,
+    _phantom: PhantomData<E>,
+}
+
+impl From<WriteOptions> for redb::Durability {
+    fn from(options: WriteOptions) -> Self {
+        if options.sync {
+            redb::Durability::Immediate
+        } else {
+            redb::Durability::Eventual
+        }
+    }
+}
+
+impl<E: EthSpec> Redb<E> {
+    pub fn open(path: &Path) -> Result<Self, Error> {
+        let db_file = path.join(DB_FILE_NAME);
+        let db = redb::Database::create(db_file)?;
+        let transaction_mutex = Mutex::new(());
+
+        for column in DBColumn::iter() {
+            Redb::<E>::create_table(&db, column.into())?;
+        }
+
+        Ok(Self {
+            db: db.into(),
+            transaction_mutex,
+            _phantom: PhantomData,
+        })
+    }
+
+    fn create_table(db: &redb::Database, table_name: &str) -> Result<(), Error> {
+        let table_definition: TableDefinition<'_, &[u8], &[u8]> = TableDefinition::new(table_name);
+        let tx = db.begin_write()?;
+        tx.open_table(table_definition)?;
+        tx.commit().map_err(Into::into)
+    }
+
+    pub fn write_options(&self) -> WriteOptions {
+        WriteOptions::new()
+    }
+
+    pub fn write_options_sync(&self) -> WriteOptions {
+        let mut opts = WriteOptions::new();
+        opts.sync = true;
+        opts
+    }
+
+    pub fn begin_rw_transaction(&self) -> MutexGuard<()> {
+        self.transaction_mutex.lock()
+    }
+
+    pub fn put_bytes_with_options(
+        &self,
+        col: DBColumn,
+        key: &[u8],
+        val: &[u8],
+        opts: WriteOptions,
+    ) -> Result<(), Error> {
+        metrics::inc_counter_vec(&metrics::DISK_DB_WRITE_COUNT, &[col.into()]);
+        metrics::inc_counter_vec_by(
+            &metrics::DISK_DB_WRITE_BYTES,
+            &[col.into()],
+            val.len() as u64,
+        );
+        let timer = metrics::start_timer(&metrics::DISK_DB_WRITE_TIMES);
+
+        let table_definition: TableDefinition<'_, &[u8], &[u8]> = TableDefinition::new(col.into());
+        let open_db = self.db.read();
+        let mut tx = open_db.begin_write()?;
+        tx.set_durability(opts.into());
+        let mut table = tx.open_table(table_definition)?;
+
+        table.insert(key, val).map(|_| {
+            metrics::stop_timer(timer);
+        })?;
+        drop(table);
+        tx.commit().map_err(Into::into)
+    }
+
+    /// Store some `value` in `column`, indexed with `key`.
+    pub fn put_bytes(&self, col: DBColumn, key: &[u8], val: &[u8]) -> Result<(), Error> {
+        self.put_bytes_with_options(col, key, val, self.write_options())
+    }
+
+    pub fn put_bytes_sync(&self, col: DBColumn, key: &[u8], val: &[u8]) -> Result<(), Error> {
+        self.put_bytes_with_options(col, key, val, self.write_options_sync())
+    }
+
+    pub fn sync(&self) -> Result<(), Error> {
+        self.put_bytes_sync(DBColumn::Dummy, b"sync", b"sync")
+    }
+
+    // Retrieve some bytes in `column` with `key`.
+    pub fn get_bytes(&self, col: DBColumn, key: &[u8]) -> Result<Option<Vec<u8>>, Error> {
+        metrics::inc_counter_vec(&metrics::DISK_DB_READ_COUNT, &[col.into()]);
+        let timer = metrics::start_timer(&metrics::DISK_DB_READ_TIMES);
+
+        let table_definition: TableDefinition<'_, &[u8], &[u8]> = TableDefinition::new(col.into());
+        let open_db = self.db.read();
+        let tx = open_db.begin_read()?;
+        let table = tx.open_table(table_definition)?;
+
+        let result = table.get(key)?;
+
+        match result {
+            Some(access_guard) => {
+                let value = access_guard.value().to_vec();
+                metrics::inc_counter_vec_by(
+                    &metrics::DISK_DB_READ_BYTES,
+                    &[col.into()],
+                    value.len() as u64,
+                );
+                metrics::stop_timer(timer);
+                Ok(Some(value))
+            }
+            None => {
+                metrics::stop_timer(timer);
+                Ok(None)
+            }
+        }
+    }
+
+    /// Return `true` if `key` exists in `column`.
+    pub fn key_exists(&self, col: DBColumn, key: &[u8]) -> Result<bool, Error> {
+        metrics::inc_counter_vec(&metrics::DISK_DB_EXISTS_COUNT, &[col.into()]);
+
+        let table_definition: TableDefinition<'_, &[u8], &[u8]> = TableDefinition::new(col.into());
+        let open_db = self.db.read();
+        let tx = open_db.begin_read()?;
+        let table = tx.open_table(table_definition)?;
+
+        table
+            .get(key)
+            .map_err(Into::into)
+            .map(|access_guard| access_guard.is_some())
+    }
+
+    /// Removes `key` from `column`.
+    pub fn key_delete(&self, col: DBColumn, key: &[u8]) -> Result<(), Error> {
+        let table_definition: TableDefinition<'_, &[u8], &[u8]> = TableDefinition::new(col.into());
+        let open_db = self.db.read();
+        let tx = open_db.begin_write()?;
+        let mut table = tx.open_table(table_definition)?;
+        metrics::inc_counter_vec(&metrics::DISK_DB_DELETE_COUNT, &[col.into()]);
+
+        table.remove(key).map(|_| ())?;
+        drop(table);
+        tx.commit().map_err(Into::into)
+    }
+
+    pub fn do_atomically(&self, ops_batch: Vec<KeyValueStoreOp>) -> Result<(), Error> {
+        let open_db = self.db.read();
+        let mut tx = open_db.begin_write()?;
+        tx.set_durability(self.write_options().into());
+        for op in ops_batch {
+            match op {
+                KeyValueStoreOp::PutKeyValue(column, key, value) => {
+                    let _timer = metrics::start_timer(&metrics::DISK_DB_WRITE_TIMES);
+                    metrics::inc_counter_vec_by(
+                        &metrics::DISK_DB_WRITE_BYTES,
+                        &[column.into()],
+                        value.len() as u64,
+                    );
+                    metrics::inc_counter_vec(&metrics::DISK_DB_WRITE_COUNT, &[column.into()]);
+                    let table_definition: TableDefinition<'_, &[u8], &[u8]> =
+                        TableDefinition::new(column.into());
+
+                    let mut table = tx.open_table(table_definition)?;
+                    table.insert(key.as_slice(), value.as_slice())?;
+                    drop(table);
+                }
+
+                KeyValueStoreOp::DeleteKey(column, key) => {
+                    metrics::inc_counter_vec(&metrics::DISK_DB_DELETE_COUNT, &[column.into()]);
+                    let _timer = metrics::start_timer(&metrics::DISK_DB_DELETE_TIMES);
+                    let table_definition: TableDefinition<'_, &[u8], &[u8]> =
+                        TableDefinition::new(column.into());
+
+                    let mut table = tx.open_table(table_definition)?;
+                    table.remove(key.as_slice())?;
+                    drop(table);
+                }
+            }
+        }
+
+        tx.commit()?;
+        Ok(())
+    }
+
+    /// Compact all values in the states and states flag columns.
+    pub fn compact(&self) -> Result<(), Error> {
+        let _timer = metrics::start_timer(&metrics::DISK_DB_COMPACT_TIMES);
+        let mut open_db = self.db.write();
+        let mut_db = open_db.borrow_mut();
+        mut_db.compact().map_err(Into::into).map(|_| ())
+    }
+
+    pub fn iter_column_keys_from<K: Key>(&self, column: DBColumn, from: &[u8]) -> ColumnKeyIter<K> {
+        let table_definition: TableDefinition<'_, &[u8], &[u8]> =
+            TableDefinition::new(column.into());
+
+        let result = (|| {
+            let open_db = self.db.read();
+            let read_txn = open_db.begin_read()?;
+            let table = read_txn.open_table(table_definition)?;
+            let range = table.range(from..)?;
+            Ok(range.map(move |res| {
+                let (key, _) = res?;
+                metrics::inc_counter_vec(&metrics::DISK_DB_KEY_READ_COUNT, &[column.into()]);
+                metrics::inc_counter_vec_by(
+                    &metrics::DISK_DB_KEY_READ_BYTES,
+                    &[column.into()],
+                    key.value().len() as u64,
+                );
+                K::from_bytes(key.value())
+            }))
+        })();
+
+        match result {
+            Ok(iter) => Box::new(iter),
+            Err(err) => Box::new(std::iter::once(Err(err))),
+        }
+    }
+
+    /// Iterate through all keys and values in a particular column.
+    pub fn iter_column_keys<K: Key>(&self, column: DBColumn) -> ColumnKeyIter<K> {
+        self.iter_column_keys_from(column, &vec![0; column.key_size()])
+    }
+
+    pub fn iter_column_from<K: Key>(&self, column: DBColumn, from: &[u8]) -> ColumnIter<K> {
+        let table_definition: TableDefinition<'_, &[u8], &[u8]> =
+            TableDefinition::new(column.into());
+
+        let result = (|| {
+            let open_db = self.db.read();
+            let read_txn = open_db.begin_read()?;
+            let table = read_txn.open_table(table_definition)?;
+            let range = table.range(from..)?;
+
+            Ok(range
+                .take_while(move |res| match res.as_ref() {
+                    Ok((_, _)) => true,
+                    Err(_) => false,
+                })
+                .map(move |res| {
+                    let (key, value) = res?;
+                    metrics::inc_counter_vec(&metrics::DISK_DB_READ_COUNT, &[column.into()]);
+                    metrics::inc_counter_vec_by(
+                        &metrics::DISK_DB_READ_BYTES,
+                        &[column.into()],
+                        value.value().len() as u64,
+                    );
+                    Ok((K::from_bytes(key.value())?, value.value().to_vec()))
+                }))
+        })();
+
+        match result {
+            Ok(iter) => Box::new(iter),
+            Err(err) => Box::new(std::iter::once(Err(err))),
+        }
+    }
+
+    pub fn iter_column<K: Key>(&self, column: DBColumn) -> ColumnIter<K> {
+        self.iter_column_from(column, &vec![0; column.key_size()])
+    }
+
+    pub fn delete_batch(&self, col: DBColumn, ops: HashSet<&[u8]>) -> Result<(), Error> {
+        let open_db = self.db.read();
+        let mut tx = open_db.begin_write()?;
+
+        tx.set_durability(redb::Durability::None);
+
+        let table_definition: TableDefinition<'_, &[u8], &[u8]> = TableDefinition::new(col.into());
+
+        let mut table = tx.open_table(table_definition)?;
+        table.retain(|key, _| !ops.contains(key))?;
+
+        drop(table);
+        tx.commit()?;
+        Ok(())
+    }
+
+    pub fn delete_if(
+        &self,
+        column: DBColumn,
+        mut f: impl FnMut(&[u8]) -> Result<bool, Error>,
+    ) -> Result<(), Error> {
+        let open_db = self.db.read();
+        let mut tx = open_db.begin_write()?;
+
+        tx.set_durability(redb::Durability::None);
+
+        let table_definition: TableDefinition<'_, &[u8], &[u8]> =
+            TableDefinition::new(column.into());
+
+        let mut table = tx.open_table(table_definition)?;
+        table.retain(|_, value| !f(value).unwrap_or(false))?;
+
+        drop(table);
+        tx.commit()?;
+        Ok(())
+    }
+}
diff --git a/beacon_node/store/src/errors.rs b/beacon_node/store/src/errors.rs
index 6bb4edee6b..41fd17ef43 100644
--- a/beacon_node/store/src/errors.rs
+++ b/beacon_node/store/src/errors.rs
@@ -2,6 +2,8 @@ use crate::chunked_vector::ChunkError;
 use crate::config::StoreConfigError;
 use crate::hot_cold_store::HotColdDBError;
 use crate::{hdiff, DBColumn};
+#[cfg(feature = "leveldb")]
+use leveldb::error::Error as LevelDBError;
 use ssz::DecodeError;
 use state_processing::BlockReplayError;
 use types::{milhouse, BeaconStateError, EpochCacheError, Hash256, InconsistentFork, Slot};
@@ -48,6 +50,16 @@ pub enum Error {
     MissingGenesisState,
     MissingSnapshot(Slot),
     BlockReplayError(BlockReplayError),
+    AddPayloadLogicError,
+    InvalidKey,
+    InvalidBytes,
+    InconsistentFork(InconsistentFork),
+    #[cfg(feature = "leveldb")]
+    LevelDbError(LevelDBError),
+    #[cfg(feature = "redb")]
+    RedbError(redb::Error),
+    CacheBuildError(EpochCacheError),
+    RandaoMixOutOfBounds,
     MilhouseError(milhouse::Error),
     Compression(std::io::Error),
     FinalizedStateDecreasingSlot,
@@ -56,17 +68,11 @@ pub enum Error {
         state_root: Hash256,
         slot: Slot,
     },
-    AddPayloadLogicError,
-    InvalidKey,
-    InvalidBytes,
-    InconsistentFork(InconsistentFork),
     Hdiff(hdiff::Error),
-    CacheBuildError(EpochCacheError),
     ForwardsIterInvalidColumn(DBColumn),
     ForwardsIterGap(DBColumn, Slot, Slot),
     StateShouldNotBeRequired(Slot),
     MissingBlock(Hash256),
-    RandaoMixOutOfBounds,
     GenesisStateUnknown,
     ArithError(safe_arith::ArithError),
 }
@@ -145,6 +151,62 @@ impl From<InconsistentFork> for Error {
     }
 }
 
+#[cfg(feature = "leveldb")]
+impl From<LevelDBError> for Error {
+    fn from(e: LevelDBError) -> Error {
+        Error::LevelDbError(e)
+    }
+}
+
+#[cfg(feature = "redb")]
+impl From<redb::Error> for Error {
+    fn from(e: redb::Error) -> Self {
+        Error::RedbError(e)
+    }
+}
+
+#[cfg(feature = "redb")]
+impl From<redb::TableError> for Error {
+    fn from(e: redb::TableError) -> Self {
+        Error::RedbError(e.into())
+    }
+}
+
+#[cfg(feature = "redb")]
+impl From<redb::TransactionError> for Error {
+    fn from(e: redb::TransactionError) -> Self {
+        Error::RedbError(e.into())
+    }
+}
+
+#[cfg(feature = "redb")]
+impl From<redb::DatabaseError> for Error {
+    fn from(e: redb::DatabaseError) -> Self {
+        Error::RedbError(e.into())
+    }
+}
+
+#[cfg(feature = "redb")]
+impl From<redb::StorageError> for Error {
+    fn from(e: redb::StorageError) -> Self {
+        Error::RedbError(e.into())
+    }
+}
+
+#[cfg(feature = "redb")]
+impl From<redb::CommitError> for Error {
+    fn from(e: redb::CommitError) -> Self {
+        Error::RedbError(e.into())
+    }
+}
+
+#[cfg(feature = "redb")]
+impl From<redb::CompactionError> for Error {
+    fn from(e: redb::CompactionError) -> Self {
+        Error::RedbError(e.into())
+    }
+}
+
 impl From<EpochCacheError> for Error {
     fn from(e: EpochCacheError) -> Error {
         Error::CacheBuildError(e)
diff --git a/beacon_node/store/src/forwards_iter.rs b/beacon_node/store/src/forwards_iter.rs
index 27769a310a..255b7d8eac 100644
--- a/beacon_node/store/src/forwards_iter.rs
+++ b/beacon_node/store/src/forwards_iter.rs
@@ -4,7 +4,6 @@ use crate::{ColumnIter, DBColumn, HotColdDB, ItemStore};
 use itertools::process_results;
 use std::marker::PhantomData;
 use types::{BeaconState, EthSpec, Hash256, Slot};
-
 pub type HybridForwardsBlockRootsIterator<'a, E, Hot, Cold> =
     HybridForwardsIterator<'a, E, Hot, Cold>;
 pub type HybridForwardsStateRootsIterator<'a, E, Hot, Cold> =
@@ -159,6 +158,7 @@ impl<E: EthSpec, Hot: ItemStore<E>, Cold: ItemStore<E>> Iterator
             return None;
         }
         self.inner
+            .as_mut()
             .next()?
             .and_then(|(slot_bytes, root_bytes)| {
                 let slot = slot_bytes
@@ -265,7 +265,7 @@ impl<'a, E: EthSpec, Hot: ItemStore<E>, Cold: ItemStore<E>>
                 // `end_slot`. If it tries to continue further a `NoContinuationData` error will be
                 // returned.
                 let continuation_data =
-                    if end_slot.map_or(false, |end_slot| end_slot < freezer_upper_bound) {
+                    if end_slot.is_some_and(|end_slot| end_slot < freezer_upper_bound) {
                         None
                     } else {
                         Some(Box::new(get_state()?))
@@ -306,7 +306,7 @@ impl<'a, E: EthSpec, Hot: ItemStore<E>, Cold: ItemStore<E>>
                     None => {
                         // If the iterator has an end slot (inclusive) which has already been
                         // covered by the (exclusive) frozen forwards iterator, then we're done!
-                        if end_slot.map_or(false, |end_slot| iter.end_slot == end_slot + 1) {
+                        if end_slot.is_some_and(|end_slot| iter.end_slot == end_slot + 1) {
                             *self = Finished;
                             return Ok(None);
                         }
diff --git a/beacon_node/store/src/garbage_collection.rs b/beacon_node/store/src/garbage_collection.rs
index 5f8ed8f5e7..06393f2d21 100644
--- a/beacon_node/store/src/garbage_collection.rs
+++ b/beacon_node/store/src/garbage_collection.rs
@@ -1,10 +1,11 @@
 //! Garbage collection process that runs at start-up to clean up the database.
+use crate::database::interface::BeaconNodeBackend;
 use crate::hot_cold_store::HotColdDB;
-use crate::{Error, LevelDB, StoreOp};
+use crate::{DBColumn, Error};
 use slog::debug;
 use types::EthSpec;
 
-impl<E> HotColdDB<E, LevelDB<E>, LevelDB<E>>
+impl<E> HotColdDB<E, BeaconNodeBackend<E>, BeaconNodeBackend<E>>
 where
     E: EthSpec,
 {
@@ -16,21 +17,22 @@ where
 
     /// Delete the temporary states that were leftover by failed block imports.
     pub fn delete_temp_states(&self) -> Result<(), Error> {
-        let delete_ops =
-            self.iter_temporary_state_roots()
-                .try_fold(vec![], |mut ops, state_root| {
-                    let state_root = state_root?;
-                    ops.push(StoreOp::DeleteState(state_root, None));
-                    Result::<_, Error>::Ok(ops)
-                })?;
-
-        if !delete_ops.is_empty() {
+        let mut ops = vec![];
+        self.iter_temporary_state_roots().for_each(|state_root| {
+            if let Ok(state_root) = state_root {
+                ops.push(state_root);
+            }
+        });
+        if !ops.is_empty() {
             debug!(
                 self.log,
                 "Garbage collecting {} temporary states",
-                delete_ops.len()
+                ops.len()
             );
-            self.do_atomically_with_block_and_blobs_cache(delete_ops)?;
+
+            self.delete_batch(DBColumn::BeaconState, ops.clone())?;
+            self.delete_batch(DBColumn::BeaconStateSummary, ops.clone())?;
+            self.delete_batch(DBColumn::BeaconStateTemporary, ops)?;
         }
 
         Ok(())
diff --git a/beacon_node/store/src/hot_cold_store.rs b/beacon_node/store/src/hot_cold_store.rs
index da3e6d4ebc..134be9ec0d 100644
--- a/beacon_node/store/src/hot_cold_store.rs
+++ b/beacon_node/store/src/hot_cold_store.rs
@@ -1,10 +1,10 @@
 use crate::config::{OnDiskStoreConfig, StoreConfig};
+use crate::database::interface::BeaconNodeBackend;
 use crate::forwards_iter::{HybridForwardsBlockRootsIterator, HybridForwardsStateRootsIterator};
 use crate::hdiff::{HDiff, HDiffBuffer, HierarchyModuli, StorageStrategy};
 use crate::historic_state_cache::HistoricStateCache;
 use crate::impls::beacon_state::{get_full_state, store_full_state};
 use crate::iter::{BlockRootsIterator, ParentRootBlockIterator, RootsIterator};
-use crate::leveldb_store::{BytesKey, LevelDB};
 use crate::memory_store::MemoryStore;
 use crate::metadata::{
     AnchorInfo, BlobInfo, CompactionTimestamp, DataColumnInfo, PruningCheckpoint, SchemaVersion,
@@ -14,12 +14,10 @@ use crate::metadata::{
 };
 use crate::state_cache::{PutStateOutcome, StateCache};
 use crate::{
-    get_data_column_key, get_key_for_col, DBColumn, DatabaseBlock, Error, ItemStore,
-    KeyValueStoreOp, StoreItem, StoreOp,
+    get_data_column_key, metrics, parse_data_column_key, BlobSidecarListFromRoot, ColumnKeyIter,
+    DBColumn, DatabaseBlock, Error, ItemStore, KeyValueStore, KeyValueStoreOp, StoreItem, StoreOp,
 };
-use crate::{metrics, parse_data_column_key};
 use itertools::{process_results, Itertools};
-use leveldb::iterator::LevelDBIterator;
 use lru::LruCache;
 use parking_lot::{Mutex, RwLock};
 use safe_arith::SafeArith;
@@ -121,6 +119,11 @@ impl<E: EthSpec> BlockCache<E> {
     pub fn get_blobs<'a>(&'a mut self, block_root: &Hash256) -> Option<&'a BlobSidecarList<E>> {
         self.blob_cache.get(block_root)
     }
+    pub fn get_data_columns(&mut self, block_root: &Hash256) -> Option<DataColumnSidecarList<E>> {
+        self.data_column_cache
+            .get(block_root)
+            .map(|map| map.values().cloned().collect::<Vec<_>>())
+    }
     pub fn get_data_column<'a>(
         &'a mut self,
         block_root: &Hash256,
@@ -231,7 +234,7 @@ impl<E: EthSpec> HotColdDB<E, MemoryStore<E>, MemoryStore<E>> {
     }
 }
 
-impl<E: EthSpec> HotColdDB<E, LevelDB<E>, LevelDB<E>> {
+impl<E: EthSpec> HotColdDB<E, BeaconNodeBackend<E>, BeaconNodeBackend<E>> {
     /// Open a new or existing database, with the given paths to the hot and cold DBs.
     ///
     /// The `migrate_schema` function is passed in so that the parent `BeaconChain` can provide
@@ -249,7 +252,7 @@ impl<E: EthSpec> HotColdDB<E, LevelDB<E>, LevelDB<E>> {
 
         let hierarchy = config.hierarchy_config.to_moduli()?;
 
-        let hot_db = LevelDB::open(hot_path)?;
+        let hot_db = BeaconNodeBackend::open(&config, hot_path)?;
         let anchor_info = RwLock::new(Self::load_anchor_info(&hot_db)?);
 
         let db = HotColdDB {
@@ -257,8 +260,8 @@ impl<E: EthSpec> HotColdDB<E, LevelDB<E>, LevelDB<E>> {
             anchor_info,
             blob_info: RwLock::new(BlobInfo::default()),
             data_column_info: RwLock::new(DataColumnInfo::default()),
-            cold_db: LevelDB::open(cold_path)?,
-            blobs_db: LevelDB::open(blobs_db_path)?,
+            blobs_db: BeaconNodeBackend::open(&config, blobs_db_path)?,
+            cold_db: BeaconNodeBackend::open(&config, cold_path)?,
             hot_db,
             block_cache: Mutex::new(BlockCache::new(config.block_cache_size)),
             state_cache: Mutex::new(StateCache::new(config.state_cache_size)),
@@ -324,16 +327,15 @@ impl<E: EthSpec> HotColdDB<E, LevelDB<E>, LevelDB<E>> {
         db.compare_and_set_blob_info_with_write(<_>::default(), new_blob_info.clone())?;
 
         let data_column_info = db.load_data_column_info()?;
-        let eip7594_fork_slot = db
+        let fulu_fork_slot = db
             .spec
-            .eip7594_fork_epoch
+            .fulu_fork_epoch
             .map(|epoch| epoch.start_slot(E::slots_per_epoch()));
         let new_data_column_info = match &data_column_info {
             Some(data_column_info) => {
                 // Set the oldest data column slot to the fork slot if it is not yet set.
-                let oldest_data_column_slot = data_column_info
-                    .oldest_data_column_slot
-                    .or(eip7594_fork_slot);
+                let oldest_data_column_slot =
+                    data_column_info.oldest_data_column_slot.or(fulu_fork_slot);
                 DataColumnInfo {
                     oldest_data_column_slot,
                 }
@@ -341,7 +343,7 @@ impl<E: EthSpec> HotColdDB<E, LevelDB<E>, LevelDB<E>> {
             // First start.
             None => DataColumnInfo {
                 // Set the oldest data column slot to the fork slot if it is not yet set.
-                oldest_data_column_slot: eip7594_fork_slot,
+                oldest_data_column_slot: fulu_fork_slot,
             },
         };
         db.compare_and_set_data_column_info_with_write(
@@ -407,24 +409,9 @@ impl<E: EthSpec> HotColdDB<E, LevelDB<E>, LevelDB<E>> {
     }
 
     /// Return an iterator over the state roots of all temporary states.
-    pub fn iter_temporary_state_roots(&self) -> impl Iterator<Item = Result<Hash256, Error>> + '_ {
-        let column = DBColumn::BeaconStateTemporary;
-        let start_key =
-            BytesKey::from_vec(get_key_for_col(column.into(), Hash256::zero().as_slice()));
-
-        let keys_iter = self.hot_db.keys_iter();
-        keys_iter.seek(&start_key);
-
-        keys_iter
-            .take_while(move |key| key.matches_column(column))
-            .map(move |bytes_key| {
-                bytes_key.remove_column(column).ok_or_else(|| {
-                    HotColdDBError::IterationError {
-                        unexpected_key: bytes_key,
-                    }
-                    .into()
-                })
-            })
+    pub fn iter_temporary_state_roots(&self) -> ColumnKeyIter<Hash256> {
+        self.hot_db
+            .iter_column_keys::<Hash256>(DBColumn::BeaconStateTemporary)
     }
 }
 
@@ -536,9 +523,9 @@ impl<E: EthSpec, Hot: ItemStore<E>, Cold: ItemStore<E>> HotColdDB<E, Hot, Cold>
         blinded_block: &SignedBeaconBlock<E, BlindedPayload<E>>,
         ops: &mut Vec<KeyValueStoreOp>,
     ) {
-        let db_key = get_key_for_col(DBColumn::BeaconBlock.into(), key.as_slice());
         ops.push(KeyValueStoreOp::PutKeyValue(
-            db_key,
+            DBColumn::BeaconBlock,
+            key.as_slice().into(),
             blinded_block.as_ssz_bytes(),
         ));
     }
@@ -660,7 +647,7 @@ impl<E: EthSpec, Hot: ItemStore<E>, Cold: ItemStore<E>> HotColdDB<E, Hot, Cold>
         decoder: impl FnOnce(&[u8]) -> Result<SignedBeaconBlock<E, Payload>, ssz::DecodeError>,
     ) -> Result<Option<SignedBeaconBlock<E, Payload>>, Error> {
         self.hot_db
-            .get_bytes(DBColumn::BeaconBlock.into(), block_root.as_slice())?
+            .get_bytes(DBColumn::BeaconBlock, block_root.as_slice())?
             .map(|block_bytes| decoder(&block_bytes))
             .transpose()
             .map_err(|e| e.into())
@@ -673,10 +660,12 @@ impl<E: EthSpec, Hot: ItemStore<E>, Cold: ItemStore<E>> HotColdDB<E, Hot, Cold>
         block_root: &Hash256,
         fork_name: ForkName,
     ) -> Result<Option<ExecutionPayload<E>>, Error> {
-        let column = ExecutionPayload::<E>::db_column().into();
         let key = block_root.as_slice();
 
-        match self.hot_db.get_bytes(column, key)? {
+        match self
+            .hot_db
+            .get_bytes(ExecutionPayload::<E>::db_column(), key)?
+        {
             Some(bytes) => Ok(Some(ExecutionPayload::from_ssz_bytes(&bytes, fork_name)?)),
             None => Ok(None),
         }
@@ -705,10 +694,7 @@ impl<E: EthSpec, Hot: ItemStore<E>, Cold: ItemStore<E>> HotColdDB<E, Hot, Cold>
     ) -> Result<Option<MerkleProof>, Error> {
         let column = DBColumn::SyncCommitteeBranch;
 
-        if let Some(bytes) = self
-            .hot_db
-            .get_bytes(column.into(), &block_root.as_ssz_bytes())?
-        {
+        if let Some(bytes) = self.hot_db.get_bytes(column, &block_root.as_ssz_bytes())? {
             let sync_committee_branch = Vec::<Hash256>::from_ssz_bytes(&bytes)?;
             return Ok(Some(sync_committee_branch));
         }
@@ -725,7 +711,7 @@ impl<E: EthSpec, Hot: ItemStore<E>, Cold: ItemStore<E>> HotColdDB<E, Hot, Cold>
 
         if let Some(bytes) = self
             .hot_db
-            .get_bytes(column.into(), &sync_committee_period.as_ssz_bytes())?
+            .get_bytes(column, &sync_committee_period.as_ssz_bytes())?
         {
             let sync_committee: SyncCommittee<E> = SyncCommittee::from_ssz_bytes(&bytes)?;
             return Ok(Some(sync_committee));
@@ -741,7 +727,7 @@ impl<E: EthSpec, Hot: ItemStore<E>, Cold: ItemStore<E>> HotColdDB<E, Hot, Cold>
     ) -> Result<(), Error> {
         let column = DBColumn::SyncCommitteeBranch;
         self.hot_db.put_bytes(
-            column.into(),
+            column,
             &block_root.as_ssz_bytes(),
             &sync_committee_branch.as_ssz_bytes(),
         )?;
@@ -755,7 +741,7 @@ impl<E: EthSpec, Hot: ItemStore<E>, Cold: ItemStore<E>> HotColdDB<E, Hot, Cold>
     ) -> Result<(), Error> {
         let column = DBColumn::SyncCommittee;
         self.hot_db.put_bytes(
-            column.into(),
+            column,
             &sync_committee_period.to_le_bytes(),
             &sync_committee.as_ssz_bytes(),
         )?;
@@ -767,10 +753,10 @@ impl<E: EthSpec, Hot: ItemStore<E>, Cold: ItemStore<E>> HotColdDB<E, Hot, Cold>
         &self,
         sync_committee_period: u64,
     ) -> Result<Option<LightClientUpdate<E>>, Error> {
-        let column = DBColumn::LightClientUpdate;
-        let res = self
-            .hot_db
-            .get_bytes(column.into(), &sync_committee_period.to_le_bytes())?;
+        let res = self.hot_db.get_bytes(
+            DBColumn::LightClientUpdate,
+            &sync_committee_period.to_le_bytes(),
+        )?;
 
         if let Some(light_client_update_bytes) = res {
             let epoch = sync_committee_period
@@ -822,10 +808,8 @@ impl<E: EthSpec, Hot: ItemStore<E>, Cold: ItemStore<E>> HotColdDB<E, Hot, Cold>
         sync_committee_period: u64,
         light_client_update: &LightClientUpdate<E>,
     ) -> Result<(), Error> {
-        let column = DBColumn::LightClientUpdate;
-
         self.hot_db.put_bytes(
-            column.into(),
+            DBColumn::LightClientUpdate,
             &sync_committee_period.to_le_bytes(),
             &light_client_update.as_ssz_bytes(),
         )?;
@@ -836,29 +820,29 @@ impl<E: EthSpec, Hot: ItemStore<E>, Cold: ItemStore<E>> HotColdDB<E, Hot, Cold>
     /// Check if the blobs for a block exists on disk.
     pub fn blobs_exist(&self, block_root: &Hash256) -> Result<bool, Error> {
         self.blobs_db
-            .key_exists(DBColumn::BeaconBlob.into(), block_root.as_slice())
+            .key_exists(DBColumn::BeaconBlob, block_root.as_slice())
     }
 
     /// Determine whether a block exists in the database.
     pub fn block_exists(&self, block_root: &Hash256) -> Result<bool, Error> {
         self.hot_db
-            .key_exists(DBColumn::BeaconBlock.into(), block_root.as_slice())
+            .key_exists(DBColumn::BeaconBlock, block_root.as_slice())
     }
 
     /// Delete a block from the store and the block cache.
     pub fn delete_block(&self, block_root: &Hash256) -> Result<(), Error> {
         self.block_cache.lock().delete(block_root);
         self.hot_db
-            .key_delete(DBColumn::BeaconBlock.into(), block_root.as_slice())?;
+            .key_delete(DBColumn::BeaconBlock, block_root.as_slice())?;
         self.hot_db
-            .key_delete(DBColumn::ExecPayload.into(), block_root.as_slice())?;
+            .key_delete(DBColumn::ExecPayload, block_root.as_slice())?;
         self.blobs_db
-            .key_delete(DBColumn::BeaconBlob.into(), block_root.as_slice())
+            .key_delete(DBColumn::BeaconBlob, block_root.as_slice())
     }
 
     pub fn put_blobs(&self, block_root: &Hash256, blobs: BlobSidecarList<E>) -> Result<(), Error> {
         self.blobs_db.put_bytes(
-            DBColumn::BeaconBlob.into(),
+            DBColumn::BeaconBlob,
             block_root.as_slice(),
             &blobs.as_ssz_bytes(),
         )?;
@@ -872,8 +856,29 @@ impl<E: EthSpec, Hot: ItemStore<E>, Cold: ItemStore<E>> HotColdDB<E, Hot, Cold>
         blobs: BlobSidecarList<E>,
         ops: &mut Vec<KeyValueStoreOp>,
     ) {
-        let db_key = get_key_for_col(DBColumn::BeaconBlob.into(), key.as_slice());
-        ops.push(KeyValueStoreOp::PutKeyValue(db_key, blobs.as_ssz_bytes()));
+        ops.push(KeyValueStoreOp::PutKeyValue(
+            DBColumn::BeaconBlob,
+            key.as_slice().to_vec(),
+            blobs.as_ssz_bytes(),
+        ));
+    }
+
+    pub fn put_data_columns(
+        &self,
+        block_root: &Hash256,
+        data_columns: DataColumnSidecarList<E>,
+    ) -> Result<(), Error> {
+        for data_column in data_columns {
+            self.blobs_db.put_bytes(
+                DBColumn::BeaconDataColumn,
+                &get_data_column_key(block_root, &data_column.index),
+                &data_column.as_ssz_bytes(),
+            )?;
+            self.block_cache
+                .lock()
+                .put_data_column(*block_root, data_column);
+        }
+        Ok(())
     }
 
     pub fn data_columns_as_kv_store_ops(
@@ -883,12 +888,9 @@ impl<E: EthSpec, Hot: ItemStore<E>, Cold: ItemStore<E>> HotColdDB<E, Hot, Cold>
         ops: &mut Vec<KeyValueStoreOp>,
     ) {
         for data_column in data_columns {
-            let db_key = get_key_for_col(
-                DBColumn::BeaconDataColumn.into(),
-                &get_data_column_key(block_root, &data_column.index),
-            );
             ops.push(KeyValueStoreOp::PutKeyValue(
-                db_key,
+                DBColumn::BeaconDataColumn,
+                get_data_column_key(block_root, &data_column.index),
                 data_column.as_ssz_bytes(),
             ));
         }
@@ -1202,63 +1204,68 @@ impl<E: EthSpec, Hot: ItemStore<E>, Cold: ItemStore<E>> HotColdDB<E, Hot, Cold>
                 }
 
                 StoreOp::DeleteStateTemporaryFlag(state_root) => {
-                    let db_key =
-                        get_key_for_col(TemporaryFlag::db_column().into(), state_root.as_slice());
-                    key_value_batch.push(KeyValueStoreOp::DeleteKey(db_key));
+                    key_value_batch.push(KeyValueStoreOp::DeleteKey(
+                        TemporaryFlag::db_column(),
+                        state_root.as_slice().to_vec(),
+                    ));
                 }
 
                 StoreOp::DeleteBlock(block_root) => {
-                    let key = get_key_for_col(DBColumn::BeaconBlock.into(), block_root.as_slice());
-                    key_value_batch.push(KeyValueStoreOp::DeleteKey(key));
+                    key_value_batch.push(KeyValueStoreOp::DeleteKey(
+                        DBColumn::BeaconBlock,
+                        block_root.as_slice().to_vec(),
+                    ));
                 }
 
                 StoreOp::DeleteBlobs(block_root) => {
-                    let key = get_key_for_col(DBColumn::BeaconBlob.into(), block_root.as_slice());
-                    key_value_batch.push(KeyValueStoreOp::DeleteKey(key));
+                    key_value_batch.push(KeyValueStoreOp::DeleteKey(
+                        DBColumn::BeaconBlob,
+                        block_root.as_slice().to_vec(),
+                    ));
                 }
 
                 StoreOp::DeleteDataColumns(block_root, column_indices) => {
                     for index in column_indices {
-                        let key = get_key_for_col(
-                            DBColumn::BeaconDataColumn.into(),
-                            &get_data_column_key(&block_root, &index),
-                        );
-                        key_value_batch.push(KeyValueStoreOp::DeleteKey(key));
+                        let key = get_data_column_key(&block_root, &index);
+                        key_value_batch
+                            .push(KeyValueStoreOp::DeleteKey(DBColumn::BeaconDataColumn, key));
                     }
                 }
 
                 StoreOp::DeleteState(state_root, slot) => {
                     // Delete the hot state summary.
-                    let state_summary_key =
-                        get_key_for_col(DBColumn::BeaconStateSummary.into(), state_root.as_slice());
-                    key_value_batch.push(KeyValueStoreOp::DeleteKey(state_summary_key));
+                    key_value_batch.push(KeyValueStoreOp::DeleteKey(
+                        DBColumn::BeaconStateSummary,
+                        state_root.as_slice().to_vec(),
+                    ));
 
                     // Delete the state temporary flag (if any). Temporary flags are commonly
                     // created by the state advance routine.
-                    let state_temp_key = get_key_for_col(
-                        DBColumn::BeaconStateTemporary.into(),
-                        state_root.as_slice(),
-                    );
-                    key_value_batch.push(KeyValueStoreOp::DeleteKey(state_temp_key));
+                    key_value_batch.push(KeyValueStoreOp::DeleteKey(
+                        DBColumn::BeaconStateTemporary,
+                        state_root.as_slice().to_vec(),
+                    ));
 
                     if slot.map_or(true, |slot| slot % E::slots_per_epoch() == 0) {
-                        let state_key =
-                            get_key_for_col(DBColumn::BeaconState.into(), state_root.as_slice());
-                        key_value_batch.push(KeyValueStoreOp::DeleteKey(state_key));
+                        key_value_batch.push(KeyValueStoreOp::DeleteKey(
+                            DBColumn::BeaconState,
+                            state_root.as_slice().to_vec(),
+                        ));
                     }
                 }
 
                 StoreOp::DeleteExecutionPayload(block_root) => {
-                    let key = get_key_for_col(DBColumn::ExecPayload.into(), block_root.as_slice());
-                    key_value_batch.push(KeyValueStoreOp::DeleteKey(key));
+                    key_value_batch.push(KeyValueStoreOp::DeleteKey(
+                        DBColumn::ExecPayload,
+                        block_root.as_slice().to_vec(),
+                    ));
                 }
 
                 StoreOp::DeleteSyncCommitteeBranch(block_root) => {
-                    let key = get_key_for_col(
-                        DBColumn::SyncCommitteeBranch.into(),
-                        block_root.as_slice(),
-                    );
-                    key_value_batch.push(KeyValueStoreOp::DeleteKey(key));
+                    key_value_batch.push(KeyValueStoreOp::DeleteKey(
+                        DBColumn::SyncCommitteeBranch,
+                        block_root.as_slice().to_vec(),
+                    ));
                 }
 
                 StoreOp::KeyValueOp(kv_op) => {
@@ -1269,6 +1276,19 @@ impl<E: EthSpec, Hot: ItemStore<E>, Cold: ItemStore<E>> HotColdDB<E, Hot, Cold>
         Ok(key_value_batch)
     }
 
+    pub fn delete_batch(&self, col: DBColumn, ops: Vec<Hash256>) -> Result<(), Error> {
+        let new_ops: HashSet<&[u8]> = ops.iter().map(|v| v.as_slice()).collect();
+        self.hot_db.delete_batch(col, new_ops)
+    }
+
+    pub fn delete_if(
+        &self,
+        column: DBColumn,
+        f: impl Fn(&[u8]) -> Result<bool, Error>,
+    ) -> Result<(), Error> {
+        self.hot_db.delete_if(column, f)
+    }
+
     pub fn do_atomically_with_block_and_blobs_cache(
         &self,
         batch: Vec<StoreOp<E>>,
@@ -1280,9 +1300,10 @@ impl<E: EthSpec, Hot: ItemStore<E>, Cold: ItemStore<E>> HotColdDB<E, Hot, Cold>
                 StoreOp::PutBlobs(_, _) | StoreOp::PutDataColumns(_, _) => true,
                 StoreOp::DeleteBlobs(block_root) => {
                     match self.get_blobs(block_root) {
-                        Ok(Some(blob_sidecar_list)) => {
+                        Ok(BlobSidecarListFromRoot::Blobs(blob_sidecar_list)) => {
                             blobs_to_delete.push((*block_root, blob_sidecar_list));
                         }
+                        Ok(BlobSidecarListFromRoot::NoBlobs | BlobSidecarListFromRoot::NoRoot) => {}
                         Err(e) => {
                             error!(
                                 self.log, "Error getting blobs";
@@ -1290,7 +1311,6 @@ impl<E: EthSpec, Hot: ItemStore<E>, Cold: ItemStore<E>> HotColdDB<E, Hot, Cold>
                                 "error" => ?e
                             );
                         }
-                        _ => (),
                     }
                     true
                 }
@@ -1608,10 +1628,8 @@ impl<E: EthSpec, Hot: ItemStore<E>, Cold: ItemStore<E>> HotColdDB<E, Hot, Cold>
     ) -> Result<(), Error> {
         ops.push(ColdStateSummary { slot }.as_kv_store_op(*state_root));
         ops.push(KeyValueStoreOp::PutKeyValue(
-            get_key_for_col(
-                DBColumn::BeaconStateRoots.into(),
-                &slot.as_u64().to_be_bytes(),
-            ),
+            DBColumn::BeaconStateRoots,
+            slot.as_u64().to_be_bytes().to_vec(),
             state_root.as_slice().to_vec(),
         ));
         Ok(())
@@ -1678,19 +1696,19 @@ impl<E: EthSpec, Hot: ItemStore<E>, Cold: ItemStore<E>> HotColdDB<E, Hot, Cold>
             out
         };
 
-        let key = get_key_for_col(
-            DBColumn::BeaconStateSnapshot.into(),
-            &state.slot().as_u64().to_be_bytes(),
-        );
-        ops.push(KeyValueStoreOp::PutKeyValue(key, compressed_value));
+        ops.push(KeyValueStoreOp::PutKeyValue(
+            DBColumn::BeaconStateSnapshot,
+            state.slot().as_u64().to_be_bytes().to_vec(),
+            compressed_value,
+        ));
         Ok(())
     }
 
     fn load_cold_state_bytes_as_snapshot(&self, slot: Slot) -> Result<Option<Vec<u8>>, Error> {
-        match self.cold_db.get_bytes(
-            DBColumn::BeaconStateSnapshot.into(),
-            &slot.as_u64().to_be_bytes(),
-        )? {
+        match self
+            .cold_db
+            .get_bytes(DBColumn::BeaconStateSnapshot, &slot.as_u64().to_be_bytes())?
+        {
             Some(bytes) => {
                 let _timer =
                     metrics::start_timer(&metrics::STORE_BEACON_STATE_FREEZER_DECOMPRESS_TIME);
@@ -1731,11 +1749,11 @@ impl<E: EthSpec, Hot: ItemStore<E>, Cold: ItemStore<E>> HotColdDB<E, Hot, Cold>
         };
         let diff_bytes = diff.as_ssz_bytes();
 
-        let key = get_key_for_col(
-            DBColumn::BeaconStateDiff.into(),
-            &state.slot().as_u64().to_be_bytes(),
-        );
-        ops.push(KeyValueStoreOp::PutKeyValue(key, diff_bytes));
+        ops.push(KeyValueStoreOp::PutKeyValue(
+            DBColumn::BeaconStateDiff,
+            state.slot().as_u64().to_be_bytes().to_vec(),
+            diff_bytes,
+        ));
         Ok(())
     }
 
@@ -1858,10 +1876,7 @@ impl<E: EthSpec, Hot: ItemStore<E>, Cold: ItemStore<E>> HotColdDB<E, Hot, Cold>
         let bytes = {
             let _t = metrics::start_timer(&metrics::BEACON_HDIFF_READ_TIMES);
             self.cold_db
-                .get_bytes(
-                    DBColumn::BeaconStateDiff.into(),
-                    &slot.as_u64().to_be_bytes(),
-                )?
+                .get_bytes(DBColumn::BeaconStateDiff, &slot.as_u64().to_be_bytes())?
                 .ok_or(HotColdDBError::MissingHDiff(slot))?
         };
         let hdiff = {
@@ -2044,34 +2059,86 @@ impl<E: EthSpec, Hot: ItemStore<E>, Cold: ItemStore<E>> HotColdDB<E, Hot, Cold>
             })
     }
 
+    /// Fetch columns for a given block from the store.
+    pub fn get_data_columns(
+        &self,
+        block_root: &Hash256,
+    ) -> Result<Option<DataColumnSidecarList<E>>, Error> {
+        if let Some(columns) = self.block_cache.lock().get_data_columns(block_root) {
+            metrics::inc_counter(&metrics::BEACON_DATA_COLUMNS_CACHE_HIT_COUNT);
+            return Ok(Some(columns));
+        }
+
+        let columns = self
+            .blobs_db
+            .iter_column_from::<Vec<u8>>(DBColumn::BeaconDataColumn, block_root.as_slice())
+            .take_while(|res| {
+                res.as_ref()
+                    .is_ok_and(|(key, _)| key.starts_with(block_root.as_slice()))
+            })
+            .map(|result| {
+                let (_key, value) = result?;
+                let column = DataColumnSidecar::<E>::from_ssz_bytes(&value).map(Arc::new)?;
+                self.block_cache
+                    .lock()
+                    .put_data_column(*block_root, column.clone());
+                Ok(column)
+            })
+            .collect::<Result<DataColumnSidecarList<E>, Error>>()?;
+
+        if columns.is_empty() {
+            Ok(None)
+        } else {
+            Ok(Some(columns))
+        }
+    }
+
     /// Fetch blobs for a given block from the store.
-    pub fn get_blobs(&self, block_root: &Hash256) -> Result<Option<BlobSidecarList<E>>, Error> {
+    pub fn get_blobs(&self, block_root: &Hash256) -> Result<BlobSidecarListFromRoot<E>, Error> {
         // Check the cache.
         if let Some(blobs) = self.block_cache.lock().get_blobs(block_root) {
             metrics::inc_counter(&metrics::BEACON_BLOBS_CACHE_HIT_COUNT);
-            return Ok(Some(blobs.clone()));
+            return Ok(blobs.clone().into());
         }
 
         match self
             .blobs_db
-            .get_bytes(DBColumn::BeaconBlob.into(), block_root.as_slice())?
+            .get_bytes(DBColumn::BeaconBlob, block_root.as_slice())?
         {
             Some(ref blobs_bytes) => {
-                let blobs = BlobSidecarList::from_ssz_bytes(blobs_bytes)?;
-                self.block_cache
-                    .lock()
-                    .put_blobs(*block_root, blobs.clone());
-                Ok(Some(blobs))
+                // We insert a VariableList of BlobSidecars into the db, but retrieve
+                // a plain vec since we don't know the length limit of the list without
+                // knowing the slot.
+                // The encoding of a VariableList is the same as a regular vec.
+                let blobs: Vec<Arc<BlobSidecar<E>>> = Vec::<_>::from_ssz_bytes(blobs_bytes)?;
+                if let Some(max_blobs_per_block) = blobs
+                    .first()
+                    .map(|blob| self.spec.max_blobs_per_block(blob.epoch()))
+                {
+                    let blobs = BlobSidecarList::from_vec(blobs, max_blobs_per_block as usize);
+                    self.block_cache
+                        .lock()
+                        .put_blobs(*block_root, blobs.clone());
+
+                    Ok(BlobSidecarListFromRoot::Blobs(blobs))
+                } else {
+                    // This always implies that there were no blobs for this block_root
+                    Ok(BlobSidecarListFromRoot::NoBlobs)
+                }
             }
-            None => Ok(None),
+            None => Ok(BlobSidecarListFromRoot::NoRoot),
         }
     }
 
     /// Fetch all keys in the data_column column with prefix `block_root`
     pub fn get_data_column_keys(&self, block_root: Hash256) -> Result<Vec<ColumnIndex>, Error> {
         self.blobs_db
-            .iter_raw_keys(DBColumn::BeaconDataColumn, block_root.as_slice())
-            .map(|key| key.and_then(|key| parse_data_column_key(key).map(|key| key.1)))
+            .iter_column_from::<Vec<u8>>(DBColumn::BeaconDataColumn, block_root.as_slice())
+            .take_while(|res| {
+                res.as_ref()
+                    .is_ok_and(|(key, _)| key.starts_with(block_root.as_slice()))
+            })
+            .map(|key| key.and_then(|(key, _)| parse_data_column_key(key).map(|key| key.1)))
             .collect()
     }
 
@@ -2092,7 +2159,7 @@ impl<E: EthSpec, Hot: ItemStore<E>, Cold: ItemStore<E>> HotColdDB<E, Hot, Cold>
         }
 
         match self.blobs_db.get_bytes(
-            DBColumn::BeaconDataColumn.into(),
+            DBColumn::BeaconDataColumn,
             &get_data_column_key(block_root, column_index),
         )? {
             Some(ref data_column_bytes) => {
@@ -2150,10 +2217,12 @@ impl<E: EthSpec, Hot: ItemStore<E>, Cold: ItemStore<E>> HotColdDB<E, Hot, Cold>
         schema_version: SchemaVersion,
         mut ops: Vec<KeyValueStoreOp>,
     ) -> Result<(), Error> {
-        let column = SchemaVersion::db_column().into();
         let key = SCHEMA_VERSION_KEY.as_slice();
-        let db_key = get_key_for_col(column, key);
-        let op = KeyValueStoreOp::PutKeyValue(db_key, schema_version.as_store_bytes());
+        let op = KeyValueStoreOp::PutKeyValue(
+            SchemaVersion::db_column(),
+            key.to_vec(),
+            schema_version.as_store_bytes(),
+        );
         ops.push(op);
 
         self.hot_db.do_atomically(ops)
@@ -2264,7 +2333,7 @@ impl<E: EthSpec, Hot: ItemStore<E>, Cold: ItemStore<E>> HotColdDB<E, Hot, Cold>
 
     /// Initialize the `DataColumnInfo` when starting from genesis or a checkpoint.
     pub fn init_data_column_info(&self, anchor_slot: Slot) -> Result<KeyValueStoreOp, Error> {
-        let oldest_data_column_slot = self.spec.eip7594_fork_epoch.map(|fork_epoch| {
+        let oldest_data_column_slot = self.spec.fulu_fork_epoch.map(|fork_epoch| {
             std::cmp::max(anchor_slot, fork_epoch.start_slot(E::slots_per_epoch()))
         });
         let data_column_info = DataColumnInfo {
@@ -2575,7 +2644,8 @@ impl<E: EthSpec, Hot: ItemStore<E>, Cold: ItemStore<E>> HotColdDB<E, Hot, Cold>
         let mut ops = vec![];
         for slot in start_slot.as_u64()..end_slot.as_u64() {
             ops.push(KeyValueStoreOp::PutKeyValue(
-                get_key_for_col(DBColumn::BeaconBlockRoots.into(), &slot.to_be_bytes()),
+                DBColumn::BeaconBlockRoots,
+                slot.to_be_bytes().to_vec(),
                 block_root.as_slice().to_vec(),
             ));
         }
@@ -2629,7 +2699,7 @@ impl<E: EthSpec, Hot: ItemStore<E>, Cold: ItemStore<E>> HotColdDB<E, Hot, Cold>
             "Pruning finalized payloads";
             "info" => "you may notice degraded I/O performance while this runs"
         );
-        let anchor_slot = self.get_anchor_info().anchor_slot;
+        let anchor_info = self.get_anchor_info();
 
         let mut ops = vec![];
         let mut last_pruned_block_root = None;
@@ -2670,10 +2740,10 @@ impl<E: EthSpec, Hot: ItemStore<E>, Cold: ItemStore<E>> HotColdDB<E, Hot, Cold>
                 ops.push(StoreOp::DeleteExecutionPayload(block_root));
             }
 
-            if slot == anchor_slot {
+            if slot <= anchor_info.oldest_block_slot {
                 info!(
                     self.log,
-                    "Payload pruning reached anchor state";
+                    "Payload pruning reached anchor oldest block slot";
                     "slot" => slot
                 );
                 break;
@@ -2797,77 +2867,62 @@ impl<E: EthSpec, Hot: ItemStore<E>, Cold: ItemStore<E>> HotColdDB<E, Hot, Cold>
             "data_availability_boundary" => data_availability_boundary,
         );
 
-        let mut ops = vec![];
-        let mut last_pruned_block_root = None;
+        // We collect block roots of deleted blobs in memory. Even for 10y of blob history this
+        // vec won't go beyond 1GB. We can probably optimise this out eventually.
+        let mut removed_block_roots = vec![];
 
-        for res in self.forwards_block_roots_iterator_until(oldest_blob_slot, end_slot, || {
-            let (_, split_state) = self
-                .get_advanced_hot_state(split.block_root, split.slot, split.state_root)?
-                .ok_or(HotColdDBError::MissingSplitState(
-                    split.state_root,
-                    split.slot,
-                ))?;
-
-            Ok((split_state, split.block_root))
-        })? {
-            let (block_root, slot) = match res {
-                Ok(tuple) => tuple,
-                Err(e) => {
-                    warn!(
-                        self.log,
-                        "Stopping blob pruning early";
-                        "error" => ?e,
-                    );
-                    break;
-                }
+        let remove_blob_if = |blobs_bytes: &[u8]| {
+            let blobs = Vec::from_ssz_bytes(blobs_bytes)?;
+            let Some(blob): Option<&Arc<BlobSidecar<E>>> = blobs.first() else {
+                return Ok(false);
             };
 
-            if Some(block_root) != last_pruned_block_root {
-                if self
-                    .spec
-                    .is_peer_das_enabled_for_epoch(slot.epoch(E::slots_per_epoch()))
-                {
-                    // data columns
-                    let indices = self.get_data_column_keys(block_root)?;
-                    if !indices.is_empty() {
-                        trace!(
-                            self.log,
-                            "Pruning data columns of block";
-                            "slot" => slot,
-                            "block_root" => ?block_root,
-                        );
-                        last_pruned_block_root = Some(block_root);
-                        ops.push(StoreOp::DeleteDataColumns(block_root, indices));
-                    }
-                } else if self.blobs_exist(&block_root)? {
-                    trace!(
-                        self.log,
-                        "Pruning blobs of block";
-                        "slot" => slot,
-                        "block_root" => ?block_root,
-                    );
-                    last_pruned_block_root = Some(block_root);
-                    ops.push(StoreOp::DeleteBlobs(block_root));
-                }
-            }
+            if blob.slot() <= end_slot {
+                // Store the block root so we can delete from the blob cache
+                removed_block_roots.push(blob.block_root());
+                // Delete from the on-disk db
+                return Ok(true);
+            };
+            Ok(false)
+        };
 
-            if slot >= end_slot {
-                break;
-            }
+        self.blobs_db
+            .delete_if(DBColumn::BeaconBlob, remove_blob_if)?;
+
+        if self.spec.is_peer_das_enabled_for_epoch(start_epoch) {
+            let remove_data_column_if = |blobs_bytes: &[u8]| {
+                let data_column: DataColumnSidecar<E> =
+                    DataColumnSidecar::from_ssz_bytes(blobs_bytes)?;
+
+                if data_column.slot() <= end_slot {
+                    return Ok(true);
+                };
+
+                Ok(false)
+            };
+
+            self.blobs_db
+                .delete_if(DBColumn::BeaconDataColumn, remove_data_column_if)?;
         }
-        let blob_lists_pruned = ops.len();
+
+        // Remove deleted blobs from the cache.
+        let mut block_cache = self.block_cache.lock();
+        for block_root in removed_block_roots {
+            block_cache.delete_blobs(&block_root);
+        }
+        drop(block_cache);
+
         let new_blob_info = BlobInfo {
             oldest_blob_slot: Some(end_slot + 1),
             blobs_db: blob_info.blobs_db,
         };
-        let update_blob_info = self.compare_and_set_blob_info(blob_info, new_blob_info)?;
-        ops.push(StoreOp::KeyValueOp(update_blob_info));
 
-        self.do_atomically_with_block_and_blobs_cache(ops)?;
+        let op = self.compare_and_set_blob_info(blob_info, new_blob_info)?;
+        self.do_atomically_with_block_and_blobs_cache(vec![StoreOp::KeyValueOp(op)])?;
+
         debug!(
             self.log,
             "Blob pruning complete";
-            "blob_lists_pruned" => blob_lists_pruned,
         );
 
         Ok(())
@@ -2930,10 +2985,7 @@ impl<E: EthSpec, Hot: ItemStore<E>, Cold: ItemStore<E>> HotColdDB<E, Hot, Cold>
         for column in columns {
             for res in self.cold_db.iter_column_keys::<Vec<u8>>(column) {
                 let key = res?;
-                cold_ops.push(KeyValueStoreOp::DeleteKey(get_key_for_col(
-                    column.as_str(),
-                    &key,
-                )));
+                cold_ops.push(KeyValueStoreOp::DeleteKey(column, key));
             }
         }
         let delete_ops = cold_ops.len();
@@ -3071,10 +3123,8 @@ pub fn migrate_database<E: EthSpec, Hot: ItemStore<E>, Cold: ItemStore<E>>(
 
         // Store the slot to block root mapping.
         cold_db_block_ops.push(KeyValueStoreOp::PutKeyValue(
-            get_key_for_col(
-                DBColumn::BeaconBlockRoots.into(),
-                &slot.as_u64().to_be_bytes(),
-            ),
+            DBColumn::BeaconBlockRoots,
+            slot.as_u64().to_be_bytes().to_vec(),
             block_root.as_slice().to_vec(),
         ));
 
@@ -3325,3 +3375,57 @@ impl StoreItem for TemporaryFlag {
         Ok(TemporaryFlag)
     }
 }
+
+#[derive(Debug, Clone, PartialEq, Eq, PartialOrd, Ord)]
+pub struct BytesKey {
+    pub key: Vec<u8>,
+}
+
+impl db_key::Key for BytesKey {
+    fn from_u8(key: &[u8]) -> Self {
+        Self { key: key.to_vec() }
+    }
+
+    fn as_slice<T, F: Fn(&[u8]) -> T>(&self, f: F) -> T {
+        f(self.key.as_slice())
+    }
+}
+
+impl BytesKey {
+    pub fn starts_with(&self, prefix: &Self) -> bool {
+        self.key.starts_with(&prefix.key)
+    }
+
+    /// Return `true` iff this `BytesKey` was created with the given `column`.
+    pub fn matches_column(&self, column: DBColumn) -> bool {
+        self.key.starts_with(column.as_bytes())
+    }
+
+    /// Remove the column from a key, returning its `Hash256` portion.
+    pub fn remove_column(&self, column: DBColumn) -> Option<Hash256> {
+        if self.matches_column(column) {
+            let subkey = &self.key[column.as_bytes().len()..];
+            if subkey.len() == 32 {
+                return Some(Hash256::from_slice(subkey));
+            }
+        }
+        None
+    }
+
+    /// Remove the column from a key.
+    ///
+    /// Will return `None` if the value doesn't match the column or has the wrong length.
+    pub fn remove_column_variable(&self, column: DBColumn) -> Option<&[u8]> {
+        if self.matches_column(column) {
+            let subkey = &self.key[column.as_bytes().len()..];
+            if subkey.len() == column.key_size() {
+                return Some(subkey);
+            }
+        }
+        None
+    }
+
+    pub fn from_vec(key: Vec<u8>) -> Self {
+        Self { key }
+    }
+}
diff --git a/beacon_node/store/src/impls/beacon_state.rs b/beacon_node/store/src/impls/beacon_state.rs
index 48c289f2b2..fd08e547f1 100644
--- a/beacon_node/store/src/impls/beacon_state.rs
+++ b/beacon_node/store/src/impls/beacon_state.rs
@@ -13,8 +13,11 @@ pub fn store_full_state<E: EthSpec>(
     };
     metrics::inc_counter_by(&metrics::BEACON_STATE_WRITE_BYTES, bytes.len() as u64);
     metrics::inc_counter(&metrics::BEACON_STATE_WRITE_COUNT);
-    let key = get_key_for_col(DBColumn::BeaconState.into(), state_root.as_slice());
-    ops.push(KeyValueStoreOp::PutKeyValue(key, bytes));
+    ops.push(KeyValueStoreOp::PutKeyValue(
+        DBColumn::BeaconState,
+        state_root.as_slice().to_vec(),
+        bytes,
+    ));
     Ok(())
 }
 
@@ -25,7 +28,7 @@ pub fn get_full_state<KV: KeyValueStore<E>, E: EthSpec>(
 ) -> Result<Option<BeaconState<E>>, Error> {
     let total_timer = metrics::start_timer(&metrics::BEACON_STATE_READ_TIMES);
 
-    match db.get_bytes(DBColumn::BeaconState.into(), state_root.as_slice())? {
+    match db.get_bytes(DBColumn::BeaconState, state_root.as_slice())? {
         Some(bytes) => {
             let overhead_timer = metrics::start_timer(&metrics::BEACON_STATE_READ_OVERHEAD_TIMES);
             let container = StorageContainer::from_ssz_bytes(&bytes, spec)?;
diff --git a/beacon_node/store/src/impls/execution_payload.rs b/beacon_node/store/src/impls/execution_payload.rs
index 14fc10ad6d..097b069a66 100644
--- a/beacon_node/store/src/impls/execution_payload.rs
+++ b/beacon_node/store/src/impls/execution_payload.rs
@@ -1,8 +1,8 @@
 use crate::{DBColumn, Error, StoreItem};
 use ssz::{Decode, Encode};
 use types::{
-    BlobSidecarList, EthSpec, ExecutionPayload, ExecutionPayloadBellatrix, ExecutionPayloadCapella,
-    ExecutionPayloadDeneb, ExecutionPayloadElectra,
+    EthSpec, ExecutionPayload, ExecutionPayloadBellatrix, ExecutionPayloadCapella,
+    ExecutionPayloadDeneb, ExecutionPayloadElectra, ExecutionPayloadFulu,
 };
 
 macro_rules! impl_store_item {
@@ -26,7 +26,7 @@ impl_store_item!(ExecutionPayloadBellatrix);
 impl_store_item!(ExecutionPayloadCapella);
 impl_store_item!(ExecutionPayloadDeneb);
 impl_store_item!(ExecutionPayloadElectra);
-impl_store_item!(BlobSidecarList);
+impl_store_item!(ExecutionPayloadFulu);
 
 /// This fork-agnostic implementation should be only used for writing.
 ///
@@ -42,17 +42,21 @@ impl<E: EthSpec> StoreItem for ExecutionPayload<E> {
     }
 
     fn from_store_bytes(bytes: &[u8]) -> Result<Self, Error> {
-        ExecutionPayloadElectra::from_ssz_bytes(bytes)
-            .map(Self::Electra)
+        ExecutionPayloadFulu::from_ssz_bytes(bytes)
+            .map(Self::Fulu)
             .or_else(|_| {
-                ExecutionPayloadDeneb::from_ssz_bytes(bytes)
-                    .map(Self::Deneb)
+                ExecutionPayloadElectra::from_ssz_bytes(bytes)
+                    .map(Self::Electra)
                     .or_else(|_| {
-                        ExecutionPayloadCapella::from_ssz_bytes(bytes)
-                            .map(Self::Capella)
+                        ExecutionPayloadDeneb::from_ssz_bytes(bytes)
+                            .map(Self::Deneb)
                             .or_else(|_| {
-                                ExecutionPayloadBellatrix::from_ssz_bytes(bytes)
-                                    .map(Self::Bellatrix)
+                                ExecutionPayloadCapella::from_ssz_bytes(bytes)
+                                    .map(Self::Capella)
+                                    .or_else(|_| {
+                                        ExecutionPayloadBellatrix::from_ssz_bytes(bytes)
+                                            .map(Self::Bellatrix)
+                                    })
                             })
                     })
             })
diff --git a/beacon_node/store/src/leveldb_store.rs b/beacon_node/store/src/leveldb_store.rs
deleted file mode 100644
index 720afd0f3f..0000000000
--- a/beacon_node/store/src/leveldb_store.rs
+++ /dev/null
@@ -1,310 +0,0 @@
-use super::*;
-use crate::hot_cold_store::HotColdDBError;
-use leveldb::compaction::Compaction;
-use leveldb::database::batch::{Batch, Writebatch};
-use leveldb::database::kv::KV;
-use leveldb::database::Database;
-use leveldb::error::Error as LevelDBError;
-use leveldb::iterator::{Iterable, KeyIterator, LevelDBIterator};
-use leveldb::options::{Options, ReadOptions, WriteOptions};
-use parking_lot::Mutex;
-use std::marker::PhantomData;
-use std::path::Path;
-
-/// A wrapped leveldb database.
-pub struct LevelDB<E: EthSpec> {
-    db: Database<BytesKey>,
-    /// A mutex to synchronise sensitive read-write transactions.
-    transaction_mutex: Mutex<()>,
-    _phantom: PhantomData<E>,
-}
-
-impl<E: EthSpec> LevelDB<E> {
-    /// Open a database at `path`, creating a new database if one does not already exist.
-    pub fn open(path: &Path) -> Result<Self, Error> {
-        let mut options = Options::new();
-
-        options.create_if_missing = true;
-
-        let db = Database::open(path, options)?;
-        let transaction_mutex = Mutex::new(());
-
-        Ok(Self {
-            db,
-            transaction_mutex,
-            _phantom: PhantomData,
-        })
-    }
-
-    fn read_options(&self) -> ReadOptions<BytesKey> {
-        ReadOptions::new()
-    }
-
-    fn write_options(&self) -> WriteOptions {
-        WriteOptions::new()
-    }
-
-    fn write_options_sync(&self) -> WriteOptions {
-        let mut opts = WriteOptions::new();
-        opts.sync = true;
-        opts
-    }
-
-    fn put_bytes_with_options(
-        &self,
-        col: &str,
-        key: &[u8],
-        val: &[u8],
-        opts: WriteOptions,
-    ) -> Result<(), Error> {
-        let column_key = get_key_for_col(col, key);
-
-        metrics::inc_counter_vec(&metrics::DISK_DB_WRITE_COUNT, &[col]);
-        metrics::inc_counter_vec_by(&metrics::DISK_DB_WRITE_BYTES, &[col], val.len() as u64);
-        let _timer = metrics::start_timer(&metrics::DISK_DB_WRITE_TIMES);
-
-        self.db
-            .put(opts, BytesKey::from_vec(column_key), val)
-            .map_err(Into::into)
-    }
-
-    pub fn keys_iter(&self) -> KeyIterator<BytesKey> {
-        self.db.keys_iter(self.read_options())
-    }
-}
-
-impl<E: EthSpec> KeyValueStore<E> for LevelDB<E> {
-    /// Store some `value` in `column`, indexed with `key`.
-    fn put_bytes(&self, col: &str, key: &[u8], val: &[u8]) -> Result<(), Error> {
-        self.put_bytes_with_options(col, key, val, self.write_options())
-    }
-
-    fn put_bytes_sync(&self, col: &str, key: &[u8], val: &[u8]) -> Result<(), Error> {
-        self.put_bytes_with_options(col, key, val, self.write_options_sync())
-    }
-
-    fn sync(&self) -> Result<(), Error> {
-        self.put_bytes_sync("sync", b"sync", b"sync")
-    }
-
-    /// Retrieve some bytes in `column` with `key`.
-    fn get_bytes(&self, col: &str, key: &[u8]) -> Result<Option<Vec<u8>>, Error> {
-        let column_key = get_key_for_col(col, key);
-
-        metrics::inc_counter_vec(&metrics::DISK_DB_READ_COUNT, &[col]);
-        let timer = metrics::start_timer(&metrics::DISK_DB_READ_TIMES);
-
-        self.db
-            .get(self.read_options(), BytesKey::from_vec(column_key))
-            .map_err(Into::into)
-            .map(|opt| {
-                opt.inspect(|bytes| {
-                    metrics::inc_counter_vec_by(
-                        &metrics::DISK_DB_READ_BYTES,
-                        &[col],
-                        bytes.len() as u64,
-                    );
-                    metrics::stop_timer(timer);
-                })
-            })
-    }
-
-    /// Return `true` if `key` exists in `column`.
-    fn key_exists(&self, col: &str, key: &[u8]) -> Result<bool, Error> {
-        let column_key = get_key_for_col(col, key);
-
-        metrics::inc_counter_vec(&metrics::DISK_DB_EXISTS_COUNT, &[col]);
-
-        self.db
-            .get(self.read_options(), BytesKey::from_vec(column_key))
-            .map_err(Into::into)
-            .map(|val| val.is_some())
-    }
-
-    /// Removes `key` from `column`.
-    fn key_delete(&self, col: &str, key: &[u8]) -> Result<(), Error> {
-        let column_key = get_key_for_col(col, key);
-
-        metrics::inc_counter_vec(&metrics::DISK_DB_DELETE_COUNT, &[col]);
-
-        self.db
-            .delete(self.write_options(), BytesKey::from_vec(column_key))
-            .map_err(Into::into)
-    }
-
-    fn do_atomically(&self, ops_batch: Vec<KeyValueStoreOp>) -> Result<(), Error> {
-        let mut leveldb_batch = Writebatch::new();
-        for op in ops_batch {
-            match op {
-                KeyValueStoreOp::PutKeyValue(key, value) => {
-                    let col = get_col_from_key(&key).unwrap_or("unknown".to_owned());
-                    metrics::inc_counter_vec(&metrics::DISK_DB_WRITE_COUNT, &[&col]);
-                    metrics::inc_counter_vec_by(
-                        &metrics::DISK_DB_WRITE_BYTES,
-                        &[&col],
-                        value.len() as u64,
-                    );
-
-                    leveldb_batch.put(BytesKey::from_vec(key), &value);
-                }
-
-                KeyValueStoreOp::DeleteKey(key) => {
-                    let col = get_col_from_key(&key).unwrap_or("unknown".to_owned());
-                    metrics::inc_counter_vec(&metrics::DISK_DB_DELETE_COUNT, &[&col]);
-
-                    leveldb_batch.delete(BytesKey::from_vec(key));
-                }
-            }
-        }
-
-        let _timer = metrics::start_timer(&metrics::DISK_DB_WRITE_TIMES);
-
-        self.db.write(self.write_options(), &leveldb_batch)?;
-        Ok(())
-    }
-
-    fn begin_rw_transaction(&self) -> MutexGuard<()> {
-        self.transaction_mutex.lock()
-    }
-
-    fn compact_column(&self, column: DBColumn) -> Result<(), Error> {
-        // Use key-size-agnostic keys [] and 0xff..ff with a minimum of 32 bytes to account for
-        // columns that may change size between sub-databases or schema versions.
-        let start_key = BytesKey::from_vec(get_key_for_col(column.as_str(), &[]));
-        let end_key = BytesKey::from_vec(get_key_for_col(
-            column.as_str(),
-            &vec![0xff; std::cmp::max(column.key_size(), 32)],
-        ));
-        self.db.compact(&start_key, &end_key);
-        Ok(())
-    }
-
-    fn iter_column_from<K: Key>(&self, column: DBColumn, from: &[u8]) -> ColumnIter<K> {
-        let start_key = BytesKey::from_vec(get_key_for_col(column.into(), from));
-        let iter = self.db.iter(self.read_options());
-        iter.seek(&start_key);
-
-        Box::new(
-            iter.take_while(move |(key, _)| key.matches_column(column))
-                .map(move |(bytes_key, value)| {
-                    let key = bytes_key.remove_column_variable(column).ok_or_else(|| {
-                        HotColdDBError::IterationError {
-                            unexpected_key: bytes_key.clone(),
-                        }
-                    })?;
-                    Ok((K::from_bytes(key)?, value))
-                }),
-        )
-    }
-
-    fn iter_raw_entries(&self, column: DBColumn, prefix: &[u8]) -> RawEntryIter {
-        let start_key = BytesKey::from_vec(get_key_for_col(column.into(), prefix));
-
-        let iter = self.db.iter(self.read_options());
-        iter.seek(&start_key);
-
-        Box::new(
-            iter.take_while(move |(key, _)| key.key.starts_with(start_key.key.as_slice()))
-                .map(move |(bytes_key, value)| {
-                    let subkey = &bytes_key.key[column.as_bytes().len()..];
-                    Ok((Vec::from(subkey), value))
-                }),
-        )
-    }
-
-    fn iter_raw_keys(&self, column: DBColumn, prefix: &[u8]) -> RawKeyIter {
-        let start_key = BytesKey::from_vec(get_key_for_col(column.into(), prefix));
-
-        let iter = self.db.keys_iter(self.read_options());
-        iter.seek(&start_key);
-
-        Box::new(
-            iter.take_while(move |key| key.key.starts_with(start_key.key.as_slice()))
-                .map(move |bytes_key| {
-                    let subkey = &bytes_key.key[column.as_bytes().len()..];
-                    Ok(Vec::from(subkey))
-                }),
-        )
-    }
-
-    /// Iterate through all keys and values in a particular column.
-    fn iter_column_keys<K: Key>(&self, column: DBColumn) -> ColumnKeyIter<K> {
-        let start_key =
-            BytesKey::from_vec(get_key_for_col(column.into(), &vec![0; column.key_size()]));
-
-        let iter = self.db.keys_iter(self.read_options());
-        iter.seek(&start_key);
-
-        Box::new(
-            iter.take_while(move |key| key.matches_column(column))
-                .map(move |bytes_key| {
-                    let key = bytes_key.remove_column_variable(column).ok_or_else(|| {
-                        HotColdDBError::IterationError {
-                            unexpected_key: bytes_key.clone(),
-                        }
-                    })?;
-                    K::from_bytes(key)
-                }),
-        )
-    }
-}
-
-impl<E: EthSpec> ItemStore<E> for LevelDB<E> {}
-
-/// Used for keying leveldb.
-#[derive(Debug, Clone, PartialEq, Eq, PartialOrd, Ord)]
-pub struct BytesKey {
-    key: Vec<u8>,
-}
-
-impl db_key::Key for BytesKey {
-    fn from_u8(key: &[u8]) -> Self {
-        Self { key: key.to_vec() }
-    }
-
-    fn as_slice<T, F: Fn(&[u8]) -> T>(&self, f: F) -> T {
-        f(self.key.as_slice())
-    }
-}
-
-impl BytesKey {
-    pub fn starts_with(&self, prefix: &Self) -> bool {
-        self.key.starts_with(&prefix.key)
-    }
-
-    /// Return `true` iff this `BytesKey` was created with the given `column`.
-    pub fn matches_column(&self, column: DBColumn) -> bool {
-        self.key.starts_with(column.as_bytes())
-    }
-
-    /// Remove the column from a 32 byte key, yielding the `Hash256` key.
-    pub fn remove_column(&self, column: DBColumn) -> Option<Hash256> {
-        let key = self.remove_column_variable(column)?;
-        (column.key_size() == 32).then(|| Hash256::from_slice(key))
-    }
-
-    /// Remove the column from a key.
-    ///
-    /// Will return `None` if the value doesn't match the column or has the wrong length.
-    pub fn remove_column_variable(&self, column: DBColumn) -> Option<&[u8]> {
-        if self.matches_column(column) {
-            let subkey = &self.key[column.as_bytes().len()..];
-            if subkey.len() == column.key_size() {
-                return Some(subkey);
-            }
-        }
-        None
-    }
-
-    pub fn from_vec(key: Vec<u8>) -> Self {
-        Self { key }
-    }
-}
-
-impl From<LevelDBError> for Error {
-    fn from(e: LevelDBError) -> Error {
-        Error::DBError {
-            message: format!("{:?}", e),
-        }
-    }
-}
diff --git a/beacon_node/store/src/lib.rs b/beacon_node/store/src/lib.rs
index 09ae9a32dd..0cfc42ab15 100644
--- a/beacon_node/store/src/lib.rs
+++ b/beacon_node/store/src/lib.rs
@@ -7,6 +7,7 @@
 //!
 //! Provides a simple API for storing/retrieving all types that sometimes needs type-hints. See
 //! tests for implementation examples.
+pub mod blob_sidecar_list_from_root;
 pub mod chunked_iter;
 pub mod chunked_vector;
 pub mod config;
@@ -18,7 +19,6 @@ pub mod hdiff;
 pub mod historic_state_cache;
 pub mod hot_cold_store;
 mod impls;
-mod leveldb_store;
 mod memory_store;
 pub mod metadata;
 pub mod metrics;
@@ -26,12 +26,13 @@ pub mod partial_beacon_state;
 pub mod reconstruct;
 pub mod state_cache;
 
+pub mod database;
 pub mod iter;
 
+pub use self::blob_sidecar_list_from_root::BlobSidecarListFromRoot;
 pub use self::config::StoreConfig;
 pub use self::consensus_context::OnDiskConsensusContext;
 pub use self::hot_cold_store::{HotColdDB, HotStateSummary, Split};
-pub use self::leveldb_store::LevelDB;
 pub use self::memory_store::MemoryStore;
 pub use crate::metadata::BlobInfo;
 pub use errors::Error;
@@ -39,8 +40,9 @@ pub use impls::beacon_state::StorageContainer as BeaconStateStorageContainer;
 pub use metadata::AnchorInfo;
 pub use metrics::scrape_for_metrics;
 use parking_lot::MutexGuard;
+use std::collections::HashSet;
 use std::sync::Arc;
-use strum::{EnumString, IntoStaticStr};
+use strum::{EnumIter, EnumString, IntoStaticStr};
 pub use types::*;
 
 const DATA_COLUMN_DB_KEY_SIZE: usize = 32 + 8;
@@ -48,18 +50,18 @@ const DATA_COLUMN_DB_KEY_SIZE: usize = 32 + 8;
 pub type ColumnIter<'a, K> = Box<dyn Iterator<Item = Result<(K, Vec<u8>), Error>> + 'a>;
 pub type ColumnKeyIter<'a, K> = Box<dyn Iterator<Item = Result<K, Error>> + 'a>;
 
-pub type RawEntryIter<'a> = Box<dyn Iterator<Item = Result<(Vec<u8>, Vec<u8>), Error>> + 'a>;
-pub type RawKeyIter<'a> = Box<dyn Iterator<Item = Result<Vec<u8>, Error>> + 'a>;
+pub type RawEntryIter<'a> =
+    Result<Box<dyn Iterator<Item = Result<(Vec<u8>, Vec<u8>), Error>> + 'a>, Error>;
 
 pub trait KeyValueStore<E: EthSpec>: Sync + Send + Sized + 'static {
     /// Retrieve some bytes in `column` with `key`.
-    fn get_bytes(&self, column: &str, key: &[u8]) -> Result<Option<Vec<u8>>, Error>;
+    fn get_bytes(&self, column: DBColumn, key: &[u8]) -> Result<Option<Vec<u8>>, Error>;
 
     /// Store some `value` in `column`, indexed with `key`.
-    fn put_bytes(&self, column: &str, key: &[u8], value: &[u8]) -> Result<(), Error>;
+    fn put_bytes(&self, column: DBColumn, key: &[u8], value: &[u8]) -> Result<(), Error>;
 
     /// Same as put_bytes() but also force a flush to disk
-    fn put_bytes_sync(&self, column: &str, key: &[u8], value: &[u8]) -> Result<(), Error>;
+    fn put_bytes_sync(&self, column: DBColumn, key: &[u8], value: &[u8]) -> Result<(), Error>;
 
     /// Flush to disk.  See
     /// https://chromium.googlesource.com/external/leveldb/+/HEAD/doc/index.md#synchronous-writes
@@ -67,10 +69,10 @@ pub trait KeyValueStore<E: EthSpec>: Sync + Send + Sized + 'static {
     fn sync(&self) -> Result<(), Error>;
 
     /// Return `true` if `key` exists in `column`.
-    fn key_exists(&self, column: &str, key: &[u8]) -> Result<bool, Error>;
+    fn key_exists(&self, column: DBColumn, key: &[u8]) -> Result<bool, Error>;
 
     /// Removes `key` from `column`.
-    fn key_delete(&self, column: &str, key: &[u8]) -> Result<(), Error>;
+    fn key_delete(&self, column: DBColumn, key: &[u8]) -> Result<(), Error>;
 
     /// Execute either all of the operations in `batch` or none at all, returning an error.
     fn do_atomically(&self, batch: Vec<KeyValueStoreOp>) -> Result<(), Error>;
@@ -103,17 +105,21 @@ pub trait KeyValueStore<E: EthSpec>: Sync + Send + Sized + 'static {
         self.iter_column_from(column, &vec![0; column.key_size()])
     }
 
-    /// Iterate through all keys and values in a column from a given starting point.
+    /// Iterate through all keys and values in a column from a given starting point that fulfill the given predicate.
     fn iter_column_from<K: Key>(&self, column: DBColumn, from: &[u8]) -> ColumnIter<K>;
 
-    fn iter_raw_entries(&self, _column: DBColumn, _prefix: &[u8]) -> RawEntryIter {
-        Box::new(std::iter::empty())
-    }
-
-    fn iter_raw_keys(&self, column: DBColumn, prefix: &[u8]) -> RawKeyIter;
+    fn iter_column_keys<K: Key>(&self, column: DBColumn) -> ColumnKeyIter<K>;
 
     /// Iterate through all keys in a particular column.
-    fn iter_column_keys<K: Key>(&self, column: DBColumn) -> ColumnKeyIter<K>;
+    fn iter_column_keys_from<K: Key>(&self, column: DBColumn, from: &[u8]) -> ColumnKeyIter<K>;
+
+    fn delete_batch(&self, column: DBColumn, ops: HashSet<&[u8]>) -> Result<(), Error>;
+
+    fn delete_if(
+        &self,
+        column: DBColumn,
+        f: impl FnMut(&[u8]) -> Result<bool, Error>,
+    ) -> Result<(), Error>;
 }
 
 pub trait Key: Sized + 'static {
@@ -136,7 +142,7 @@ impl Key for Vec<u8> {
     }
 }
 
-pub fn get_key_for_col(column: &str, key: &[u8]) -> Vec<u8> {
+pub fn get_key_for_col(column: DBColumn, key: &[u8]) -> Vec<u8> {
     let mut result = column.as_bytes().to_vec();
     result.extend_from_slice(key);
     result
@@ -174,14 +180,18 @@ pub fn parse_data_column_key(data: Vec<u8>) -> Result<(Hash256, ColumnIndex), Er
 #[must_use]
 #[derive(Clone)]
 pub enum KeyValueStoreOp {
-    PutKeyValue(Vec<u8>, Vec<u8>),
-    DeleteKey(Vec<u8>),
+    // Indicate that a PUT operation should be made
+    // to the db store for a (Column, Key, Value)
+    PutKeyValue(DBColumn, Vec<u8>, Vec<u8>),
+    // Indicate that a DELETE operation should be made
+    // to the db store for a (Column, Key)
+    DeleteKey(DBColumn, Vec<u8>),
 }
 
 pub trait ItemStore<E: EthSpec>: KeyValueStore<E> + Sync + Send + Sized + 'static {
     /// Store an item in `Self`.
     fn put<I: StoreItem>(&self, key: &Hash256, item: &I) -> Result<(), Error> {
-        let column = I::db_column().into();
+        let column = I::db_column();
         let key = key.as_slice();
 
         self.put_bytes(column, key, &item.as_store_bytes())
@@ -189,7 +199,7 @@ pub trait ItemStore<E: EthSpec>: KeyValueStore<E> + Sync + Send + Sized + 'stati
     }
 
     fn put_sync<I: StoreItem>(&self, key: &Hash256, item: &I) -> Result<(), Error> {
-        let column = I::db_column().into();
+        let column = I::db_column();
         let key = key.as_slice();
 
         self.put_bytes_sync(column, key, &item.as_store_bytes())
@@ -198,7 +208,7 @@ pub trait ItemStore<E: EthSpec>: KeyValueStore<E> + Sync + Send + Sized + 'stati
 
     /// Retrieve an item from `Self`.
     fn get<I: StoreItem>(&self, key: &Hash256) -> Result<Option<I>, Error> {
-        let column = I::db_column().into();
+        let column = I::db_column();
         let key = key.as_slice();
 
         match self.get_bytes(column, key)? {
@@ -209,7 +219,7 @@ pub trait ItemStore<E: EthSpec>: KeyValueStore<E> + Sync + Send + Sized + 'stati
 
     /// Returns `true` if the given key represents an item in `Self`.
     fn exists<I: StoreItem>(&self, key: &Hash256) -> Result<bool, Error> {
-        let column = I::db_column().into();
+        let column = I::db_column();
         let key = key.as_slice();
 
         self.key_exists(column, key)
@@ -217,7 +227,7 @@ pub trait ItemStore<E: EthSpec>: KeyValueStore<E> + Sync + Send + Sized + 'stati
 
     /// Remove an item from `Self`.
     fn delete<I: StoreItem>(&self, key: &Hash256) -> Result<(), Error> {
-        let column = I::db_column().into();
+        let column = I::db_column();
         let key = key.as_slice();
 
         self.key_delete(column, key)
@@ -245,7 +255,7 @@ pub enum StoreOp<'a, E: EthSpec> {
 }
 
 /// A unique column identifier.
-#[derive(Debug, Clone, Copy, PartialEq, IntoStaticStr, EnumString)]
+#[derive(Debug, Clone, Copy, PartialEq, IntoStaticStr, EnumString, EnumIter)]
 pub enum DBColumn {
     /// For data related to the database itself.
     #[strum(serialize = "bma")]
@@ -349,6 +359,9 @@ pub enum DBColumn {
     /// For helping persist eagerly computed light client bootstrap data
     #[strum(serialize = "scm")]
     SyncCommittee,
+    /// The dummy table is used to force the db to sync
+    #[strum(serialize = "dmy")]
+    Dummy,
 }
 
 /// A block from the database, which might have an execution payload or not.
@@ -399,7 +412,8 @@ impl DBColumn {
             | Self::BeaconStateDiff
             | Self::SyncCommittee
             | Self::SyncCommitteeBranch
-            | Self::LightClientUpdate => 8,
+            | Self::LightClientUpdate
+            | Self::Dummy => 8,
             Self::BeaconDataColumn => DATA_COLUMN_DB_KEY_SIZE,
         }
     }
@@ -419,13 +433,18 @@ pub trait StoreItem: Sized {
     fn from_store_bytes(bytes: &[u8]) -> Result<Self, Error>;
 
     fn as_kv_store_op(&self, key: Hash256) -> KeyValueStoreOp {
-        let db_key = get_key_for_col(Self::db_column().into(), key.as_slice());
-        KeyValueStoreOp::PutKeyValue(db_key, self.as_store_bytes())
+        KeyValueStoreOp::PutKeyValue(
+            Self::db_column(),
+            key.as_slice().to_vec(),
+            self.as_store_bytes(),
+        )
     }
 }
 
 #[cfg(test)]
 mod tests {
+    use crate::database::interface::BeaconNodeBackend;
+
     use super::*;
     use ssz::{Decode, Encode};
     use ssz_derive::{Decode, Encode};
@@ -475,7 +494,7 @@ mod tests {
     fn simplediskdb() {
         let dir = tempdir().unwrap();
         let path = dir.path();
-        let store = LevelDB::open(path).unwrap();
+        let store = BeaconNodeBackend::open(&StoreConfig::default(), path).unwrap();
 
         test_impl(store);
     }
@@ -506,7 +525,7 @@ mod tests {
 
     #[test]
     fn test_get_col_from_key() {
-        let key = get_key_for_col(DBColumn::BeaconBlock.into(), &[1u8; 32]);
+        let key = get_key_for_col(DBColumn::BeaconBlock, &[1u8; 32]);
         let col = get_col_from_key(&key).unwrap();
         assert_eq!(col, "blk");
     }
diff --git a/beacon_node/store/src/memory_store.rs b/beacon_node/store/src/memory_store.rs
index 4c7bfdf10f..6070a2d3f0 100644
--- a/beacon_node/store/src/memory_store.rs
+++ b/beacon_node/store/src/memory_store.rs
@@ -1,9 +1,9 @@
 use crate::{
-    get_key_for_col, leveldb_store::BytesKey, ColumnIter, ColumnKeyIter, DBColumn, Error,
-    ItemStore, Key, KeyValueStore, KeyValueStoreOp, RawKeyIter,
+    errors::Error as DBError, get_key_for_col, hot_cold_store::BytesKey, ColumnIter, ColumnKeyIter,
+    DBColumn, Error, ItemStore, Key, KeyValueStore, KeyValueStoreOp,
 };
 use parking_lot::{Mutex, MutexGuard, RwLock};
-use std::collections::BTreeMap;
+use std::collections::{BTreeMap, HashSet};
 use std::marker::PhantomData;
 use types::*;
 
@@ -29,19 +29,19 @@ impl<E: EthSpec> MemoryStore<E> {
 
 impl<E: EthSpec> KeyValueStore<E> for MemoryStore<E> {
     /// Get the value of some key from the database. Returns `None` if the key does not exist.
-    fn get_bytes(&self, col: &str, key: &[u8]) -> Result<Option<Vec<u8>>, Error> {
+    fn get_bytes(&self, col: DBColumn, key: &[u8]) -> Result<Option<Vec<u8>>, Error> {
         let column_key = BytesKey::from_vec(get_key_for_col(col, key));
         Ok(self.db.read().get(&column_key).cloned())
     }
 
     /// Puts a key in the database.
-    fn put_bytes(&self, col: &str, key: &[u8], val: &[u8]) -> Result<(), Error> {
+    fn put_bytes(&self, col: DBColumn, key: &[u8], val: &[u8]) -> Result<(), Error> {
         let column_key = BytesKey::from_vec(get_key_for_col(col, key));
         self.db.write().insert(column_key, val.to_vec());
         Ok(())
     }
 
-    fn put_bytes_sync(&self, col: &str, key: &[u8], val: &[u8]) -> Result<(), Error> {
+    fn put_bytes_sync(&self, col: DBColumn, key: &[u8], val: &[u8]) -> Result<(), Error> {
         self.put_bytes(col, key, val)
     }
 
@@ -51,13 +51,13 @@ impl<E: EthSpec> KeyValueStore<E> for MemoryStore<E> {
     }
 
     /// Return true if some key exists in some column.
-    fn key_exists(&self, col: &str, key: &[u8]) -> Result<bool, Error> {
+    fn key_exists(&self, col: DBColumn, key: &[u8]) -> Result<bool, Error> {
         let column_key = BytesKey::from_vec(get_key_for_col(col, key));
         Ok(self.db.read().contains_key(&column_key))
     }
 
     /// Delete some key from the database.
-    fn key_delete(&self, col: &str, key: &[u8]) -> Result<(), Error> {
+    fn key_delete(&self, col: DBColumn, key: &[u8]) -> Result<(), Error> {
         let column_key = BytesKey::from_vec(get_key_for_col(col, key));
         self.db.write().remove(&column_key);
         Ok(())
@@ -66,12 +66,16 @@ impl<E: EthSpec> KeyValueStore<E> for MemoryStore<E> {
     fn do_atomically(&self, batch: Vec<KeyValueStoreOp>) -> Result<(), Error> {
         for op in batch {
             match op {
-                KeyValueStoreOp::PutKeyValue(key, value) => {
-                    self.db.write().insert(BytesKey::from_vec(key), value);
+                KeyValueStoreOp::PutKeyValue(col, key, value) => {
+                    let column_key = get_key_for_col(col, &key);
+                    self.db
+                        .write()
+                        .insert(BytesKey::from_vec(column_key), value);
                 }
 
-                KeyValueStoreOp::DeleteKey(key) => {
-                    self.db.write().remove(&BytesKey::from_vec(key));
+                KeyValueStoreOp::DeleteKey(col, key) => {
+                    let column_key = get_key_for_col(col, &key);
+                    self.db.write().remove(&BytesKey::from_vec(column_key));
                 }
             }
         }
@@ -82,8 +86,7 @@ impl<E: EthSpec> KeyValueStore<E> for MemoryStore<E> {
         // We use this awkward pattern because we can't lock the `self.db` field *and* maintain a
         // reference to the lock guard across calls to `.next()`. This would be require a
         // struct with a field (the iterator) which references another field (the lock guard).
-        let start_key = BytesKey::from_vec(get_key_for_col(column.as_str(), from));
-        let col = column.as_str();
+        let start_key = BytesKey::from_vec(get_key_for_col(column, from));
         let keys = self
             .db
             .read()
@@ -92,7 +95,7 @@ impl<E: EthSpec> KeyValueStore<E> for MemoryStore<E> {
             .filter_map(|(k, _)| k.remove_column_variable(column).map(|k| k.to_vec()))
             .collect::<Vec<_>>();
         Box::new(keys.into_iter().filter_map(move |key| {
-            self.get_bytes(col, &key).transpose().map(|res| {
+            self.get_bytes(column, &key).transpose().map(|res| {
                 let k = K::from_bytes(&key)?;
                 let v = res?;
                 Ok((k, v))
@@ -100,18 +103,6 @@ impl<E: EthSpec> KeyValueStore<E> for MemoryStore<E> {
         }))
     }
 
-    fn iter_raw_keys(&self, column: DBColumn, prefix: &[u8]) -> RawKeyIter {
-        let start_key = BytesKey::from_vec(get_key_for_col(column.as_str(), prefix));
-        let keys = self
-            .db
-            .read()
-            .range(start_key.clone()..)
-            .take_while(|(k, _)| k.starts_with(&start_key))
-            .filter_map(|(k, _)| k.remove_column_variable(column).map(|k| k.to_vec()))
-            .collect::<Vec<_>>();
-        Box::new(keys.into_iter().map(Ok))
-    }
-
     fn iter_column_keys<K: Key>(&self, column: DBColumn) -> ColumnKeyIter<K> {
         Box::new(self.iter_column(column).map(|res| res.map(|(k, _)| k)))
     }
@@ -123,6 +114,44 @@ impl<E: EthSpec> KeyValueStore<E> for MemoryStore<E> {
     fn compact_column(&self, _column: DBColumn) -> Result<(), Error> {
         Ok(())
     }
+
+    fn iter_column_keys_from<K: Key>(&self, column: DBColumn, from: &[u8]) -> ColumnKeyIter<K> {
+        // We use this awkward pattern because we can't lock the `self.db` field *and* maintain a
+        // reference to the lock guard across calls to `.next()`. This would be require a
+        // struct with a field (the iterator) which references another field (the lock guard).
+        let start_key = BytesKey::from_vec(get_key_for_col(column, from));
+        let keys = self
+            .db
+            .read()
+            .range(start_key..)
+            .take_while(|(k, _)| k.remove_column_variable(column).is_some())
+            .filter_map(|(k, _)| k.remove_column_variable(column).map(|k| k.to_vec()))
+            .collect::<Vec<_>>();
+        Box::new(keys.into_iter().map(move |key| K::from_bytes(&key)))
+    }
+
+    fn delete_batch(&self, col: DBColumn, ops: HashSet<&[u8]>) -> Result<(), DBError> {
+        for op in ops {
+            let column_key = get_key_for_col(col, op);
+            self.db.write().remove(&BytesKey::from_vec(column_key));
+        }
+        Ok(())
+    }
+
+    fn delete_if(
+        &self,
+        column: DBColumn,
+        mut f: impl FnMut(&[u8]) -> Result<bool, Error>,
+    ) -> Result<(), Error> {
+        self.db.write().retain(|key, value| {
+            if key.remove_column_variable(column).is_some() {
+                !f(value).unwrap_or(false)
+            } else {
+                true
+            }
+        });
+        Ok(())
+    }
 }
 
 impl<E: EthSpec> ItemStore<E> for MemoryStore<E> {}
diff --git a/beacon_node/store/src/metadata.rs b/beacon_node/store/src/metadata.rs
index 3f076a767a..1d70e105b9 100644
--- a/beacon_node/store/src/metadata.rs
+++ b/beacon_node/store/src/metadata.rs
@@ -225,10 +225,10 @@ impl StoreItem for BlobInfo {
 pub struct DataColumnInfo {
     /// The slot after which data columns are or *will be* available (>=).
     ///
-    /// If this slot is in the future, then it is the first slot of the EIP-7594 fork, from which
+    /// If this slot is in the future, then it is the first slot of the Fulu fork, from which
     /// data columns will be available.
     ///
-    /// If the `oldest_data_column_slot` is `None` then this means that the EIP-7594 fork epoch is
+    /// If the `oldest_data_column_slot` is `None` then this means that the Fulu fork epoch is
     /// not yet known.
     pub oldest_data_column_slot: Option<Slot>,
 }
diff --git a/beacon_node/store/src/metrics.rs b/beacon_node/store/src/metrics.rs
index f0dd061790..6f9f667917 100644
--- a/beacon_node/store/src/metrics.rs
+++ b/beacon_node/store/src/metrics.rs
@@ -33,6 +33,13 @@ pub static DISK_DB_READ_BYTES: LazyLock<Result<IntCounterVec>> = LazyLock::new(|
         &["col"],
     )
 });
+pub static DISK_DB_KEY_READ_BYTES: LazyLock<Result<IntCounterVec>> = LazyLock::new(|| {
+    try_create_int_counter_vec(
+        "store_disk_db_key_read_bytes_total",
+        "Number of key bytes read from the hot on-disk DB",
+        &["col"],
+    )
+});
 pub static DISK_DB_READ_COUNT: LazyLock<Result<IntCounterVec>> = LazyLock::new(|| {
     try_create_int_counter_vec(
         "store_disk_db_read_count_total",
@@ -40,6 +47,13 @@ pub static DISK_DB_READ_COUNT: LazyLock<Result<IntCounterVec>> = LazyLock::new(|
         &["col"],
     )
 });
+pub static DISK_DB_KEY_READ_COUNT: LazyLock<Result<IntCounterVec>> = LazyLock::new(|| {
+    try_create_int_counter_vec(
+        "store_disk_db_read_count_total",
+        "Total number of key reads to the hot on-disk DB",
+        &["col"],
+    )
+});
 pub static DISK_DB_WRITE_COUNT: LazyLock<Result<IntCounterVec>> = LazyLock::new(|| {
     try_create_int_counter_vec(
         "store_disk_db_write_count_total",
@@ -66,6 +80,12 @@ pub static DISK_DB_EXISTS_COUNT: LazyLock<Result<IntCounterVec>> = LazyLock::new
         &["col"],
     )
 });
+pub static DISK_DB_DELETE_TIMES: LazyLock<Result<Histogram>> = LazyLock::new(|| {
+    try_create_histogram(
+        "store_disk_db_delete_seconds",
+        "Time taken to delete bytes from the store.",
+    )
+});
 pub static DISK_DB_DELETE_COUNT: LazyLock<Result<IntCounterVec>> = LazyLock::new(|| {
     try_create_int_counter_vec(
         "store_disk_db_delete_count_total",
@@ -73,6 +93,19 @@ pub static DISK_DB_DELETE_COUNT: LazyLock<Result<IntCounterVec>> = LazyLock::new
         &["col"],
     )
 });
+pub static DISK_DB_COMPACT_TIMES: LazyLock<Result<Histogram>> = LazyLock::new(|| {
+    try_create_histogram(
+        "store_disk_db_compact_seconds",
+        "Time taken to run compaction on the DB.",
+    )
+});
+pub static DISK_DB_TYPE: LazyLock<Result<IntCounterVec>> = LazyLock::new(|| {
+    try_create_int_counter_vec(
+        "store_disk_db_type",
+        "The on-disk database type being used",
+        &["db_type"],
+    )
+});
 /*
  * Anchor Info
  */
diff --git a/beacon_node/store/src/partial_beacon_state.rs b/beacon_node/store/src/partial_beacon_state.rs
index 22eecdcc60..d209512159 100644
--- a/beacon_node/store/src/partial_beacon_state.rs
+++ b/beacon_node/store/src/partial_beacon_state.rs
@@ -2,8 +2,8 @@ use crate::chunked_vector::{
     load_variable_list_from_db, load_vector_from_db, BlockRootsChunked, HistoricalRoots,
     HistoricalSummaries, RandaoMixes, StateRootsChunked,
 };
-use crate::{Error, KeyValueStore};
-use ssz::{Decode, DecodeError};
+use crate::{DBColumn, Error, KeyValueStore, KeyValueStoreOp};
+use ssz::{Decode, DecodeError, Encode};
 use ssz_derive::{Decode, Encode};
 use std::sync::Arc;
 use types::historical_summary::HistoricalSummary;
@@ -16,7 +16,7 @@ use types::*;
 ///
 /// This can be deleted once schema versions prior to V22 are no longer supported.
 #[superstruct(
-    variants(Base, Altair, Bellatrix, Capella, Deneb, Electra),
+    variants(Base, Altair, Bellatrix, Capella, Deneb, Electra, Fulu),
     variant_attributes(derive(Debug, PartialEq, Clone, Encode, Decode))
 )]
 #[derive(Debug, PartialEq, Clone, Encode)]
@@ -68,9 +68,9 @@ where
     pub current_epoch_attestations: List<PendingAttestation<E>, E::MaxPendingAttestations>,
 
     // Participation (Altair and later)
-    #[superstruct(only(Altair, Bellatrix, Capella, Deneb, Electra))]
+    #[superstruct(only(Altair, Bellatrix, Capella, Deneb, Electra, Fulu))]
     pub previous_epoch_participation: List<ParticipationFlags, E::ValidatorRegistryLimit>,
-    #[superstruct(only(Altair, Bellatrix, Capella, Deneb, Electra))]
+    #[superstruct(only(Altair, Bellatrix, Capella, Deneb, Electra, Fulu))]
     pub current_epoch_participation: List<ParticipationFlags, E::ValidatorRegistryLimit>,
 
     // Finality
@@ -80,13 +80,13 @@ where
     pub finalized_checkpoint: Checkpoint,
 
     // Inactivity
-    #[superstruct(only(Altair, Bellatrix, Capella, Deneb, Electra))]
+    #[superstruct(only(Altair, Bellatrix, Capella, Deneb, Electra, Fulu))]
     pub inactivity_scores: List<u64, E::ValidatorRegistryLimit>,
 
     // Light-client sync committees
-    #[superstruct(only(Altair, Bellatrix, Capella, Deneb, Electra))]
+    #[superstruct(only(Altair, Bellatrix, Capella, Deneb, Electra, Fulu))]
     pub current_sync_committee: Arc<SyncCommittee<E>>,
-    #[superstruct(only(Altair, Bellatrix, Capella, Deneb, Electra))]
+    #[superstruct(only(Altair, Bellatrix, Capella, Deneb, Electra, Fulu))]
     pub next_sync_committee: Arc<SyncCommittee<E>>,
 
     // Execution
@@ -110,37 +110,42 @@ where
         partial_getter(rename = "latest_execution_payload_header_electra")
     )]
     pub latest_execution_payload_header: ExecutionPayloadHeaderElectra<E>,
+    #[superstruct(
+        only(Fulu),
+        partial_getter(rename = "latest_execution_payload_header_fulu")
+    )]
+    pub latest_execution_payload_header: ExecutionPayloadHeaderFulu<E>,
 
     // Capella
-    #[superstruct(only(Capella, Deneb, Electra))]
+    #[superstruct(only(Capella, Deneb, Electra, Fulu))]
     pub next_withdrawal_index: u64,
-    #[superstruct(only(Capella, Deneb, Electra))]
+    #[superstruct(only(Capella, Deneb, Electra, Fulu))]
     pub next_withdrawal_validator_index: u64,
 
     #[ssz(skip_serializing, skip_deserializing)]
-    #[superstruct(only(Capella, Deneb, Electra))]
+    #[superstruct(only(Capella, Deneb, Electra, Fulu))]
     pub historical_summaries: Option<List<HistoricalSummary, E::HistoricalRootsLimit>>,
 
     // Electra
-    #[superstruct(only(Electra))]
+    #[superstruct(only(Electra, Fulu))]
     pub deposit_requests_start_index: u64,
-    #[superstruct(only(Electra))]
+    #[superstruct(only(Electra, Fulu))]
     pub deposit_balance_to_consume: u64,
-    #[superstruct(only(Electra))]
+    #[superstruct(only(Electra, Fulu))]
     pub exit_balance_to_consume: u64,
-    #[superstruct(only(Electra))]
+    #[superstruct(only(Electra, Fulu))]
     pub earliest_exit_epoch: Epoch,
-    #[superstruct(only(Electra))]
+    #[superstruct(only(Electra, Fulu))]
     pub consolidation_balance_to_consume: u64,
-    #[superstruct(only(Electra))]
+    #[superstruct(only(Electra, Fulu))]
     pub earliest_consolidation_epoch: Epoch,
 
-    #[superstruct(only(Electra))]
+    #[superstruct(only(Electra, Fulu))]
     pub pending_deposits: List<PendingDeposit, E::PendingDepositsLimit>,
-    #[superstruct(only(Electra))]
+    #[superstruct(only(Electra, Fulu))]
     pub pending_partial_withdrawals:
         List<PendingPartialWithdrawal, E::PendingPartialWithdrawalsLimit>,
-    #[superstruct(only(Electra))]
+    #[superstruct(only(Electra, Fulu))]
     pub pending_consolidations: List<PendingConsolidation, E::PendingConsolidationsLimit>,
 }
 
@@ -167,6 +172,15 @@ impl<E: EthSpec> PartialBeaconState<E> {
         ))
     }
 
+    /// Prepare the partial state for storage in the KV database.
+    pub fn as_kv_store_op(&self, state_root: Hash256) -> KeyValueStoreOp {
+        KeyValueStoreOp::PutKeyValue(
+            DBColumn::BeaconState,
+            state_root.as_slice().to_vec(),
+            self.as_ssz_bytes(),
+        )
+    }
+
     pub fn load_block_roots<S: KeyValueStore<E>>(
         &mut self,
         store: &S,
@@ -409,6 +423,31 @@ impl<E: EthSpec> TryInto<BeaconState<E>> for PartialBeaconState<E> {
                 ],
                 [historical_summaries]
             ),
+            PartialBeaconState::Fulu(inner) => impl_try_into_beacon_state!(
+                inner,
+                Fulu,
+                BeaconStateFulu,
+                [
+                    previous_epoch_participation,
+                    current_epoch_participation,
+                    current_sync_committee,
+                    next_sync_committee,
+                    inactivity_scores,
+                    latest_execution_payload_header,
+                    next_withdrawal_index,
+                    next_withdrawal_validator_index,
+                    deposit_requests_start_index,
+                    deposit_balance_to_consume,
+                    exit_balance_to_consume,
+                    earliest_exit_epoch,
+                    consolidation_balance_to_consume,
+                    earliest_consolidation_epoch,
+                    pending_deposits,
+                    pending_partial_withdrawals,
+                    pending_consolidations
+                ],
+                [historical_summaries]
+            ),
         };
         Ok(state)
     }
diff --git a/beacon_node/store/src/reconstruct.rs b/beacon_node/store/src/reconstruct.rs
index 9bec83a35c..2a3b208aae 100644
--- a/beacon_node/store/src/reconstruct.rs
+++ b/beacon_node/store/src/reconstruct.rs
@@ -111,7 +111,7 @@ where
                 self.store_cold_state(&state_root, &state, &mut io_batch)?;
 
                 let batch_complete =
-                    num_blocks.map_or(false, |n_blocks| slot == lower_limit_slot + n_blocks as u64);
+                    num_blocks.is_some_and(|n_blocks| slot == lower_limit_slot + n_blocks as u64);
                 let reconstruction_complete = slot + 1 == upper_limit_slot;
 
                 // Commit the I/O batch if:
diff --git a/beacon_node/store/src/state_cache.rs b/beacon_node/store/src/state_cache.rs
index 5c1faa7f2f..96e4de4639 100644
--- a/beacon_node/store/src/state_cache.rs
+++ b/beacon_node/store/src/state_cache.rs
@@ -77,9 +77,7 @@ impl<E: EthSpec> StateCache<E> {
         if self
             .finalized_state
             .as_ref()
-            .map_or(false, |finalized_state| {
-                state.slot() < finalized_state.state.slot()
-            })
+            .is_some_and(|finalized_state| state.slot() < finalized_state.state.slot())
         {
             return Err(Error::FinalizedStateDecreasingSlot);
         }
@@ -127,9 +125,7 @@ impl<E: EthSpec> StateCache<E> {
         if self
             .finalized_state
             .as_ref()
-            .map_or(false, |finalized_state| {
-                finalized_state.state_root == state_root
-            })
+            .is_some_and(|finalized_state| finalized_state.state_root == state_root)
         {
             return Ok(PutStateOutcome::Finalized);
         }
diff --git a/book/src/help_bn.md b/book/src/help_bn.md
index a4ab44748c..2d12010094 100644
--- a/book/src/help_bn.md
+++ b/book/src/help_bn.md
@@ -11,6 +11,9 @@ Options:
       --auto-compact-db <auto-compact-db>
           Enable or disable automatic compaction of the database on
           finalization. [default: true]
+      --beacon-node-backend <DATABASE>
+          Set the database backend to be used by the beacon node. [possible
+          values: leveldb]
       --blob-prune-margin-epochs <EPOCHS>
           The margin for blob pruning in epochs. The oldest blobs are pruned up
           until data_availability_boundary - blob_prune_margin_epochs. [default:
diff --git a/book/src/installation-source.md b/book/src/installation-source.md
index 3c9f27d236..19098a5bc8 100644
--- a/book/src/installation-source.md
+++ b/book/src/installation-source.md
@@ -154,7 +154,7 @@ You can customise the features that Lighthouse is built with using the `FEATURES
 variable. E.g.
 
 ```
-FEATURES=gnosis,slasher-lmdb make
+FEATURES=gnosis,slasher-lmdb,beacon-node-leveldb make
 ```
 
 Commonly used features include:
@@ -163,11 +163,12 @@ Commonly used features include:
 - `portable`: the default feature as Lighthouse now uses runtime detection of hardware CPU features.
 - `slasher-lmdb`: support for the LMDB slasher backend. Enabled by default.
 - `slasher-mdbx`: support for the MDBX slasher backend.
+- `beacon-node-leveldb`: support for the leveldb backend. Enabled by default.
 - `jemalloc`: use [`jemalloc`][jemalloc] to allocate memory. Enabled by default on Linux and macOS.
   Not supported on Windows.
 - `spec-minimal`: support for the minimal preset (useful for testing).
 
-Default features (e.g. `slasher-lmdb`) may be opted out of using the `--no-default-features`
+Default features (e.g. `slasher-lmdb`, `beacon-node-leveldb`) may be opted out of using the `--no-default-features`
 argument for `cargo`, which can be plumbed in via the `CARGO_INSTALL_EXTRA_FLAGS` environment variable.
 E.g.
 
diff --git a/common/account_utils/Cargo.toml b/common/account_utils/Cargo.toml
index dece975d37..3ab6034688 100644
--- a/common/account_utils/Cargo.toml
+++ b/common/account_utils/Cargo.toml
@@ -6,7 +6,6 @@ edition = { workspace = true }
 # See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
 
 [dependencies]
-directory = { workspace = true }
 eth2_keystore = { workspace = true }
 eth2_wallet = { workspace = true }
 filesystem = { workspace = true }
diff --git a/common/account_utils/src/validator_definitions.rs b/common/account_utils/src/validator_definitions.rs
index a4850fc1c6..7337d6dfb4 100644
--- a/common/account_utils/src/validator_definitions.rs
+++ b/common/account_utils/src/validator_definitions.rs
@@ -4,13 +4,12 @@
 //! attempt) to load into the `crate::intialized_validators::InitializedValidators` struct.
 
 use crate::{default_keystore_password_path, read_password_string, write_file_via_temporary};
-use directory::ensure_dir_exists;
 use eth2_keystore::Keystore;
 use regex::Regex;
 use serde::{Deserialize, Serialize};
 use slog::{error, Logger};
 use std::collections::HashSet;
-use std::fs::{self, File};
+use std::fs::{self, create_dir_all, File};
 use std::io;
 use std::path::{Path, PathBuf};
 use types::{graffiti::GraffitiString, Address, PublicKey};
@@ -229,7 +228,7 @@ impl From<Vec<ValidatorDefinition>> for ValidatorDefinitions {
 impl ValidatorDefinitions {
     /// Open an existing file or create a new, empty one if it does not exist.
     pub fn open_or_create<P: AsRef<Path>>(validators_dir: P) -> Result<Self, Error> {
-        ensure_dir_exists(validators_dir.as_ref()).map_err(|_| {
+        create_dir_all(validators_dir.as_ref()).map_err(|_| {
             Error::UnableToCreateValidatorDir(PathBuf::from(validators_dir.as_ref()))
         })?;
         let config_path = validators_dir.as_ref().join(CONFIG_FILENAME);
@@ -435,7 +434,7 @@ pub fn recursively_find_voting_keystores<P: AsRef<Path>>(
             && dir_entry
                 .file_name()
                 .to_str()
-                .map_or(false, is_voting_keystore)
+                .is_some_and(is_voting_keystore)
         {
             matches.push(dir_entry.path())
         }
diff --git a/common/directory/src/lib.rs b/common/directory/src/lib.rs
index df03b4f9a4..d042f8dfad 100644
--- a/common/directory/src/lib.rs
+++ b/common/directory/src/lib.rs
@@ -1,6 +1,6 @@
 use clap::ArgMatches;
 pub use eth2_network_config::DEFAULT_HARDCODED_NETWORK;
-use std::fs::{self, create_dir_all};
+use std::fs;
 use std::path::{Path, PathBuf};
 
 /// Names for the default directories.
@@ -30,17 +30,6 @@ pub fn get_network_dir(matches: &ArgMatches) -> String {
     }
 }
 
-/// Checks if a directory exists in the given path and creates a directory if it does not exist.
-pub fn ensure_dir_exists<P: AsRef<Path>>(path: P) -> Result<(), String> {
-    let path = path.as_ref();
-
-    if !path.exists() {
-        create_dir_all(path).map_err(|e| format!("Unable to create {:?}: {:?}", path, e))?;
-    }
-
-    Ok(())
-}
-
 /// If `arg` is in `matches`, parses the value as a path.
 ///
 /// Otherwise, attempts to find the default directory for the `testnet` from the `matches`.
diff --git a/common/eth2/Cargo.toml b/common/eth2/Cargo.toml
index 9d6dea100d..a1bc9d025b 100644
--- a/common/eth2/Cargo.toml
+++ b/common/eth2/Cargo.toml
@@ -7,6 +7,7 @@ edition = { workspace = true }
 
 [dependencies]
 derivative = { workspace = true }
+either = { workspace = true }
 eth2_keystore = { workspace = true }
 ethereum_serde_utils = { workspace = true }
 ethereum_ssz = { workspace = true }
@@ -31,10 +32,6 @@ zeroize = { workspace = true }
 [dev-dependencies]
 tokio = { workspace = true }
 
-[target.'cfg(target_os = "linux")'.dependencies]
-psutil = { version = "3.3.0", optional = true }
-procfs = { version = "0.15.1", optional = true }
-
 [features]
 default = ["lighthouse"]
-lighthouse = ["psutil", "procfs"]
+lighthouse = []
diff --git a/common/eth2/src/lib.rs b/common/eth2/src/lib.rs
index 9bb91b1543..b94115ced3 100644
--- a/common/eth2/src/lib.rs
+++ b/common/eth2/src/lib.rs
@@ -17,6 +17,7 @@ pub mod types;
 use self::mixin::{RequestAccept, ResponseOptional};
 use self::types::{Error as ResponseError, *};
 use derivative::Derivative;
+use either::Either;
 use futures::Stream;
 use futures_util::StreamExt;
 use lighthouse_network::PeerId;
@@ -1330,7 +1331,7 @@ impl BeaconNodeHttpClient {
     /// `POST v2/beacon/pool/attestations`
     pub async fn post_beacon_pool_attestations_v2<E: EthSpec>(
         &self,
-        attestations: &[Attestation<E>],
+        attestations: Either<Vec<Attestation<E>>, Vec<SingleAttestation>>,
         fork_name: ForkName,
     ) -> Result<(), Error> {
         let mut path = self.eth_path(V2)?;
@@ -1341,13 +1342,26 @@ impl BeaconNodeHttpClient {
             .push("pool")
             .push("attestations");
 
-        self.post_with_timeout_and_consensus_header(
-            path,
-            &attestations,
-            self.timeouts.attestation,
-            fork_name,
-        )
-        .await?;
+        match attestations {
+            Either::Right(attestations) => {
+                self.post_with_timeout_and_consensus_header(
+                    path,
+                    &attestations,
+                    self.timeouts.attestation,
+                    fork_name,
+                )
+                .await?;
+            }
+            Either::Left(attestations) => {
+                self.post_with_timeout_and_consensus_header(
+                    path,
+                    &attestations,
+                    self.timeouts.attestation,
+                    fork_name,
+                )
+                .await?;
+            }
+        };
 
         Ok(())
     }
diff --git a/common/eth2/src/lighthouse.rs b/common/eth2/src/lighthouse.rs
index 66dd5d779b..badc4857c4 100644
--- a/common/eth2/src/lighthouse.rs
+++ b/common/eth2/src/lighthouse.rs
@@ -88,12 +88,6 @@ pub struct ValidatorInclusionData {
     pub is_previous_epoch_head_attester: bool,
 }
 
-#[cfg(target_os = "linux")]
-use {
-    psutil::cpu::os::linux::CpuTimesExt, psutil::memory::os::linux::VirtualMemoryExt,
-    psutil::process::Process,
-};
-
 /// Reports on the health of the Lighthouse instance.
 #[derive(Clone, Debug, PartialEq, Serialize, Deserialize)]
 pub struct Health {
@@ -164,69 +158,6 @@ pub struct SystemHealth {
     pub misc_os: String,
 }
 
-impl SystemHealth {
-    #[cfg(not(target_os = "linux"))]
-    pub fn observe() -> Result<Self, String> {
-        Err("Health is only available on Linux".into())
-    }
-
-    #[cfg(target_os = "linux")]
-    pub fn observe() -> Result<Self, String> {
-        let vm = psutil::memory::virtual_memory()
-            .map_err(|e| format!("Unable to get virtual memory: {:?}", e))?;
-        let loadavg =
-            psutil::host::loadavg().map_err(|e| format!("Unable to get loadavg: {:?}", e))?;
-
-        let cpu =
-            psutil::cpu::cpu_times().map_err(|e| format!("Unable to get cpu times: {:?}", e))?;
-
-        let disk_usage = psutil::disk::disk_usage("/")
-            .map_err(|e| format!("Unable to disk usage info: {:?}", e))?;
-
-        let disk = psutil::disk::DiskIoCountersCollector::default()
-            .disk_io_counters()
-            .map_err(|e| format!("Unable to get disk counters: {:?}", e))?;
-
-        let net = psutil::network::NetIoCountersCollector::default()
-            .net_io_counters()
-            .map_err(|e| format!("Unable to get network io counters: {:?}", e))?;
-
-        let boot_time = psutil::host::boot_time()
-            .map_err(|e| format!("Unable to get system boot time: {:?}", e))?
-            .duration_since(std::time::UNIX_EPOCH)
-            .map_err(|e| format!("Boot time is lower than unix epoch: {}", e))?
-            .as_secs();
-
-        Ok(Self {
-            sys_virt_mem_total: vm.total(),
-            sys_virt_mem_available: vm.available(),
-            sys_virt_mem_used: vm.used(),
-            sys_virt_mem_free: vm.free(),
-            sys_virt_mem_cached: vm.cached(),
-            sys_virt_mem_buffers: vm.buffers(),
-            sys_virt_mem_percent: vm.percent(),
-            sys_loadavg_1: loadavg.one,
-            sys_loadavg_5: loadavg.five,
-            sys_loadavg_15: loadavg.fifteen,
-            cpu_cores: psutil::cpu::cpu_count_physical(),
-            cpu_threads: psutil::cpu::cpu_count(),
-            system_seconds_total: cpu.system().as_secs(),
-            cpu_time_total: cpu.total().as_secs(),
-            user_seconds_total: cpu.user().as_secs(),
-            iowait_seconds_total: cpu.iowait().as_secs(),
-            idle_seconds_total: cpu.idle().as_secs(),
-            disk_node_bytes_total: disk_usage.total(),
-            disk_node_bytes_free: disk_usage.free(),
-            disk_node_reads_total: disk.read_count(),
-            disk_node_writes_total: disk.write_count(),
-            network_node_bytes_total_received: net.bytes_recv(),
-            network_node_bytes_total_transmit: net.bytes_sent(),
-            misc_node_boot_ts_seconds: boot_time,
-            misc_os: std::env::consts::OS.to_string(),
-        })
-    }
-}
-
 /// Process specific health
 #[derive(Clone, Debug, PartialEq, Serialize, Deserialize)]
 pub struct ProcessHealth {
@@ -244,59 +175,6 @@ pub struct ProcessHealth {
     pub pid_process_seconds_total: u64,
 }
 
-impl ProcessHealth {
-    #[cfg(not(target_os = "linux"))]
-    pub fn observe() -> Result<Self, String> {
-        Err("Health is only available on Linux".into())
-    }
-
-    #[cfg(target_os = "linux")]
-    pub fn observe() -> Result<Self, String> {
-        let process =
-            Process::current().map_err(|e| format!("Unable to get current process: {:?}", e))?;
-
-        let process_mem = process
-            .memory_info()
-            .map_err(|e| format!("Unable to get process memory info: {:?}", e))?;
-
-        let me = procfs::process::Process::myself()
-            .map_err(|e| format!("Unable to get process: {:?}", e))?;
-        let stat = me
-            .stat()
-            .map_err(|e| format!("Unable to get stat: {:?}", e))?;
-
-        let process_times = process
-            .cpu_times()
-            .map_err(|e| format!("Unable to get process cpu times : {:?}", e))?;
-
-        Ok(Self {
-            pid: process.pid(),
-            pid_num_threads: stat.num_threads,
-            pid_mem_resident_set_size: process_mem.rss(),
-            pid_mem_virtual_memory_size: process_mem.vms(),
-            pid_mem_shared_memory_size: process_mem.shared(),
-            pid_process_seconds_total: process_times.busy().as_secs()
-                + process_times.children_system().as_secs()
-                + process_times.children_system().as_secs(),
-        })
-    }
-}
-
-impl Health {
-    #[cfg(not(target_os = "linux"))]
-    pub fn observe() -> Result<Self, String> {
-        Err("Health is only available on Linux".into())
-    }
-
-    #[cfg(target_os = "linux")]
-    pub fn observe() -> Result<Self, String> {
-        Ok(Self {
-            process: ProcessHealth::observe()?,
-            system: SystemHealth::observe()?,
-        })
-    }
-}
-
 /// Indicates how up-to-date the Eth1 caches are.
 #[derive(Clone, Debug, PartialEq, Serialize, Deserialize)]
 pub struct Eth1SyncStatusData {
diff --git a/common/eth2/src/types.rs b/common/eth2/src/types.rs
index 68e6a927c7..202cd36f81 100644
--- a/common/eth2/src/types.rs
+++ b/common/eth2/src/types.rs
@@ -584,12 +584,20 @@ pub struct IdentityData {
     pub metadata: MetaData,
 }
 
+#[superstruct(
+    variants(V2, V3),
+    variant_attributes(derive(Clone, Debug, PartialEq, Serialize, Deserialize))
+)]
 #[derive(Debug, Clone, PartialEq, Serialize, Deserialize)]
+#[serde(untagged)]
 pub struct MetaData {
     #[serde(with = "serde_utils::quoted_u64")]
     pub seq_number: u64,
     pub attnets: String,
     pub syncnets: String,
+    #[superstruct(only(V3))]
+    #[serde(with = "serde_utils::quoted_u64")]
+    pub custody_group_count: u64,
 }
 
 #[derive(Debug, Clone, PartialEq, Serialize, Deserialize)]
@@ -1091,6 +1099,9 @@ impl ForkVersionDeserialize for SsePayloadAttributes {
             ForkName::Electra => serde_json::from_value(value)
                 .map(Self::V3)
                 .map_err(serde::de::Error::custom),
+            ForkName::Fulu => serde_json::from_value(value)
+                .map(Self::V3)
+                .map_err(serde::de::Error::custom),
             ForkName::Base | ForkName::Altair => Err(serde::de::Error::custom(format!(
                 "SsePayloadAttributes deserialization for {fork_name} not implemented"
             ))),
@@ -1123,6 +1134,7 @@ impl ForkVersionDeserialize for SseExtendedPayloadAttributes {
 #[serde(bound = "E: EthSpec", untagged)]
 pub enum EventKind<E: EthSpec> {
     Attestation(Box<Attestation<E>>),
+    SingleAttestation(Box<SingleAttestation>),
     Block(SseBlock),
     BlobSidecar(SseBlobSidecar),
     FinalizedCheckpoint(SseFinalizedCheckpoint),
@@ -1149,6 +1161,7 @@ impl<E: EthSpec> EventKind<E> {
             EventKind::Block(_) => "block",
             EventKind::BlobSidecar(_) => "blob_sidecar",
             EventKind::Attestation(_) => "attestation",
+            EventKind::SingleAttestation(_) => "single_attestation",
             EventKind::VoluntaryExit(_) => "voluntary_exit",
             EventKind::FinalizedCheckpoint(_) => "finalized_checkpoint",
             EventKind::ChainReorg(_) => "chain_reorg",
@@ -1171,6 +1184,11 @@ impl<E: EthSpec> EventKind<E> {
             "attestation" => Ok(EventKind::Attestation(serde_json::from_str(data).map_err(
                 |e| ServerError::InvalidServerSentEvent(format!("Attestation: {:?}", e)),
             )?)),
+            "single_attestation" => Ok(EventKind::SingleAttestation(
+                serde_json::from_str(data).map_err(|e| {
+                    ServerError::InvalidServerSentEvent(format!("SingleAttestation: {:?}", e))
+                })?,
+            )),
             "block" => Ok(EventKind::Block(serde_json::from_str(data).map_err(
                 |e| ServerError::InvalidServerSentEvent(format!("Block: {:?}", e)),
             )?)),
@@ -1265,6 +1283,7 @@ pub enum EventTopic {
     Block,
     BlobSidecar,
     Attestation,
+    SingleAttestation,
     VoluntaryExit,
     FinalizedCheckpoint,
     ChainReorg,
@@ -1290,6 +1309,7 @@ impl FromStr for EventTopic {
             "block" => Ok(EventTopic::Block),
             "blob_sidecar" => Ok(EventTopic::BlobSidecar),
             "attestation" => Ok(EventTopic::Attestation),
+            "single_attestation" => Ok(EventTopic::SingleAttestation),
             "voluntary_exit" => Ok(EventTopic::VoluntaryExit),
             "finalized_checkpoint" => Ok(EventTopic::FinalizedCheckpoint),
             "chain_reorg" => Ok(EventTopic::ChainReorg),
@@ -1316,6 +1336,7 @@ impl fmt::Display for EventTopic {
             EventTopic::Block => write!(f, "block"),
             EventTopic::BlobSidecar => write!(f, "blob_sidecar"),
             EventTopic::Attestation => write!(f, "attestation"),
+            EventTopic::SingleAttestation => write!(f, "single_attestation"),
             EventTopic::VoluntaryExit => write!(f, "voluntary_exit"),
             EventTopic::FinalizedCheckpoint => write!(f, "finalized_checkpoint"),
             EventTopic::ChainReorg => write!(f, "chain_reorg"),
@@ -1874,14 +1895,10 @@ impl<E: EthSpec> PublishBlockRequest<E> {
 impl<E: EthSpec> TryFrom<Arc<SignedBeaconBlock<E>>> for PublishBlockRequest<E> {
     type Error = &'static str;
     fn try_from(block: Arc<SignedBeaconBlock<E>>) -> Result<Self, Self::Error> {
-        match *block {
-            SignedBeaconBlock::Base(_)
-            | SignedBeaconBlock::Altair(_)
-            | SignedBeaconBlock::Bellatrix(_)
-            | SignedBeaconBlock::Capella(_) => Ok(PublishBlockRequest::Block(block)),
-            SignedBeaconBlock::Deneb(_) | SignedBeaconBlock::Electra(_) => Err(
-                "post-Deneb block contents cannot be fully constructed from just the signed block",
-            ),
+        if block.message().fork_name_unchecked().deneb_enabled() {
+            Err("post-Deneb block contents cannot be fully constructed from just the signed block")
+        } else {
+            Ok(PublishBlockRequest::Block(block))
         }
     }
 }
@@ -1985,16 +2002,18 @@ impl<E: EthSpec> ForkVersionDeserialize for FullPayloadContents<E> {
         value: Value,
         fork_name: ForkName,
     ) -> Result<Self, D::Error> {
-        match fork_name {
-            ForkName::Bellatrix | ForkName::Capella => serde_json::from_value(value)
-                .map(Self::Payload)
-                .map_err(serde::de::Error::custom),
-            ForkName::Deneb | ForkName::Electra => serde_json::from_value(value)
+        if fork_name.deneb_enabled() {
+            serde_json::from_value(value)
                 .map(Self::PayloadAndBlobs)
-                .map_err(serde::de::Error::custom),
-            ForkName::Base | ForkName::Altair => Err(serde::de::Error::custom(format!(
+                .map_err(serde::de::Error::custom)
+        } else if fork_name.bellatrix_enabled() {
+            serde_json::from_value(value)
+                .map(Self::Payload)
+                .map_err(serde::de::Error::custom)
+        } else {
+            Err(serde::de::Error::custom(format!(
                 "FullPayloadContents deserialization for {fork_name} not implemented"
-            ))),
+            )))
         }
     }
 }
diff --git a/common/eth2_network_config/built_in_network_configs/chiado/config.yaml b/common/eth2_network_config/built_in_network_configs/chiado/config.yaml
index 1eca01bbee..35ba3af28b 100644
--- a/common/eth2_network_config/built_in_network_configs/chiado/config.yaml
+++ b/common/eth2_network_config/built_in_network_configs/chiado/config.yaml
@@ -15,7 +15,6 @@ TERMINAL_TOTAL_DIFFICULTY: 231707791542740786049188744689299064356246512
 TERMINAL_BLOCK_HASH: 0x0000000000000000000000000000000000000000000000000000000000000000
 TERMINAL_BLOCK_HASH_ACTIVATION_EPOCH: 18446744073709551615
 
-
 # Genesis
 # ---------------------------------------------------------------
 # *CUSTOM
@@ -27,7 +26,6 @@ GENESIS_FORK_VERSION: 0x0000006f
 # *CUSTOM
 GENESIS_DELAY: 300
 
-
 # Forking
 # ---------------------------------------------------------------
 # Some forks are disabled for now:
@@ -49,6 +47,9 @@ DENEB_FORK_EPOCH: 516608 # Wed Jan 31 2024 18:15:40 GMT+0000
 # Electra
 ELECTRA_FORK_VERSION: 0x0500006f
 ELECTRA_FORK_EPOCH: 18446744073709551615
+# Fulu
+FULU_FORK_VERSION: 0x0600006f
+FULU_FORK_EPOCH: 18446744073709551615
 
 # Time parameters
 # ---------------------------------------------------------------
@@ -63,7 +64,6 @@ SHARD_COMMITTEE_PERIOD: 256
 # 2**10 (= 1024) ~1.4 hour
 ETH1_FOLLOW_DISTANCE: 1024
 
-
 # Validator cycle
 # ---------------------------------------------------------------
 # 2**2 (= 4)
@@ -90,7 +90,6 @@ REORG_PARENT_WEIGHT_THRESHOLD: 160
 # `2` epochs
 REORG_MAX_EPOCHS_SINCE_FINALIZATION: 2
 
-
 # Deposit contract
 # ---------------------------------------------------------------
 # xDai Mainnet
@@ -136,9 +135,12 @@ MAX_REQUEST_BLOB_SIDECARS: 768
 MIN_EPOCHS_FOR_BLOB_SIDECARS_REQUESTS: 16384
 # `6`
 BLOB_SIDECAR_SUBNET_COUNT: 6
+# `uint64(6)`
+MAX_BLOBS_PER_BLOCK: 6
 
 # DAS
-CUSTODY_REQUIREMENT: 4
-DATA_COLUMN_SIDECAR_SUBNET_COUNT: 128
 NUMBER_OF_COLUMNS: 128
-SAMPLES_PER_SLOT: 8
\ No newline at end of file
+NUMBER_OF_CUSTODY_GROUPS: 128
+DATA_COLUMN_SIDECAR_SUBNET_COUNT: 128
+SAMPLES_PER_SLOT: 8
+CUSTODY_REQUIREMENT: 4
diff --git a/common/eth2_network_config/built_in_network_configs/gnosis/config.yaml b/common/eth2_network_config/built_in_network_configs/gnosis/config.yaml
index 500555a269..9ff5a16198 100644
--- a/common/eth2_network_config/built_in_network_configs/gnosis/config.yaml
+++ b/common/eth2_network_config/built_in_network_configs/gnosis/config.yaml
@@ -23,7 +23,6 @@ GENESIS_FORK_VERSION: 0x00000064
 # 6000 seconds (100 minutes)
 GENESIS_DELAY: 6000
 
-
 # Forking
 # ---------------------------------------------------------------
 # Some forks are disabled for now:
@@ -45,7 +44,9 @@ DENEB_FORK_EPOCH: 889856 # 2024-03-11T18:30:20.000Z
 # Electra
 ELECTRA_FORK_VERSION: 0x05000064
 ELECTRA_FORK_EPOCH: 18446744073709551615
-
+# Fulu
+FULU_FORK_VERSION: 0x06000064
+FULU_FORK_EPOCH: 18446744073709551615
 
 # Time parameters
 # ---------------------------------------------------------------
@@ -60,7 +61,6 @@ SHARD_COMMITTEE_PERIOD: 256
 # 2**10 (= 1024) ~1.4 hour
 ETH1_FOLLOW_DISTANCE: 1024
 
-
 # Validator cycle
 # ---------------------------------------------------------------
 # 2**2 (= 4)
@@ -76,7 +76,6 @@ MAX_PER_EPOCH_ACTIVATION_CHURN_LIMIT: 2
 # 2**12 (= 4096)
 CHURN_LIMIT_QUOTIENT: 4096
 
-
 # Fork choice
 # ---------------------------------------------------------------
 # 40%
@@ -119,9 +118,12 @@ MAX_REQUEST_BLOB_SIDECARS: 768
 MIN_EPOCHS_FOR_BLOB_SIDECARS_REQUESTS: 16384
 # `6`
 BLOB_SIDECAR_SUBNET_COUNT: 6
+# `uint64(6)`
+MAX_BLOBS_PER_BLOCK: 6
 
 # DAS
-CUSTODY_REQUIREMENT: 4
-DATA_COLUMN_SIDECAR_SUBNET_COUNT: 128
 NUMBER_OF_COLUMNS: 128
-SAMPLES_PER_SLOT: 8
\ No newline at end of file
+NUMBER_OF_CUSTODY_GROUPS: 128
+DATA_COLUMN_SIDECAR_SUBNET_COUNT: 128
+SAMPLES_PER_SLOT: 8
+CUSTODY_REQUIREMENT: 4
diff --git a/common/eth2_network_config/built_in_network_configs/holesky/config.yaml b/common/eth2_network_config/built_in_network_configs/holesky/config.yaml
index d67d77d3be..d0b61422e0 100644
--- a/common/eth2_network_config/built_in_network_configs/holesky/config.yaml
+++ b/common/eth2_network_config/built_in_network_configs/holesky/config.yaml
@@ -12,7 +12,6 @@ GENESIS_FORK_VERSION: 0x01017000
 # Genesis delay 5 mins
 GENESIS_DELAY: 300
 
-
 # Forking
 # ---------------------------------------------------------------
 # Some forks are disabled for now:
@@ -37,6 +36,9 @@ DENEB_FORK_EPOCH: 29696
 # Electra
 ELECTRA_FORK_VERSION: 0x06017000
 ELECTRA_FORK_EPOCH: 18446744073709551615
+# Fulu
+FULU_FORK_VERSION: 0x07017000
+FULU_FORK_EPOCH: 18446744073709551615
 
 # Time parameters
 # ---------------------------------------------------------------
@@ -51,7 +53,6 @@ SHARD_COMMITTEE_PERIOD: 256
 # 2**11 (= 2,048) Eth1 blocks ~8 hours
 ETH1_FOLLOW_DISTANCE: 2048
 
-
 # Validator cycle
 # ---------------------------------------------------------------
 # 2**2 (= 4)
@@ -123,9 +124,12 @@ MAX_REQUEST_BLOB_SIDECARS: 768
 MIN_EPOCHS_FOR_BLOB_SIDECARS_REQUESTS: 4096
 # `6`
 BLOB_SIDECAR_SUBNET_COUNT: 6
+# `uint64(6)`
+MAX_BLOBS_PER_BLOCK: 6
 
 # DAS
-CUSTODY_REQUIREMENT: 4
-DATA_COLUMN_SIDECAR_SUBNET_COUNT: 128
 NUMBER_OF_COLUMNS: 128
-SAMPLES_PER_SLOT: 8
\ No newline at end of file
+NUMBER_OF_CUSTODY_GROUPS: 128
+DATA_COLUMN_SIDECAR_SUBNET_COUNT: 128
+SAMPLES_PER_SLOT: 8
+CUSTODY_REQUIREMENT: 4
diff --git a/common/eth2_network_config/built_in_network_configs/mainnet/config.yaml b/common/eth2_network_config/built_in_network_configs/mainnet/config.yaml
index 18591fecdc..74fe727867 100644
--- a/common/eth2_network_config/built_in_network_configs/mainnet/config.yaml
+++ b/common/eth2_network_config/built_in_network_configs/mainnet/config.yaml
@@ -18,8 +18,6 @@ TERMINAL_TOTAL_DIFFICULTY: 58750000000000000000000
 TERMINAL_BLOCK_HASH: 0x0000000000000000000000000000000000000000000000000000000000000000
 TERMINAL_BLOCK_HASH_ACTIVATION_EPOCH: 18446744073709551615
 
-
-
 # Genesis
 # ---------------------------------------------------------------
 # `2**14` (= 16,384)
@@ -31,7 +29,6 @@ GENESIS_FORK_VERSION: 0x00000000
 # 604800 seconds (7 days)
 GENESIS_DELAY: 604800
 
-
 # Forking
 # ---------------------------------------------------------------
 # Some forks are disabled for now:
@@ -40,22 +37,22 @@ GENESIS_DELAY: 604800
 
 # Altair
 ALTAIR_FORK_VERSION: 0x01000000
-ALTAIR_FORK_EPOCH: 74240  # Oct 27, 2021, 10:56:23am UTC
+ALTAIR_FORK_EPOCH: 74240 # Oct 27, 2021, 10:56:23am UTC
 # Bellatrix
 BELLATRIX_FORK_VERSION: 0x02000000
-BELLATRIX_FORK_EPOCH: 144896  # Sept 6, 2022, 11:34:47am UTC
+BELLATRIX_FORK_EPOCH: 144896 # Sept 6, 2022, 11:34:47am UTC
 # Capella
 CAPELLA_FORK_VERSION: 0x03000000
-CAPELLA_FORK_EPOCH: 194048  # April 12, 2023, 10:27:35pm UTC
+CAPELLA_FORK_EPOCH: 194048 # April 12, 2023, 10:27:35pm UTC
 # Deneb
 DENEB_FORK_VERSION: 0x04000000
-DENEB_FORK_EPOCH: 269568  # March 13, 2024, 01:55:35pm UTC
+DENEB_FORK_EPOCH: 269568 # March 13, 2024, 01:55:35pm UTC
 # Electra
 ELECTRA_FORK_VERSION: 0x05000000
 ELECTRA_FORK_EPOCH: 18446744073709551615
-# PeerDAS
-EIP7594_FORK_EPOCH: 18446744073709551615
-
+# Fulu
+FULU_FORK_VERSION: 0x06000000
+FULU_FORK_EPOCH: 18446744073709551615
 
 # Time parameters
 # ---------------------------------------------------------------
@@ -70,7 +67,6 @@ SHARD_COMMITTEE_PERIOD: 256
 # 2**11 (= 2,048) Eth1 blocks ~8 hours
 ETH1_FOLLOW_DISTANCE: 2048
 
-
 # Validator cycle
 # ---------------------------------------------------------------
 # 2**2 (= 4)
@@ -97,7 +93,6 @@ REORG_PARENT_WEIGHT_THRESHOLD: 160
 # `2` epochs
 REORG_MAX_EPOCHS_SINCE_FINALIZATION: 2
 
-
 # Deposit contract
 # ---------------------------------------------------------------
 # Ethereum PoW Mainnet
@@ -105,7 +100,6 @@ DEPOSIT_CHAIN_ID: 1
 DEPOSIT_NETWORK_ID: 1
 DEPOSIT_CONTRACT_ADDRESS: 0x00000000219ab540356cBB839Cbe05303d7705Fa
 
-
 # Networking
 # ---------------------------------------------------------------
 # `10 * 2**20` (= 10485760, 10 MiB)
@@ -145,9 +139,12 @@ MAX_REQUEST_BLOB_SIDECARS: 768
 MIN_EPOCHS_FOR_BLOB_SIDECARS_REQUESTS: 4096
 # `6`
 BLOB_SIDECAR_SUBNET_COUNT: 6
+# `uint64(6)`
+MAX_BLOBS_PER_BLOCK: 6
 
 # DAS
-CUSTODY_REQUIREMENT: 4
-DATA_COLUMN_SIDECAR_SUBNET_COUNT: 128
 NUMBER_OF_COLUMNS: 128
-SAMPLES_PER_SLOT: 8
\ No newline at end of file
+NUMBER_OF_CUSTODY_GROUPS: 128
+DATA_COLUMN_SIDECAR_SUBNET_COUNT: 128
+SAMPLES_PER_SLOT: 8
+CUSTODY_REQUIREMENT: 4
diff --git a/common/eth2_network_config/built_in_network_configs/sepolia/config.yaml b/common/eth2_network_config/built_in_network_configs/sepolia/config.yaml
index b08a6180bf..7564d8f0f6 100644
--- a/common/eth2_network_config/built_in_network_configs/sepolia/config.yaml
+++ b/common/eth2_network_config/built_in_network_configs/sepolia/config.yaml
@@ -119,9 +119,12 @@ MAX_REQUEST_BLOB_SIDECARS: 768
 MIN_EPOCHS_FOR_BLOB_SIDECARS_REQUESTS: 4096
 # `6`
 BLOB_SIDECAR_SUBNET_COUNT: 6
+# `uint64(6)`
+MAX_BLOBS_PER_BLOCK: 6
 
 # DAS
-CUSTODY_REQUIREMENT: 4
-DATA_COLUMN_SIDECAR_SUBNET_COUNT: 128
 NUMBER_OF_COLUMNS: 128
-SAMPLES_PER_SLOT: 8
\ No newline at end of file
+NUMBER_OF_CUSTODY_GROUPS: 128
+DATA_COLUMN_SIDECAR_SUBNET_COUNT: 128
+SAMPLES_PER_SLOT: 8
+CUSTODY_REQUIREMENT: 4
diff --git a/common/filesystem/Cargo.toml b/common/filesystem/Cargo.toml
index fd026bd517..1b5abf03f4 100644
--- a/common/filesystem/Cargo.toml
+++ b/common/filesystem/Cargo.toml
@@ -3,7 +3,6 @@ name = "filesystem"
 version = "0.1.0"
 authors = ["Mark Mackey <mark@sigmaprime.io>"]
 edition = { workspace = true }
-
 # See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
 
 [dependencies]
diff --git a/common/health_metrics/Cargo.toml b/common/health_metrics/Cargo.toml
new file mode 100644
index 0000000000..08591471b2
--- /dev/null
+++ b/common/health_metrics/Cargo.toml
@@ -0,0 +1,12 @@
+[package]
+name = "health_metrics"
+version = "0.1.0"
+edition = { workspace = true }
+
+[dependencies]
+eth2 = { workspace = true }
+metrics = { workspace = true }
+
+[target.'cfg(target_os = "linux")'.dependencies]
+psutil = "3.3.0"
+procfs = "0.15.1"
diff --git a/common/health_metrics/src/lib.rs b/common/health_metrics/src/lib.rs
new file mode 100644
index 0000000000..bab80fb912
--- /dev/null
+++ b/common/health_metrics/src/lib.rs
@@ -0,0 +1,2 @@
+pub mod metrics;
+pub mod observe;
diff --git a/common/warp_utils/src/metrics.rs b/common/health_metrics/src/metrics.rs
similarity index 99%
rename from common/warp_utils/src/metrics.rs
rename to common/health_metrics/src/metrics.rs
index fabcf93650..c216426b7d 100644
--- a/common/warp_utils/src/metrics.rs
+++ b/common/health_metrics/src/metrics.rs
@@ -1,3 +1,4 @@
+use crate::observe::Observe;
 use eth2::lighthouse::{ProcessHealth, SystemHealth};
 use metrics::*;
 use std::sync::LazyLock;
diff --git a/common/health_metrics/src/observe.rs b/common/health_metrics/src/observe.rs
new file mode 100644
index 0000000000..81bb8e6f7e
--- /dev/null
+++ b/common/health_metrics/src/observe.rs
@@ -0,0 +1,127 @@
+use eth2::lighthouse::{Health, ProcessHealth, SystemHealth};
+
+#[cfg(target_os = "linux")]
+use {
+    psutil::cpu::os::linux::CpuTimesExt, psutil::memory::os::linux::VirtualMemoryExt,
+    psutil::process::Process,
+};
+
+pub trait Observe: Sized {
+    fn observe() -> Result<Self, String>;
+}
+
+impl Observe for Health {
+    #[cfg(not(target_os = "linux"))]
+    fn observe() -> Result<Self, String> {
+        Err("Health is only available on Linux".into())
+    }
+
+    #[cfg(target_os = "linux")]
+    fn observe() -> Result<Self, String> {
+        Ok(Self {
+            process: ProcessHealth::observe()?,
+            system: SystemHealth::observe()?,
+        })
+    }
+}
+
+impl Observe for SystemHealth {
+    #[cfg(not(target_os = "linux"))]
+    fn observe() -> Result<Self, String> {
+        Err("Health is only available on Linux".into())
+    }
+
+    #[cfg(target_os = "linux")]
+    fn observe() -> Result<Self, String> {
+        let vm = psutil::memory::virtual_memory()
+            .map_err(|e| format!("Unable to get virtual memory: {:?}", e))?;
+        let loadavg =
+            psutil::host::loadavg().map_err(|e| format!("Unable to get loadavg: {:?}", e))?;
+
+        let cpu =
+            psutil::cpu::cpu_times().map_err(|e| format!("Unable to get cpu times: {:?}", e))?;
+
+        let disk_usage = psutil::disk::disk_usage("/")
+            .map_err(|e| format!("Unable to disk usage info: {:?}", e))?;
+
+        let disk = psutil::disk::DiskIoCountersCollector::default()
+            .disk_io_counters()
+            .map_err(|e| format!("Unable to get disk counters: {:?}", e))?;
+
+        let net = psutil::network::NetIoCountersCollector::default()
+            .net_io_counters()
+            .map_err(|e| format!("Unable to get network io counters: {:?}", e))?;
+
+        let boot_time = psutil::host::boot_time()
+            .map_err(|e| format!("Unable to get system boot time: {:?}", e))?
+            .duration_since(std::time::UNIX_EPOCH)
+            .map_err(|e| format!("Boot time is lower than unix epoch: {}", e))?
+            .as_secs();
+
+        Ok(Self {
+            sys_virt_mem_total: vm.total(),
+            sys_virt_mem_available: vm.available(),
+            sys_virt_mem_used: vm.used(),
+            sys_virt_mem_free: vm.free(),
+            sys_virt_mem_cached: vm.cached(),
+            sys_virt_mem_buffers: vm.buffers(),
+            sys_virt_mem_percent: vm.percent(),
+            sys_loadavg_1: loadavg.one,
+            sys_loadavg_5: loadavg.five,
+            sys_loadavg_15: loadavg.fifteen,
+            cpu_cores: psutil::cpu::cpu_count_physical(),
+            cpu_threads: psutil::cpu::cpu_count(),
+            system_seconds_total: cpu.system().as_secs(),
+            cpu_time_total: cpu.total().as_secs(),
+            user_seconds_total: cpu.user().as_secs(),
+            iowait_seconds_total: cpu.iowait().as_secs(),
+            idle_seconds_total: cpu.idle().as_secs(),
+            disk_node_bytes_total: disk_usage.total(),
+            disk_node_bytes_free: disk_usage.free(),
+            disk_node_reads_total: disk.read_count(),
+            disk_node_writes_total: disk.write_count(),
+            network_node_bytes_total_received: net.bytes_recv(),
+            network_node_bytes_total_transmit: net.bytes_sent(),
+            misc_node_boot_ts_seconds: boot_time,
+            misc_os: std::env::consts::OS.to_string(),
+        })
+    }
+}
+
+impl Observe for ProcessHealth {
+    #[cfg(not(target_os = "linux"))]
+    fn observe() -> Result<Self, String> {
+        Err("Health is only available on Linux".into())
+    }
+
+    #[cfg(target_os = "linux")]
+    fn observe() -> Result<Self, String> {
+        let process =
+            Process::current().map_err(|e| format!("Unable to get current process: {:?}", e))?;
+
+        let process_mem = process
+            .memory_info()
+            .map_err(|e| format!("Unable to get process memory info: {:?}", e))?;
+
+        let me = procfs::process::Process::myself()
+            .map_err(|e| format!("Unable to get process: {:?}", e))?;
+        let stat = me
+            .stat()
+            .map_err(|e| format!("Unable to get stat: {:?}", e))?;
+
+        let process_times = process
+            .cpu_times()
+            .map_err(|e| format!("Unable to get process cpu times : {:?}", e))?;
+
+        Ok(Self {
+            pid: process.pid(),
+            pid_num_threads: stat.num_threads,
+            pid_mem_resident_set_size: process_mem.rss(),
+            pid_mem_virtual_memory_size: process_mem.vms(),
+            pid_mem_shared_memory_size: process_mem.shared(),
+            pid_process_seconds_total: process_times.busy().as_secs()
+                + process_times.children_system().as_secs()
+                + process_times.children_system().as_secs(),
+        })
+    }
+}
diff --git a/common/lighthouse_version/src/lib.rs b/common/lighthouse_version/src/lib.rs
index 0751bdadff..a35b8c42c1 100644
--- a/common/lighthouse_version/src/lib.rs
+++ b/common/lighthouse_version/src/lib.rs
@@ -48,6 +48,22 @@ pub fn version_with_platform() -> String {
     format!("{}/{}-{}", VERSION, Target::arch(), Target::os())
 }
 
+/// Returns semantic versioning information only.
+///
+/// ## Example
+///
+/// `1.5.1`
+pub fn version() -> &'static str {
+    "6.0.1"
+}
+
+/// Returns the name of the current client running.
+///
+/// This will usually be "Lighthouse"
+pub fn client_name() -> &'static str {
+    "Lighthouse"
+}
+
 #[cfg(test)]
 mod test {
     use super::*;
@@ -64,4 +80,14 @@ mod test {
             VERSION
         );
     }
+
+    #[test]
+    fn semantic_version_formatting() {
+        let re = Regex::new(r"^[0-9]+\.[0-9]+\.[0-9]+").unwrap();
+        assert!(
+            re.is_match(version()),
+            "semantic version doesn't match regex: {}",
+            version()
+        );
+    }
 }
diff --git a/common/logging/src/lib.rs b/common/logging/src/lib.rs
index 7fe7f79506..0ddd867c2f 100644
--- a/common/logging/src/lib.rs
+++ b/common/logging/src/lib.rs
@@ -204,7 +204,7 @@ impl TimeLatch {
     pub fn elapsed(&mut self) -> bool {
         let now = Instant::now();
 
-        let is_elapsed = self.0.map_or(false, |elapse_time| now > elapse_time);
+        let is_elapsed = self.0.is_some_and(|elapse_time| now > elapse_time);
 
         if is_elapsed || self.0.is_none() {
             self.0 = Some(now + LOG_DEBOUNCE_INTERVAL);
diff --git a/common/malloc_utils/src/jemalloc.rs b/common/malloc_utils/src/jemalloc.rs
index 0e2e00cb0e..f3a35fc41c 100644
--- a/common/malloc_utils/src/jemalloc.rs
+++ b/common/malloc_utils/src/jemalloc.rs
@@ -9,7 +9,7 @@
 //! B) `_RJEM_MALLOC_CONF` at runtime.
 use metrics::{set_gauge, try_create_int_gauge, IntGauge};
 use std::sync::LazyLock;
-use tikv_jemalloc_ctl::{arenas, epoch, stats, Error};
+use tikv_jemalloc_ctl::{arenas, epoch, stats, Access, AsName, Error};
 
 #[global_allocator]
 static ALLOC: tikv_jemallocator::Jemalloc = tikv_jemallocator::Jemalloc;
@@ -52,3 +52,18 @@ pub fn scrape_jemalloc_metrics_fallible() -> Result<(), Error> {
 
     Ok(())
 }
+
+pub fn page_size() -> Result<usize, Error> {
+    // Full list of keys: https://jemalloc.net/jemalloc.3.html
+    "arenas.page\0".name().read()
+}
+
+#[cfg(test)]
+mod test {
+    use super::*;
+
+    #[test]
+    fn page_size_ok() {
+        assert!(page_size().is_ok());
+    }
+}
diff --git a/common/malloc_utils/src/lib.rs b/common/malloc_utils/src/lib.rs
index 3bb242369f..50d2785a74 100644
--- a/common/malloc_utils/src/lib.rs
+++ b/common/malloc_utils/src/lib.rs
@@ -29,10 +29,10 @@
     not(target_env = "musl"),
     not(feature = "jemalloc")
 ))]
-mod glibc;
+pub mod glibc;
 
 #[cfg(feature = "jemalloc")]
-mod jemalloc;
+pub mod jemalloc;
 
 pub use interface::*;
 
diff --git a/common/monitoring_api/Cargo.toml b/common/monitoring_api/Cargo.toml
index 5008c86e85..cb52cff29a 100644
--- a/common/monitoring_api/Cargo.toml
+++ b/common/monitoring_api/Cargo.toml
@@ -7,6 +7,7 @@ edition = { workspace = true }
 
 [dependencies]
 eth2 = { workspace = true }
+health_metrics = { workspace = true }
 lighthouse_version = { workspace = true }
 metrics = { workspace = true }
 regex = { workspace = true }
diff --git a/common/monitoring_api/src/gather.rs b/common/monitoring_api/src/gather.rs
index 2f6c820f56..43bea35a93 100644
--- a/common/monitoring_api/src/gather.rs
+++ b/common/monitoring_api/src/gather.rs
@@ -1,4 +1,5 @@
 use super::types::{BeaconProcessMetrics, ValidatorProcessMetrics};
+use health_metrics::observe::Observe;
 use metrics::{MetricFamily, MetricType};
 use serde_json::json;
 use std::collections::HashMap;
diff --git a/common/monitoring_api/src/lib.rs b/common/monitoring_api/src/lib.rs
index 9592c50a40..6f919971b0 100644
--- a/common/monitoring_api/src/lib.rs
+++ b/common/monitoring_api/src/lib.rs
@@ -4,6 +4,7 @@ use std::{path::PathBuf, time::Duration};
 
 use eth2::lighthouse::SystemHealth;
 use gather::{gather_beacon_metrics, gather_validator_metrics};
+use health_metrics::observe::Observe;
 use reqwest::{IntoUrl, Response};
 pub use reqwest::{StatusCode, Url};
 use sensitive_url::SensitiveUrl;
diff --git a/common/validator_dir/Cargo.toml b/common/validator_dir/Cargo.toml
index 773431c93c..4c03b7662e 100644
--- a/common/validator_dir/Cargo.toml
+++ b/common/validator_dir/Cargo.toml
@@ -12,7 +12,6 @@ insecure_keys = []
 bls = { workspace = true }
 deposit_contract = { workspace = true }
 derivative = { workspace = true }
-directory = { workspace = true }
 eth2_keystore = { workspace = true }
 filesystem = { workspace = true }
 hex = { workspace = true }
diff --git a/common/validator_dir/src/builder.rs b/common/validator_dir/src/builder.rs
index 3d5d149608..2e971a8b1a 100644
--- a/common/validator_dir/src/builder.rs
+++ b/common/validator_dir/src/builder.rs
@@ -1,7 +1,6 @@
 use crate::{Error as DirError, ValidatorDir};
 use bls::get_withdrawal_credentials;
 use deposit_contract::{encode_eth1_tx_data, Error as DepositError};
-use directory::ensure_dir_exists;
 use eth2_keystore::{Error as KeystoreError, Keystore, KeystoreBuilder, PlainText};
 use filesystem::create_with_600_perms;
 use rand::{distributions::Alphanumeric, Rng};
@@ -42,7 +41,7 @@ pub enum Error {
     #[cfg(feature = "insecure_keys")]
     InsecureKeysError(String),
     MissingPasswordDir,
-    UnableToCreatePasswordDir(String),
+    UnableToCreatePasswordDir(io::Error),
 }
 
 impl From<KeystoreError> for Error {
@@ -163,7 +162,7 @@ impl<'a> Builder<'a> {
         }
 
         if let Some(password_dir) = &self.password_dir {
-            ensure_dir_exists(password_dir).map_err(Error::UnableToCreatePasswordDir)?;
+            create_dir_all(password_dir).map_err(Error::UnableToCreatePasswordDir)?;
         }
 
         // The withdrawal keystore must be initialized in order to store it or create an eth1
diff --git a/common/warp_utils/Cargo.toml b/common/warp_utils/Cargo.toml
index 4a3cde54a9..ec2d23686b 100644
--- a/common/warp_utils/Cargo.toml
+++ b/common/warp_utils/Cargo.toml
@@ -6,7 +6,6 @@ edition = { workspace = true }
 # See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
 
 [dependencies]
-beacon_chain = { workspace = true }
 bytes = { workspace = true }
 eth2 = { workspace = true }
 headers = "0.3.2"
@@ -15,7 +14,6 @@ safe_arith = { workspace = true }
 serde = { workspace = true }
 serde_array_query = "0.1.0"
 serde_json = { workspace = true }
-state_processing = { workspace = true }
 tokio = { workspace = true }
 types = { workspace = true }
 warp = { workspace = true }
diff --git a/common/warp_utils/src/lib.rs b/common/warp_utils/src/lib.rs
index 55ee423fa4..c10adbac0d 100644
--- a/common/warp_utils/src/lib.rs
+++ b/common/warp_utils/src/lib.rs
@@ -3,7 +3,6 @@
 
 pub mod cors;
 pub mod json;
-pub mod metrics;
 pub mod query;
 pub mod reject;
 pub mod task;
diff --git a/common/warp_utils/src/reject.rs b/common/warp_utils/src/reject.rs
index bbd5274a7e..3c7ef5e4fa 100644
--- a/common/warp_utils/src/reject.rs
+++ b/common/warp_utils/src/reject.rs
@@ -2,6 +2,7 @@ use eth2::types::{ErrorMessage, Failure, IndexedErrorMessage};
 use std::convert::Infallible;
 use std::error::Error;
 use std::fmt;
+use std::fmt::Debug;
 use warp::{http::StatusCode, reject::Reject, reply::Response, Reply};
 
 #[derive(Debug)]
@@ -19,15 +20,6 @@ pub fn server_sent_event_error(s: String) -> ServerSentEventError {
     ServerSentEventError(s)
 }
 
-#[derive(Debug)]
-pub struct BeaconChainError(pub beacon_chain::BeaconChainError);
-
-impl Reject for BeaconChainError {}
-
-pub fn beacon_chain_error(e: beacon_chain::BeaconChainError) -> warp::reject::Rejection {
-    warp::reject::custom(BeaconChainError(e))
-}
-
 #[derive(Debug)]
 pub struct BeaconStateError(pub types::BeaconStateError);
 
@@ -47,21 +39,12 @@ pub fn arith_error(e: safe_arith::ArithError) -> warp::reject::Rejection {
 }
 
 #[derive(Debug)]
-pub struct SlotProcessingError(pub state_processing::SlotProcessingError);
+pub struct UnhandledError(pub Box<dyn Debug + Send + Sync + 'static>);
 
-impl Reject for SlotProcessingError {}
+impl Reject for UnhandledError {}
 
-pub fn slot_processing_error(e: state_processing::SlotProcessingError) -> warp::reject::Rejection {
-    warp::reject::custom(SlotProcessingError(e))
-}
-
-#[derive(Debug)]
-pub struct BlockProductionError(pub beacon_chain::BlockProductionError);
-
-impl Reject for BlockProductionError {}
-
-pub fn block_production_error(e: beacon_chain::BlockProductionError) -> warp::reject::Rejection {
-    warp::reject::custom(BlockProductionError(e))
+pub fn unhandled_error<D: Debug + Send + Sync + 'static>(e: D) -> warp::reject::Rejection {
+    warp::reject::custom(UnhandledError(Box::new(e)))
 }
 
 #[derive(Debug)]
@@ -191,16 +174,7 @@ pub async fn handle_rejection(err: warp::Rejection) -> Result<impl warp::Reply,
     } else if let Some(e) = err.find::<warp::reject::InvalidQuery>() {
         code = StatusCode::BAD_REQUEST;
         message = format!("BAD_REQUEST: invalid query: {}", e);
-    } else if let Some(e) = err.find::<crate::reject::BeaconChainError>() {
-        code = StatusCode::INTERNAL_SERVER_ERROR;
-        message = format!("UNHANDLED_ERROR: {:?}", e.0);
-    } else if let Some(e) = err.find::<crate::reject::BeaconStateError>() {
-        code = StatusCode::INTERNAL_SERVER_ERROR;
-        message = format!("UNHANDLED_ERROR: {:?}", e.0);
-    } else if let Some(e) = err.find::<crate::reject::SlotProcessingError>() {
-        code = StatusCode::INTERNAL_SERVER_ERROR;
-        message = format!("UNHANDLED_ERROR: {:?}", e.0);
-    } else if let Some(e) = err.find::<crate::reject::BlockProductionError>() {
+    } else if let Some(e) = err.find::<crate::reject::UnhandledError>() {
         code = StatusCode::INTERNAL_SERVER_ERROR;
         message = format!("UNHANDLED_ERROR: {:?}", e.0);
     } else if let Some(e) = err.find::<crate::reject::CustomNotFound>() {
diff --git a/consensus/fork_choice/src/fork_choice.rs b/consensus/fork_choice/src/fork_choice.rs
index dc6ea98240..fcf6e65460 100644
--- a/consensus/fork_choice/src/fork_choice.rs
+++ b/consensus/fork_choice/src/fork_choice.rs
@@ -762,20 +762,15 @@ where
             if let Some((parent_justified, parent_finalized)) = parent_checkpoints {
                 (parent_justified, parent_finalized)
             } else {
-                let justification_and_finalization_state = match block {
-                    BeaconBlockRef::Electra(_)
-                    | BeaconBlockRef::Deneb(_)
-                    | BeaconBlockRef::Capella(_)
-                    | BeaconBlockRef::Bellatrix(_)
-                    | BeaconBlockRef::Altair(_) => {
+                let justification_and_finalization_state =
+                    if block.fork_name_unchecked().altair_enabled() {
                         // NOTE: Processing justification & finalization requires the progressive
                         // balances cache, but we cannot initialize it here as we only have an
                         // immutable reference. The state *should* have come straight from block
                         // processing, which initialises the cache, but if we add other `on_block`
                         // calls in future it could be worth passing a mutable reference.
                         per_epoch_processing::altair::process_justification_and_finalization(state)?
-                    }
-                    BeaconBlockRef::Base(_) => {
+                    } else {
                         let mut validator_statuses =
                             per_epoch_processing::base::ValidatorStatuses::new(state, spec)
                                 .map_err(Error::ValidatorStatuses)?;
@@ -787,8 +782,7 @@ where
                             &validator_statuses.total_balances,
                             spec,
                         )?
-                    }
-                };
+                    };
 
                 (
                     justification_and_finalization_state.current_justified_checkpoint(),
diff --git a/consensus/fork_choice/tests/tests.rs b/consensus/fork_choice/tests/tests.rs
index ef017159a0..b224cde048 100644
--- a/consensus/fork_choice/tests/tests.rs
+++ b/consensus/fork_choice/tests/tests.rs
@@ -10,6 +10,7 @@ use beacon_chain::{
 use fork_choice::{
     ForkChoiceStore, InvalidAttestation, InvalidBlock, PayloadVerificationStatus, QueuedAttestation,
 };
+use state_processing::state_advance::complete_state_advance;
 use std::fmt;
 use std::sync::Mutex;
 use std::time::Duration;
@@ -53,7 +54,7 @@ impl ForkChoiceTest {
     /// Creates a new tester with a custom chain config.
     pub fn new_with_chain_config(chain_config: ChainConfig) -> Self {
         // Run fork choice tests against the latest fork.
-        let spec = ForkName::latest().make_genesis_spec(ChainSpec::default());
+        let spec = ForkName::latest_stable().make_genesis_spec(ChainSpec::default());
         let harness = BeaconChainHarness::builder(MainnetEthSpec)
             .spec(spec.into())
             .chain_config(chain_config)
@@ -172,6 +173,20 @@ impl ForkChoiceTest {
         let validators = self.harness.get_all_validators();
         loop {
             let slot = self.harness.get_current_slot();
+
+            // Skip slashed proposers, as we expect validators to get slashed in these tests.
+            // Presently `make_block` will panic if the proposer is slashed, so we just avoid
+            // calling it in this case.
+            complete_state_advance(&mut state, None, slot, &self.harness.spec).unwrap();
+            state.build_caches(&self.harness.spec).unwrap();
+            let proposer_index = state
+                .get_beacon_proposer_index(slot, &self.harness.chain.spec)
+                .unwrap();
+            if state.validators().get(proposer_index).unwrap().slashed {
+                self.harness.advance_slot();
+                continue;
+            }
+
             let (block_contents, state_) = self.harness.make_block(state, slot).await;
             state = state_;
             if !predicate(block_contents.0.message(), &state) {
@@ -196,17 +211,20 @@ impl ForkChoiceTest {
     }
 
     /// Apply `count` blocks to the chain (with attestations).
+    ///
+    /// Note that in the case of slashed validators, their proposals will be skipped and the chain
+    /// may be advanced by *more than* `count` slots.
     pub async fn apply_blocks(self, count: usize) -> Self {
-        self.harness.advance_slot();
-        self.harness
-            .extend_chain(
-                count,
-                BlockStrategy::OnCanonicalHead,
-                AttestationStrategy::AllValidators,
-            )
-            .await;
-
-        self
+        // Use `Self::apply_blocks_while` which gracefully handles slashed validators.
+        let mut blocks_applied = 0;
+        self.apply_blocks_while(|_, _| {
+            // Blocks are applied after the predicate is called, so continue applying the block if
+            // less than *or equal* to the count.
+            blocks_applied += 1;
+            blocks_applied <= count
+        })
+        .await
+        .unwrap()
     }
 
     /// Slash a validator from the previous epoch committee.
@@ -244,6 +262,7 @@ impl ForkChoiceTest {
 
     /// Apply `count` blocks to the chain (without attestations).
     pub async fn apply_blocks_without_new_attestations(self, count: usize) -> Self {
+        // This function does not gracefully handle slashed proposers, but may need to in future.
         self.harness.advance_slot();
         self.harness
             .extend_chain(
@@ -1226,14 +1245,6 @@ async fn progressive_balances_cache_attester_slashing() {
         .apply_blocks_while(|_, state| state.finalized_checkpoint().epoch == 0)
         .await
         .unwrap()
-        // Note: This test may fail if the shuffling used changes, right now it re-runs with
-        // deterministic shuffling. A shuffling change my cause the slashed proposer to propose
-        // again in the next epoch, which results in a block processing failure
-        // (`HeaderInvalid::ProposerSlashed`). The harness should be re-worked to successfully skip
-        // the slot in this scenario rather than panic-ing. The same applies to
-        // `progressive_balances_cache_proposer_slashing`.
-        .apply_blocks(2)
-        .await
         .add_previous_epoch_attester_slashing()
         .await
         // expect fork choice to import blocks successfully after a previous epoch attester is
@@ -1244,7 +1255,7 @@ async fn progressive_balances_cache_attester_slashing() {
         // expect fork choice to import another epoch of blocks successfully - the slashed
         // attester's balance should be excluded from the current epoch total balance in
         // `ProgressiveBalancesCache` as well.
-        .apply_blocks(MainnetEthSpec::slots_per_epoch() as usize)
+        .apply_blocks(E::slots_per_epoch() as usize)
         .await;
 }
 
@@ -1257,15 +1268,7 @@ async fn progressive_balances_cache_proposer_slashing() {
         .apply_blocks_while(|_, state| state.finalized_checkpoint().epoch == 0)
         .await
         .unwrap()
-        // Note: This test may fail if the shuffling used changes, right now it re-runs with
-        // deterministic shuffling. A shuffling change may cause the slashed proposer to propose
-        // again in the next epoch, which results in a block processing failure
-        // (`HeaderInvalid::ProposerSlashed`). The harness should be re-worked to successfully skip
-        // the slot in this scenario rather than panic-ing. The same applies to
-        // `progressive_balances_cache_attester_slashing`.
-        .apply_blocks(2)
-        .await
-        .add_previous_epoch_proposer_slashing(MainnetEthSpec::slots_per_epoch())
+        .add_previous_epoch_proposer_slashing(E::slots_per_epoch())
         .await
         // expect fork choice to import blocks successfully after a previous epoch proposer is
         // slashed, i.e. the slashed proposer's balance is correctly excluded from
@@ -1275,6 +1278,6 @@ async fn progressive_balances_cache_proposer_slashing() {
         // expect fork choice to import another epoch of blocks successfully - the slashed
         // proposer's balance should be excluded from the current epoch total balance in
         // `ProgressiveBalancesCache` as well.
-        .apply_blocks(MainnetEthSpec::slots_per_epoch() as usize)
+        .apply_blocks(E::slots_per_epoch() as usize)
         .await;
 }
diff --git a/consensus/merkle_proof/Cargo.toml b/consensus/merkle_proof/Cargo.toml
index c2c6bf270a..2f721d917b 100644
--- a/consensus/merkle_proof/Cargo.toml
+++ b/consensus/merkle_proof/Cargo.toml
@@ -7,8 +7,8 @@ edition = { workspace = true }
 [dependencies]
 alloy-primitives = { workspace = true }
 ethereum_hashing = { workspace = true }
-safe_arith = { workspace = true }
 fixed_bytes = { workspace = true }
+safe_arith = { workspace = true }
 
 [dev-dependencies]
 quickcheck = { workspace = true }
diff --git a/consensus/proto_array/src/proto_array.rs b/consensus/proto_array/src/proto_array.rs
index 9cb415839f..6480a84d8c 100644
--- a/consensus/proto_array/src/proto_array.rs
+++ b/consensus/proto_array/src/proto_array.rs
@@ -473,7 +473,7 @@ impl ProtoArray {
         // 1. The `head_block_root` is a descendant of `latest_valid_ancestor_hash`
         // 2. The `latest_valid_ancestor_hash` is equal to or a descendant of the finalized block.
         let latest_valid_ancestor_is_descendant =
-            latest_valid_ancestor_root.map_or(false, |ancestor_root| {
+            latest_valid_ancestor_root.is_some_and(|ancestor_root| {
                 self.is_descendant(ancestor_root, head_block_root)
                     && self.is_finalized_checkpoint_or_descendant::<E>(ancestor_root)
             });
@@ -510,13 +510,13 @@ impl ProtoArray {
                         // head.
                         if node
                             .best_child
-                            .map_or(false, |i| invalidated_indices.contains(&i))
+                            .is_some_and(|i| invalidated_indices.contains(&i))
                         {
                             node.best_child = None
                         }
                         if node
                             .best_descendant
-                            .map_or(false, |i| invalidated_indices.contains(&i))
+                            .is_some_and(|i| invalidated_indices.contains(&i))
                         {
                             node.best_descendant = None
                         }
@@ -1008,7 +1008,7 @@ impl ProtoArray {
             node.unrealized_finalized_checkpoint,
             node.unrealized_justified_checkpoint,
         ] {
-            if checkpoint.map_or(false, |cp| cp == self.finalized_checkpoint) {
+            if checkpoint.is_some_and(|cp| cp == self.finalized_checkpoint) {
                 return true;
             }
         }
@@ -1046,7 +1046,7 @@ impl ProtoArray {
             .find(|node| {
                 node.execution_status
                     .block_hash()
-                    .map_or(false, |node_block_hash| node_block_hash == *block_hash)
+                    .is_some_and(|node_block_hash| node_block_hash == *block_hash)
             })
             .map(|node| node.root)
     }
diff --git a/consensus/state_processing/src/common/get_attestation_participation.rs b/consensus/state_processing/src/common/get_attestation_participation.rs
index fc09dad1f4..2c6fd3b215 100644
--- a/consensus/state_processing/src/common/get_attestation_participation.rs
+++ b/consensus/state_processing/src/common/get_attestation_participation.rs
@@ -44,22 +44,15 @@ pub fn get_attestation_participation_flag_indices<E: EthSpec>(
     if is_matching_source && inclusion_delay <= E::slots_per_epoch().integer_sqrt() {
         participation_flag_indices.push(TIMELY_SOURCE_FLAG_INDEX);
     }
-    match state {
-        &BeaconState::Base(_)
-        | &BeaconState::Altair(_)
-        | &BeaconState::Bellatrix(_)
-        | &BeaconState::Capella(_) => {
-            if is_matching_target && inclusion_delay <= E::slots_per_epoch() {
-                participation_flag_indices.push(TIMELY_TARGET_FLAG_INDEX);
-            }
-        }
-        &BeaconState::Deneb(_) | &BeaconState::Electra(_) => {
-            if is_matching_target {
-                // [Modified in Deneb:EIP7045]
-                participation_flag_indices.push(TIMELY_TARGET_FLAG_INDEX);
-            }
+    if state.fork_name_unchecked().deneb_enabled() {
+        if is_matching_target {
+            // [Modified in Deneb:EIP7045]
+            participation_flag_indices.push(TIMELY_TARGET_FLAG_INDEX);
         }
+    } else if is_matching_target && inclusion_delay <= E::slots_per_epoch() {
+        participation_flag_indices.push(TIMELY_TARGET_FLAG_INDEX);
     }
+
     if is_matching_head && inclusion_delay == spec.min_attestation_inclusion_delay {
         participation_flag_indices.push(TIMELY_HEAD_FLAG_INDEX);
     }
diff --git a/consensus/state_processing/src/common/slash_validator.rs b/consensus/state_processing/src/common/slash_validator.rs
index 80d857cc00..bd60f16014 100644
--- a/consensus/state_processing/src/common/slash_validator.rs
+++ b/consensus/state_processing/src/common/slash_validator.rs
@@ -55,15 +55,12 @@ pub fn slash_validator<E: EthSpec>(
     let whistleblower_index = opt_whistleblower_index.unwrap_or(proposer_index);
     let whistleblower_reward = validator_effective_balance
         .safe_div(spec.whistleblower_reward_quotient_for_state(state))?;
-    let proposer_reward = match state {
-        BeaconState::Base(_) => whistleblower_reward.safe_div(spec.proposer_reward_quotient)?,
-        BeaconState::Altair(_)
-        | BeaconState::Bellatrix(_)
-        | BeaconState::Capella(_)
-        | BeaconState::Deneb(_)
-        | BeaconState::Electra(_) => whistleblower_reward
+    let proposer_reward = if state.fork_name_unchecked().altair_enabled() {
+        whistleblower_reward
             .safe_mul(PROPOSER_WEIGHT)?
-            .safe_div(WEIGHT_DENOMINATOR)?,
+            .safe_div(WEIGHT_DENOMINATOR)?
+    } else {
+        whistleblower_reward.safe_div(spec.proposer_reward_quotient)?
     };
 
     // Ensure the whistleblower index is in the validator registry.
diff --git a/consensus/state_processing/src/genesis.rs b/consensus/state_processing/src/genesis.rs
index 00697def5d..10723ecc51 100644
--- a/consensus/state_processing/src/genesis.rs
+++ b/consensus/state_processing/src/genesis.rs
@@ -4,7 +4,7 @@ use super::per_block_processing::{
 use crate::common::DepositDataTree;
 use crate::upgrade::electra::upgrade_state_to_electra;
 use crate::upgrade::{
-    upgrade_to_altair, upgrade_to_bellatrix, upgrade_to_capella, upgrade_to_deneb,
+    upgrade_to_altair, upgrade_to_bellatrix, upgrade_to_capella, upgrade_to_deneb, upgrade_to_fulu,
 };
 use safe_arith::{ArithError, SafeArith};
 use std::sync::Arc;
@@ -53,7 +53,7 @@ pub fn initialize_beacon_state_from_eth1<E: EthSpec>(
     // https://github.com/ethereum/eth2.0-specs/pull/2323
     if spec
         .altair_fork_epoch
-        .map_or(false, |fork_epoch| fork_epoch == E::genesis_epoch())
+        .is_some_and(|fork_epoch| fork_epoch == E::genesis_epoch())
     {
         upgrade_to_altair(&mut state, spec)?;
 
@@ -63,7 +63,7 @@ pub fn initialize_beacon_state_from_eth1<E: EthSpec>(
     // Similarly, perform an upgrade to the merge if configured from genesis.
     if spec
         .bellatrix_fork_epoch
-        .map_or(false, |fork_epoch| fork_epoch == E::genesis_epoch())
+        .is_some_and(|fork_epoch| fork_epoch == E::genesis_epoch())
     {
         // this will set state.latest_execution_payload_header = ExecutionPayloadHeaderBellatrix::default()
         upgrade_to_bellatrix(&mut state, spec)?;
@@ -81,7 +81,7 @@ pub fn initialize_beacon_state_from_eth1<E: EthSpec>(
     // Upgrade to capella if configured from genesis
     if spec
         .capella_fork_epoch
-        .map_or(false, |fork_epoch| fork_epoch == E::genesis_epoch())
+        .is_some_and(|fork_epoch| fork_epoch == E::genesis_epoch())
     {
         upgrade_to_capella(&mut state, spec)?;
 
@@ -98,7 +98,7 @@ pub fn initialize_beacon_state_from_eth1<E: EthSpec>(
     // Upgrade to deneb if configured from genesis
     if spec
         .deneb_fork_epoch
-        .map_or(false, |fork_epoch| fork_epoch == E::genesis_epoch())
+        .is_some_and(|fork_epoch| fork_epoch == E::genesis_epoch())
     {
         upgrade_to_deneb(&mut state, spec)?;
 
@@ -115,7 +115,7 @@ pub fn initialize_beacon_state_from_eth1<E: EthSpec>(
     // Upgrade to electra if configured from genesis.
     if spec
         .electra_fork_epoch
-        .map_or(false, |fork_epoch| fork_epoch == E::genesis_epoch())
+        .is_some_and(|fork_epoch| fork_epoch == E::genesis_epoch())
     {
         let post = upgrade_state_to_electra(&mut state, Epoch::new(0), Epoch::new(0), spec)?;
         state = post;
@@ -135,11 +135,27 @@ pub fn initialize_beacon_state_from_eth1<E: EthSpec>(
 
         // Override latest execution payload header.
         // See https://github.com/ethereum/consensus-specs/blob/dev/specs/capella/beacon-chain.md#testing
-        if let Some(ExecutionPayloadHeader::Electra(header)) = execution_payload_header {
+        if let Some(ExecutionPayloadHeader::Electra(ref header)) = execution_payload_header {
             *state.latest_execution_payload_header_electra_mut()? = header.clone();
         }
     }
 
+    // Upgrade to fulu if configured from genesis.
+    if spec
+        .fulu_fork_epoch
+        .is_some_and(|fork_epoch| fork_epoch == E::genesis_epoch())
+    {
+        upgrade_to_fulu(&mut state, spec)?;
+
+        // Remove intermediate Electra fork from `state.fork`.
+        state.fork_mut().previous_version = spec.fulu_fork_version;
+
+        // Override latest execution payload header.
+        if let Some(ExecutionPayloadHeader::Fulu(header)) = execution_payload_header {
+            *state.latest_execution_payload_header_fulu_mut()? = header.clone();
+        }
+    }
+
     // Now that we have our validators, initialize the caches (including the committees)
     state.build_caches(spec)?;
 
@@ -153,7 +169,7 @@ pub fn initialize_beacon_state_from_eth1<E: EthSpec>(
 pub fn is_valid_genesis_state<E: EthSpec>(state: &BeaconState<E>, spec: &ChainSpec) -> bool {
     state
         .get_active_validator_indices(E::genesis_epoch(), spec)
-        .map_or(false, |active_validators| {
+        .is_ok_and(|active_validators| {
             state.genesis_time() >= spec.min_genesis_time
                 && active_validators.len() as u64 >= spec.min_genesis_active_validator_count
         })
diff --git a/consensus/state_processing/src/per_block_processing.rs b/consensus/state_processing/src/per_block_processing.rs
index 436f4934b9..ef4799c245 100644
--- a/consensus/state_processing/src/per_block_processing.rs
+++ b/consensus/state_processing/src/per_block_processing.rs
@@ -1,7 +1,7 @@
 use crate::consensus_context::ConsensusContext;
 use errors::{BlockOperationError, BlockProcessingError, HeaderInvalid};
 use rayon::prelude::*;
-use safe_arith::{ArithError, SafeArith};
+use safe_arith::{ArithError, SafeArith, SafeArithIter};
 use signature_sets::{block_proposal_signature_set, get_pubkey_from_state, randao_signature_set};
 use std::borrow::Cow;
 use tree_hash::TreeHash;
@@ -391,10 +391,12 @@ pub fn partially_verify_execution_payload<E: EthSpec, Payload: AbstractExecPaylo
 
     if let Ok(blob_commitments) = body.blob_kzg_commitments() {
         // Verify commitments are under the limit.
+        let max_blobs_per_block =
+            spec.max_blobs_per_block(block_slot.epoch(E::slots_per_epoch())) as usize;
         block_verify!(
-            blob_commitments.len() <= E::max_blobs_per_block(),
+            blob_commitments.len() <= max_blobs_per_block,
             BlockProcessingError::ExecutionInvalidBlobsLen {
-                max: E::max_blobs_per_block(),
+                max: max_blobs_per_block,
                 actual: blob_commitments.len(),
             }
         );
@@ -442,6 +444,12 @@ pub fn process_execution_payload<E: EthSpec, Payload: AbstractExecPayload<E>>(
                 _ => return Err(BlockProcessingError::IncorrectStateType),
             }
         }
+        ExecutionPayloadHeaderRefMut::Fulu(header_mut) => {
+            match payload.to_execution_payload_header() {
+                ExecutionPayloadHeader::Fulu(header) => *header_mut = header,
+                _ => return Err(BlockProcessingError::IncorrectStateType),
+            }
+        }
     }
 
     Ok(())
@@ -453,15 +461,17 @@ pub fn process_execution_payload<E: EthSpec, Payload: AbstractExecPayload<E>>(
 /// repeatedly write code to treat these errors as false.
 /// https://github.com/ethereum/consensus-specs/blob/dev/specs/bellatrix/beacon-chain.md#is_merge_transition_complete
 pub fn is_merge_transition_complete<E: EthSpec>(state: &BeaconState<E>) -> bool {
-    match state {
+    if state.fork_name_unchecked().capella_enabled() {
+        true
+    } else if state.fork_name_unchecked().bellatrix_enabled() {
         // We must check defaultness against the payload header with 0x0 roots, as that's what's meant
         // by `ExecutionPayloadHeader()` in the spec.
-        BeaconState::Bellatrix(_) => state
+        state
             .latest_execution_payload_header()
             .map(|header| !header.is_default_with_zero_roots())
-            .unwrap_or(false),
-        BeaconState::Electra(_) | BeaconState::Deneb(_) | BeaconState::Capella(_) => true,
-        BeaconState::Base(_) | BeaconState::Altair(_) => false,
+            .unwrap_or(false)
+    } else {
+        false
     }
 }
 /// https://github.com/ethereum/consensus-specs/blob/dev/specs/bellatrix/beacon-chain.md#is_merge_transition_block
@@ -499,7 +509,7 @@ pub fn compute_timestamp_at_slot<E: EthSpec>(
 
 /// Compute the next batch of withdrawals which should be included in a block.
 ///
-/// https://github.com/ethereum/consensus-specs/blob/dev/specs/capella/beacon-chain.md#new-get_expected_withdrawals
+/// https://github.com/ethereum/consensus-specs/blob/dev/specs/electra/beacon-chain.md#new-get_expected_withdrawals
 pub fn get_expected_withdrawals<E: EthSpec>(
     state: &BeaconState<E>,
     spec: &ChainSpec,
@@ -512,18 +522,18 @@ pub fn get_expected_withdrawals<E: EthSpec>(
 
     // [New in Electra:EIP7251]
     // Consume pending partial withdrawals
-    let partial_withdrawals_count =
-        if let Ok(partial_withdrawals) = state.pending_partial_withdrawals() {
-            let mut partial_withdrawals_count = 0;
-            for withdrawal in partial_withdrawals {
+    let processed_partial_withdrawals_count =
+        if let Ok(pending_partial_withdrawals) = state.pending_partial_withdrawals() {
+            let mut processed_partial_withdrawals_count = 0;
+            for withdrawal in pending_partial_withdrawals {
                 if withdrawal.withdrawable_epoch > epoch
                     || withdrawals.len() == spec.max_pending_partials_per_withdrawals_sweep as usize
                 {
                     break;
                 }
 
-                let withdrawal_balance = state.get_balance(withdrawal.index as usize)?;
-                let validator = state.get_validator(withdrawal.index as usize)?;
+                let withdrawal_balance = state.get_balance(withdrawal.validator_index as usize)?;
+                let validator = state.get_validator(withdrawal.validator_index as usize)?;
 
                 let has_sufficient_effective_balance =
                     validator.effective_balance >= spec.min_activation_balance;
@@ -539,17 +549,17 @@ pub fn get_expected_withdrawals<E: EthSpec>(
                     );
                     withdrawals.push(Withdrawal {
                         index: withdrawal_index,
-                        validator_index: withdrawal.index,
+                        validator_index: withdrawal.validator_index,
                         address: validator
                             .get_execution_withdrawal_address(spec)
-                            .ok_or(BeaconStateError::NonExecutionAddresWithdrawalCredential)?,
+                            .ok_or(BeaconStateError::NonExecutionAddressWithdrawalCredential)?,
                         amount: withdrawable_balance,
                     });
                     withdrawal_index.safe_add_assign(1)?;
                 }
-                partial_withdrawals_count.safe_add_assign(1)?;
+                processed_partial_withdrawals_count.safe_add_assign(1)?;
             }
-            Some(partial_withdrawals_count)
+            Some(processed_partial_withdrawals_count)
         } else {
             None
         };
@@ -560,10 +570,20 @@ pub fn get_expected_withdrawals<E: EthSpec>(
     );
     for _ in 0..bound {
         let validator = state.get_validator(validator_index as usize)?;
-        let balance = *state.balances().get(validator_index as usize).ok_or(
-            BeaconStateError::BalancesOutOfBounds(validator_index as usize),
-        )?;
-        if validator.is_fully_withdrawable_at(balance, epoch, spec, fork_name) {
+        let partially_withdrawn_balance = withdrawals
+            .iter()
+            .filter_map(|withdrawal| {
+                (withdrawal.validator_index == validator_index).then_some(withdrawal.amount)
+            })
+            .safe_sum()?;
+        let balance = state
+            .balances()
+            .get(validator_index as usize)
+            .ok_or(BeaconStateError::BalancesOutOfBounds(
+                validator_index as usize,
+            ))?
+            .safe_sub(partially_withdrawn_balance)?;
+        if validator.is_fully_withdrawable_validator(balance, epoch, spec, fork_name) {
             withdrawals.push(Withdrawal {
                 index: withdrawal_index,
                 validator_index,
@@ -580,9 +600,7 @@ pub fn get_expected_withdrawals<E: EthSpec>(
                 address: validator
                     .get_execution_withdrawal_address(spec)
                     .ok_or(BlockProcessingError::WithdrawalCredentialsInvalid)?,
-                amount: balance.safe_sub(
-                    validator.get_max_effective_balance(spec, state.fork_name_unchecked()),
-                )?,
+                amount: balance.safe_sub(validator.get_max_effective_balance(spec, fork_name))?,
             });
             withdrawal_index.safe_add_assign(1)?;
         }
@@ -594,7 +612,7 @@ pub fn get_expected_withdrawals<E: EthSpec>(
             .safe_rem(state.validators().len() as u64)?;
     }
 
-    Ok((withdrawals.into(), partial_withdrawals_count))
+    Ok((withdrawals.into(), processed_partial_withdrawals_count))
 }
 
 /// Apply withdrawals to the state.
@@ -603,66 +621,61 @@ pub fn process_withdrawals<E: EthSpec, Payload: AbstractExecPayload<E>>(
     payload: Payload::Ref<'_>,
     spec: &ChainSpec,
 ) -> Result<(), BlockProcessingError> {
-    match state {
-        BeaconState::Capella(_) | BeaconState::Deneb(_) | BeaconState::Electra(_) => {
-            let (expected_withdrawals, partial_withdrawals_count) =
-                get_expected_withdrawals(state, spec)?;
-            let expected_root = expected_withdrawals.tree_hash_root();
-            let withdrawals_root = payload.withdrawals_root()?;
+    if state.fork_name_unchecked().capella_enabled() {
+        let (expected_withdrawals, processed_partial_withdrawals_count) =
+            get_expected_withdrawals(state, spec)?;
+        let expected_root = expected_withdrawals.tree_hash_root();
+        let withdrawals_root = payload.withdrawals_root()?;
 
-            if expected_root != withdrawals_root {
-                return Err(BlockProcessingError::WithdrawalsRootMismatch {
-                    expected: expected_root,
-                    found: withdrawals_root,
-                });
-            }
+        if expected_root != withdrawals_root {
+            return Err(BlockProcessingError::WithdrawalsRootMismatch {
+                expected: expected_root,
+                found: withdrawals_root,
+            });
+        }
 
-            for withdrawal in expected_withdrawals.iter() {
-                decrease_balance(
-                    state,
-                    withdrawal.validator_index as usize,
-                    withdrawal.amount,
-                )?;
-            }
+        for withdrawal in expected_withdrawals.iter() {
+            decrease_balance(
+                state,
+                withdrawal.validator_index as usize,
+                withdrawal.amount,
+            )?;
+        }
 
-            // Update pending partial withdrawals [New in Electra:EIP7251]
-            if let Some(partial_withdrawals_count) = partial_withdrawals_count {
-                // TODO(electra): Use efficient pop_front after milhouse release https://github.com/sigp/milhouse/pull/38
-                let new_partial_withdrawals = state
-                    .pending_partial_withdrawals()?
-                    .iter_from(partial_withdrawals_count)?
-                    .cloned()
-                    .collect::<Vec<_>>();
-                *state.pending_partial_withdrawals_mut()? = List::new(new_partial_withdrawals)?;
-            }
+        // Update pending partial withdrawals [New in Electra:EIP7251]
+        if let Some(processed_partial_withdrawals_count) = processed_partial_withdrawals_count {
+            state
+                .pending_partial_withdrawals_mut()?
+                .pop_front(processed_partial_withdrawals_count)?;
+        }
 
-            // Update the next withdrawal index if this block contained withdrawals
-            if let Some(latest_withdrawal) = expected_withdrawals.last() {
-                *state.next_withdrawal_index_mut()? = latest_withdrawal.index.safe_add(1)?;
+        // Update the next withdrawal index if this block contained withdrawals
+        if let Some(latest_withdrawal) = expected_withdrawals.last() {
+            *state.next_withdrawal_index_mut()? = latest_withdrawal.index.safe_add(1)?;
 
-                // Update the next validator index to start the next withdrawal sweep
-                if expected_withdrawals.len() == E::max_withdrawals_per_payload() {
-                    // Next sweep starts after the latest withdrawal's validator index
-                    let next_validator_index = latest_withdrawal
-                        .validator_index
-                        .safe_add(1)?
-                        .safe_rem(state.validators().len() as u64)?;
-                    *state.next_withdrawal_validator_index_mut()? = next_validator_index;
-                }
-            }
-
-            // Advance sweep by the max length of the sweep if there was not a full set of withdrawals
-            if expected_withdrawals.len() != E::max_withdrawals_per_payload() {
-                let next_validator_index = state
-                    .next_withdrawal_validator_index()?
-                    .safe_add(spec.max_validators_per_withdrawals_sweep)?
+            // Update the next validator index to start the next withdrawal sweep
+            if expected_withdrawals.len() == E::max_withdrawals_per_payload() {
+                // Next sweep starts after the latest withdrawal's validator index
+                let next_validator_index = latest_withdrawal
+                    .validator_index
+                    .safe_add(1)?
                     .safe_rem(state.validators().len() as u64)?;
                 *state.next_withdrawal_validator_index_mut()? = next_validator_index;
             }
-
-            Ok(())
         }
+
+        // Advance sweep by the max length of the sweep if there was not a full set of withdrawals
+        if expected_withdrawals.len() != E::max_withdrawals_per_payload() {
+            let next_validator_index = state
+                .next_withdrawal_validator_index()?
+                .safe_add(spec.max_validators_per_withdrawals_sweep)?
+                .safe_rem(state.validators().len() as u64)?;
+            *state.next_withdrawal_validator_index_mut()? = next_validator_index;
+        }
+
+        Ok(())
+    } else {
         // these shouldn't even be encountered but they're here for completeness
-        BeaconState::Base(_) | BeaconState::Altair(_) | BeaconState::Bellatrix(_) => Ok(()),
+        Ok(())
     }
 }
diff --git a/consensus/state_processing/src/per_block_processing/altair/sync_committee.rs b/consensus/state_processing/src/per_block_processing/altair/sync_committee.rs
index 210db4c9c1..08cfd9cba8 100644
--- a/consensus/state_processing/src/per_block_processing/altair/sync_committee.rs
+++ b/consensus/state_processing/src/per_block_processing/altair/sync_committee.rs
@@ -38,7 +38,7 @@ pub fn process_sync_aggregate<E: EthSpec>(
         )?;
 
         // If signature set is `None` then the signature is valid (infinity).
-        if signature_set.map_or(false, |signature| !signature.verify()) {
+        if signature_set.is_some_and(|signature| !signature.verify()) {
             return Err(SyncAggregateInvalid::SignatureInvalid.into());
         }
     }
diff --git a/consensus/state_processing/src/per_block_processing/process_operations.rs b/consensus/state_processing/src/per_block_processing/process_operations.rs
index 22d8592364..82dd616724 100644
--- a/consensus/state_processing/src/per_block_processing/process_operations.rs
+++ b/consensus/state_processing/src/per_block_processing/process_operations.rs
@@ -284,29 +284,22 @@ pub fn process_attestations<E: EthSpec, Payload: AbstractExecPayload<E>>(
     ctxt: &mut ConsensusContext<E>,
     spec: &ChainSpec,
 ) -> Result<(), BlockProcessingError> {
-    match block_body {
-        BeaconBlockBodyRef::Base(_) => {
-            base::process_attestations(
-                state,
-                block_body.attestations(),
-                verify_signatures,
-                ctxt,
-                spec,
-            )?;
-        }
-        BeaconBlockBodyRef::Altair(_)
-        | BeaconBlockBodyRef::Bellatrix(_)
-        | BeaconBlockBodyRef::Capella(_)
-        | BeaconBlockBodyRef::Deneb(_)
-        | BeaconBlockBodyRef::Electra(_) => {
-            altair_deneb::process_attestations(
-                state,
-                block_body.attestations(),
-                verify_signatures,
-                ctxt,
-                spec,
-            )?;
-        }
+    if state.fork_name_unchecked().altair_enabled() {
+        altair_deneb::process_attestations(
+            state,
+            block_body.attestations(),
+            verify_signatures,
+            ctxt,
+            spec,
+        )?;
+    } else {
+        base::process_attestations(
+            state,
+            block_body.attestations(),
+            verify_signatures,
+            ctxt,
+            spec,
+        )?;
     }
     Ok(())
 }
@@ -514,11 +507,11 @@ pub fn process_withdrawal_requests<E: EthSpec>(
         }
 
         // Verify pubkey exists
-        let Some(index) = state.pubkey_cache().get(&request.validator_pubkey) else {
+        let Some(validator_index) = state.pubkey_cache().get(&request.validator_pubkey) else {
             continue;
         };
 
-        let validator = state.get_validator(index)?;
+        let validator = state.get_validator(validator_index)?;
         // Verify withdrawal credentials
         let has_correct_credential = validator.has_execution_withdrawal_credential(spec);
         let is_correct_source_address = validator
@@ -549,16 +542,16 @@ pub fn process_withdrawal_requests<E: EthSpec>(
             continue;
         }
 
-        let pending_balance_to_withdraw = state.get_pending_balance_to_withdraw(index)?;
+        let pending_balance_to_withdraw = state.get_pending_balance_to_withdraw(validator_index)?;
         if is_full_exit_request {
             // Only exit validator if it has no pending withdrawals in the queue
             if pending_balance_to_withdraw == 0 {
-                initiate_validator_exit(state, index, spec)?
+                initiate_validator_exit(state, validator_index, spec)?
             }
             continue;
         }
 
-        let balance = state.get_balance(index)?;
+        let balance = state.get_balance(validator_index)?;
         let has_sufficient_effective_balance =
             validator.effective_balance >= spec.min_activation_balance;
         let has_excess_balance = balance
@@ -583,7 +576,7 @@ pub fn process_withdrawal_requests<E: EthSpec>(
             state
                 .pending_partial_withdrawals_mut()?
                 .push(PendingPartialWithdrawal {
-                    index: index as u64,
+                    validator_index: validator_index as u64,
                     amount: to_withdraw,
                     withdrawable_epoch,
                 })?;
@@ -746,8 +739,8 @@ pub fn process_consolidation_request<E: EthSpec>(
     }
 
     let target_validator = state.get_validator(target_index)?;
-    // Verify the target has execution withdrawal credentials
-    if !target_validator.has_execution_withdrawal_credential(spec) {
+    // Verify the target has compounding withdrawal credentials
+    if !target_validator.has_compounding_withdrawal_credential(spec) {
         return Ok(());
     }
 
@@ -764,6 +757,18 @@ pub fn process_consolidation_request<E: EthSpec>(
     {
         return Ok(());
     }
+    // Verify the source has been active long enough
+    if current_epoch
+        < source_validator
+            .activation_epoch
+            .safe_add(spec.shard_committee_period)?
+    {
+        return Ok(());
+    }
+    // Verify the source has no pending withdrawals in the queue
+    if state.get_pending_balance_to_withdraw(source_index)? > 0 {
+        return Ok(());
+    }
 
     // Initiate source validator exit and append pending consolidation
     let source_exit_epoch = state
@@ -779,10 +784,5 @@ pub fn process_consolidation_request<E: EthSpec>(
             target_index: target_index as u64,
         })?;
 
-    let target_validator = state.get_validator(target_index)?;
-    // Churn any target excess active balance of target and raise its max
-    if target_validator.has_eth1_withdrawal_credential(spec) {
-        state.switch_to_compounding_validator(target_index, spec)?;
-    }
     Ok(())
 }
diff --git a/consensus/state_processing/src/per_block_processing/signature_sets.rs b/consensus/state_processing/src/per_block_processing/signature_sets.rs
index 2e00ee0341..39f438f97f 100644
--- a/consensus/state_processing/src/per_block_processing/signature_sets.rs
+++ b/consensus/state_processing/src/per_block_processing/signature_sets.rs
@@ -387,22 +387,20 @@ where
     let exit = &signed_exit.message;
     let proposer_index = exit.validator_index as usize;
 
-    let domain = match state {
-        BeaconState::Base(_)
-        | BeaconState::Altair(_)
-        | BeaconState::Bellatrix(_)
-        | BeaconState::Capella(_) => spec.get_domain(
+    let domain = if state.fork_name_unchecked().deneb_enabled() {
+        // EIP-7044
+        spec.compute_domain(
+            Domain::VoluntaryExit,
+            spec.capella_fork_version,
+            state.genesis_validators_root(),
+        )
+    } else {
+        spec.get_domain(
             exit.epoch,
             Domain::VoluntaryExit,
             &state.fork(),
             state.genesis_validators_root(),
-        ),
-        // EIP-7044
-        BeaconState::Deneb(_) | BeaconState::Electra(_) => spec.compute_domain(
-            Domain::VoluntaryExit,
-            spec.capella_fork_version,
-            state.genesis_validators_root(),
-        ),
+        )
     };
 
     let message = exit.signing_root(domain);
diff --git a/consensus/state_processing/src/per_block_processing/verify_attestation.rs b/consensus/state_processing/src/per_block_processing/verify_attestation.rs
index 6bfb51d475..0b399bea6c 100644
--- a/consensus/state_processing/src/per_block_processing/verify_attestation.rs
+++ b/consensus/state_processing/src/per_block_processing/verify_attestation.rs
@@ -32,21 +32,16 @@ pub fn verify_attestation_for_block_inclusion<'ctxt, E: EthSpec>(
             attestation: data.slot,
         }
     );
-    match state {
-        BeaconState::Base(_)
-        | BeaconState::Altair(_)
-        | BeaconState::Bellatrix(_)
-        | BeaconState::Capella(_) => {
-            verify!(
-                state.slot() <= data.slot.safe_add(E::slots_per_epoch())?,
-                Invalid::IncludedTooLate {
-                    state: state.slot(),
-                    attestation: data.slot,
-                }
-            );
-        }
+    if state.fork_name_unchecked().deneb_enabled() {
         // [Modified in Deneb:EIP7045]
-        BeaconState::Deneb(_) | BeaconState::Electra(_) => {}
+    } else {
+        verify!(
+            state.slot() <= data.slot.safe_add(E::slots_per_epoch())?,
+            Invalid::IncludedTooLate {
+                state: state.slot(),
+                attestation: data.slot,
+            }
+        );
     }
 
     verify_attestation_for_state(state, attestation, ctxt, verify_signatures, spec)
diff --git a/consensus/state_processing/src/per_epoch_processing.rs b/consensus/state_processing/src/per_epoch_processing.rs
index 55e8853f3f..41c30c4931 100644
--- a/consensus/state_processing/src/per_epoch_processing.rs
+++ b/consensus/state_processing/src/per_epoch_processing.rs
@@ -41,13 +41,10 @@ pub fn process_epoch<E: EthSpec>(
         .fork_name(spec)
         .map_err(Error::InconsistentStateFork)?;
 
-    match state {
-        BeaconState::Base(_) => base::process_epoch(state, spec),
-        BeaconState::Altair(_)
-        | BeaconState::Bellatrix(_)
-        | BeaconState::Capella(_)
-        | BeaconState::Deneb(_)
-        | BeaconState::Electra(_) => altair::process_epoch(state, spec),
+    if state.fork_name_unchecked().altair_enabled() {
+        altair::process_epoch(state, spec)
+    } else {
+        base::process_epoch(state, spec)
     }
 }
 
diff --git a/consensus/state_processing/src/per_epoch_processing/epoch_processing_summary.rs b/consensus/state_processing/src/per_epoch_processing/epoch_processing_summary.rs
index 952ab3f649..5508b80807 100644
--- a/consensus/state_processing/src/per_epoch_processing/epoch_processing_summary.rs
+++ b/consensus/state_processing/src/per_epoch_processing/epoch_processing_summary.rs
@@ -151,7 +151,7 @@ impl<E: EthSpec> EpochProcessingSummary<E> {
         match self {
             EpochProcessingSummary::Base { statuses, .. } => statuses
                 .get(val_index)
-                .map_or(false, |s| s.is_active_in_current_epoch && !s.is_slashed),
+                .is_some_and(|s| s.is_active_in_current_epoch && !s.is_slashed),
             EpochProcessingSummary::Altair { participation, .. } => {
                 participation.is_active_and_unslashed(val_index, participation.current_epoch)
             }
@@ -176,7 +176,7 @@ impl<E: EthSpec> EpochProcessingSummary<E> {
         match self {
             EpochProcessingSummary::Base { statuses, .. } => Ok(statuses
                 .get(val_index)
-                .map_or(false, |s| s.is_current_epoch_target_attester)),
+                .is_some_and(|s| s.is_current_epoch_target_attester)),
             EpochProcessingSummary::Altair { participation, .. } => participation
                 .is_current_epoch_unslashed_participating_index(
                     val_index,
@@ -247,7 +247,7 @@ impl<E: EthSpec> EpochProcessingSummary<E> {
         match self {
             EpochProcessingSummary::Base { statuses, .. } => statuses
                 .get(val_index)
-                .map_or(false, |s| s.is_active_in_previous_epoch && !s.is_slashed),
+                .is_some_and(|s| s.is_active_in_previous_epoch && !s.is_slashed),
             EpochProcessingSummary::Altair { participation, .. } => {
                 participation.is_active_and_unslashed(val_index, participation.previous_epoch)
             }
@@ -267,7 +267,7 @@ impl<E: EthSpec> EpochProcessingSummary<E> {
         match self {
             EpochProcessingSummary::Base { statuses, .. } => Ok(statuses
                 .get(val_index)
-                .map_or(false, |s| s.is_previous_epoch_target_attester)),
+                .is_some_and(|s| s.is_previous_epoch_target_attester)),
             EpochProcessingSummary::Altair { participation, .. } => participation
                 .is_previous_epoch_unslashed_participating_index(
                     val_index,
@@ -294,7 +294,7 @@ impl<E: EthSpec> EpochProcessingSummary<E> {
         match self {
             EpochProcessingSummary::Base { statuses, .. } => Ok(statuses
                 .get(val_index)
-                .map_or(false, |s| s.is_previous_epoch_head_attester)),
+                .is_some_and(|s| s.is_previous_epoch_head_attester)),
             EpochProcessingSummary::Altair { participation, .. } => participation
                 .is_previous_epoch_unslashed_participating_index(val_index, TIMELY_HEAD_FLAG_INDEX),
         }
@@ -318,7 +318,7 @@ impl<E: EthSpec> EpochProcessingSummary<E> {
         match self {
             EpochProcessingSummary::Base { statuses, .. } => Ok(statuses
                 .get(val_index)
-                .map_or(false, |s| s.is_previous_epoch_attester)),
+                .is_some_and(|s| s.is_previous_epoch_attester)),
             EpochProcessingSummary::Altair { participation, .. } => participation
                 .is_previous_epoch_unslashed_participating_index(
                     val_index,
diff --git a/consensus/state_processing/src/per_epoch_processing/single_pass.rs b/consensus/state_processing/src/per_epoch_processing/single_pass.rs
index 904e68e368..5c31669a60 100644
--- a/consensus/state_processing/src/per_epoch_processing/single_pass.rs
+++ b/consensus/state_processing/src/per_epoch_processing/single_pass.rs
@@ -1057,14 +1057,12 @@ fn process_pending_consolidations<E: EthSpec>(
         }
 
         // Calculate the consolidated balance
-        let max_effective_balance =
-            source_validator.get_max_effective_balance(spec, state_ctxt.fork_name);
         let source_effective_balance = std::cmp::min(
             *state
                 .balances()
                 .get(source_index)
                 .ok_or(BeaconStateError::UnknownValidator(source_index))?,
-            max_effective_balance,
+            source_validator.effective_balance,
         );
 
         // Move active balance to target. Excess balance is withdrawable.
@@ -1077,13 +1075,9 @@ fn process_pending_consolidations<E: EthSpec>(
         next_pending_consolidation.safe_add_assign(1)?;
     }
 
-    let new_pending_consolidations = List::try_from_iter(
-        state
-            .pending_consolidations()?
-            .iter_from(next_pending_consolidation)?
-            .cloned(),
-    )?;
-    *state.pending_consolidations_mut()? = new_pending_consolidations;
+    state
+        .pending_consolidations_mut()?
+        .pop_front(next_pending_consolidation)?;
 
     // the spec tests require we don't perform effective balance updates when testing pending_consolidations
     if !perform_effective_balance_updates {
diff --git a/consensus/state_processing/src/per_slot_processing.rs b/consensus/state_processing/src/per_slot_processing.rs
index 6554423199..af1cce602c 100644
--- a/consensus/state_processing/src/per_slot_processing.rs
+++ b/consensus/state_processing/src/per_slot_processing.rs
@@ -1,6 +1,6 @@
 use crate::upgrade::{
     upgrade_to_altair, upgrade_to_bellatrix, upgrade_to_capella, upgrade_to_deneb,
-    upgrade_to_electra,
+    upgrade_to_electra, upgrade_to_fulu,
 };
 use crate::{per_epoch_processing::EpochProcessingSummary, *};
 use safe_arith::{ArithError, SafeArith};
@@ -71,6 +71,11 @@ pub fn per_slot_processing<E: EthSpec>(
             upgrade_to_electra(state, spec)?;
         }
 
+        // Fulu.
+        if spec.fulu_fork_epoch == Some(state.current_epoch()) {
+            upgrade_to_fulu(state, spec)?;
+        }
+
         // Additionally build all caches so that all valid states that are advanced always have
         // committee caches built, and we don't have to worry about initialising them at higher
         // layers.
diff --git a/consensus/state_processing/src/upgrade.rs b/consensus/state_processing/src/upgrade.rs
index 93cafa73d0..88bc87849f 100644
--- a/consensus/state_processing/src/upgrade.rs
+++ b/consensus/state_processing/src/upgrade.rs
@@ -3,9 +3,11 @@ pub mod bellatrix;
 pub mod capella;
 pub mod deneb;
 pub mod electra;
+pub mod fulu;
 
 pub use altair::upgrade_to_altair;
 pub use bellatrix::upgrade_to_bellatrix;
 pub use capella::upgrade_to_capella;
 pub use deneb::upgrade_to_deneb;
 pub use electra::upgrade_to_electra;
+pub use fulu::upgrade_to_fulu;
diff --git a/consensus/state_processing/src/upgrade/electra.rs b/consensus/state_processing/src/upgrade/electra.rs
index 1e64ef2897..258b28a45b 100644
--- a/consensus/state_processing/src/upgrade/electra.rs
+++ b/consensus/state_processing/src/upgrade/electra.rs
@@ -14,13 +14,15 @@ pub fn upgrade_to_electra<E: EthSpec>(
 ) -> Result<(), Error> {
     let epoch = pre_state.current_epoch();
 
+    let activation_exit_epoch = spec.compute_activation_exit_epoch(epoch)?;
     let earliest_exit_epoch = pre_state
         .validators()
         .iter()
         .filter(|v| v.exit_epoch != spec.far_future_epoch)
         .map(|v| v.exit_epoch)
         .max()
-        .unwrap_or(epoch)
+        .unwrap_or(activation_exit_epoch)
+        .max(activation_exit_epoch)
         .safe_add(1)?;
 
     // The total active balance cache must be built before the consolidation churn limit
@@ -45,10 +47,11 @@ pub fn upgrade_to_electra<E: EthSpec>(
         .enumerate()
         .filter(|(_, validator)| validator.activation_epoch == spec.far_future_epoch)
         .sorted_by_key(|(index, validator)| (validator.activation_eligibility_epoch, *index))
+        .map(|(index, _)| index)
         .collect::<Vec<_>>();
 
     // Process validators to queue entire balance and reset them
-    for (index, _) in pre_activation {
+    for index in pre_activation {
         let balance = post
             .balances_mut()
             .get_mut(index)
diff --git a/consensus/state_processing/src/upgrade/fulu.rs b/consensus/state_processing/src/upgrade/fulu.rs
new file mode 100644
index 0000000000..6e0cd3fa9d
--- /dev/null
+++ b/consensus/state_processing/src/upgrade/fulu.rs
@@ -0,0 +1,94 @@
+use std::mem;
+use types::{BeaconState, BeaconStateError as Error, BeaconStateFulu, ChainSpec, EthSpec, Fork};
+
+/// Transform a `Electra` state into an `Fulu` state.
+pub fn upgrade_to_fulu<E: EthSpec>(
+    pre_state: &mut BeaconState<E>,
+    spec: &ChainSpec,
+) -> Result<(), Error> {
+    let _epoch = pre_state.current_epoch();
+
+    let post = upgrade_state_to_fulu(pre_state, spec)?;
+
+    *pre_state = post;
+
+    Ok(())
+}
+
+pub fn upgrade_state_to_fulu<E: EthSpec>(
+    pre_state: &mut BeaconState<E>,
+    spec: &ChainSpec,
+) -> Result<BeaconState<E>, Error> {
+    let epoch = pre_state.current_epoch();
+    let pre = pre_state.as_electra_mut()?;
+    // Where possible, use something like `mem::take` to move fields from behind the &mut
+    // reference. For other fields that don't have a good default value, use `clone`.
+    //
+    // Fixed size vectors get cloned because replacing them would require the same size
+    // allocation as cloning.
+    let post = BeaconState::Fulu(BeaconStateFulu {
+        // Versioning
+        genesis_time: pre.genesis_time,
+        genesis_validators_root: pre.genesis_validators_root,
+        slot: pre.slot,
+        fork: Fork {
+            previous_version: pre.fork.current_version,
+            current_version: spec.fulu_fork_version,
+            epoch,
+        },
+        // History
+        latest_block_header: pre.latest_block_header.clone(),
+        block_roots: pre.block_roots.clone(),
+        state_roots: pre.state_roots.clone(),
+        historical_roots: mem::take(&mut pre.historical_roots),
+        // Eth1
+        eth1_data: pre.eth1_data.clone(),
+        eth1_data_votes: mem::take(&mut pre.eth1_data_votes),
+        eth1_deposit_index: pre.eth1_deposit_index,
+        // Registry
+        validators: mem::take(&mut pre.validators),
+        balances: mem::take(&mut pre.balances),
+        // Randomness
+        randao_mixes: pre.randao_mixes.clone(),
+        // Slashings
+        slashings: pre.slashings.clone(),
+        // `Participation
+        previous_epoch_participation: mem::take(&mut pre.previous_epoch_participation),
+        current_epoch_participation: mem::take(&mut pre.current_epoch_participation),
+        // Finality
+        justification_bits: pre.justification_bits.clone(),
+        previous_justified_checkpoint: pre.previous_justified_checkpoint,
+        current_justified_checkpoint: pre.current_justified_checkpoint,
+        finalized_checkpoint: pre.finalized_checkpoint,
+        // Inactivity
+        inactivity_scores: mem::take(&mut pre.inactivity_scores),
+        // Sync committees
+        current_sync_committee: pre.current_sync_committee.clone(),
+        next_sync_committee: pre.next_sync_committee.clone(),
+        // Execution
+        latest_execution_payload_header: pre.latest_execution_payload_header.upgrade_to_fulu(),
+        // Capella
+        next_withdrawal_index: pre.next_withdrawal_index,
+        next_withdrawal_validator_index: pre.next_withdrawal_validator_index,
+        historical_summaries: pre.historical_summaries.clone(),
+        // Electra
+        deposit_requests_start_index: pre.deposit_requests_start_index,
+        deposit_balance_to_consume: pre.deposit_balance_to_consume,
+        exit_balance_to_consume: pre.exit_balance_to_consume,
+        earliest_exit_epoch: pre.earliest_exit_epoch,
+        consolidation_balance_to_consume: pre.consolidation_balance_to_consume,
+        earliest_consolidation_epoch: pre.earliest_consolidation_epoch,
+        pending_deposits: pre.pending_deposits.clone(),
+        pending_partial_withdrawals: pre.pending_partial_withdrawals.clone(),
+        pending_consolidations: pre.pending_consolidations.clone(),
+        // Caches
+        total_active_balance: pre.total_active_balance,
+        progressive_balances_cache: mem::take(&mut pre.progressive_balances_cache),
+        committee_caches: mem::take(&mut pre.committee_caches),
+        pubkey_cache: mem::take(&mut pre.pubkey_cache),
+        exit_cache: mem::take(&mut pre.exit_cache),
+        slashings_cache: mem::take(&mut pre.slashings_cache),
+        epoch_cache: mem::take(&mut pre.epoch_cache),
+    });
+    Ok(post)
+}
diff --git a/consensus/types/Cargo.toml b/consensus/types/Cargo.toml
index 21a15fc517..79beb81282 100644
--- a/consensus/types/Cargo.toml
+++ b/consensus/types/Cargo.toml
@@ -10,56 +10,56 @@ harness = false
 
 [dependencies]
 alloy-primitives = { workspace = true }
-merkle_proof = { workspace = true }
-bls = { workspace = true, features = ["arbitrary"] }
-kzg = { workspace = true }
-compare_fields = { workspace = true }
-compare_fields_derive = { workspace = true }
-eth2_interop_keypairs = { path = "../../common/eth2_interop_keypairs" }
-ethereum_hashing = { workspace = true }
-hex = { workspace = true }
-int_to_bytes = { workspace = true }
-log = { workspace = true }
-rayon = { workspace = true }
-rand = { workspace = true }
-safe_arith = { workspace = true }
-serde = { workspace = true, features = ["rc"] }
-slog = { workspace = true }
-ethereum_ssz = { workspace = true, features = ["arbitrary"] }
-ethereum_ssz_derive = { workspace = true }
-ssz_types = { workspace = true, features = ["arbitrary"] }
-swap_or_not_shuffle = { workspace = true, features = ["arbitrary"] }
-test_random_derive = { path = "../../common/test_random_derive" }
-tree_hash = { workspace = true }
-tree_hash_derive = { workspace = true }
-rand_xorshift = "0.3.0"
-serde_yaml = { workspace = true }
-tempfile = { workspace = true }
-derivative = { workspace = true }
-rusqlite = { workspace = true }
+alloy-rlp = { version = "0.3.4", features = ["derive"] }
 # The arbitrary dependency is enabled by default since Capella to avoid complexity introduced by
 # `AbstractExecPayload`
 arbitrary = { workspace = true, features = ["derive"] }
+bls = { workspace = true, features = ["arbitrary"] }
+compare_fields = { workspace = true }
+compare_fields_derive = { workspace = true }
+derivative = { workspace = true }
+eth2_interop_keypairs = { path = "../../common/eth2_interop_keypairs" }
+ethereum_hashing = { workspace = true }
 ethereum_serde_utils = { workspace = true }
-regex = { workspace = true }
-parking_lot = { workspace = true }
-itertools = { workspace = true }
-superstruct = { workspace = true }
-metastruct = "0.1.0"
-serde_json = { workspace = true }
-smallvec = { workspace = true }
-maplit = { workspace = true }
-alloy-rlp = { version = "0.3.4", features = ["derive"] }
-milhouse = { workspace = true }
-rpds = { workspace = true }
+ethereum_ssz = { workspace = true, features = ["arbitrary"] }
+ethereum_ssz_derive = { workspace = true }
 fixed_bytes = { workspace = true }
+hex = { workspace = true }
+int_to_bytes = { workspace = true }
+itertools = { workspace = true }
+kzg = { workspace = true }
+log = { workspace = true }
+maplit = { workspace = true }
+merkle_proof = { workspace = true }
+metastruct = "0.1.0"
+milhouse = { workspace = true }
+parking_lot = { workspace = true }
+rand = { workspace = true }
+rand_xorshift = "0.3.0"
+rayon = { workspace = true }
+regex = { workspace = true }
+rpds = { workspace = true }
+rusqlite = { workspace = true }
+safe_arith = { workspace = true }
+serde = { workspace = true, features = ["rc"] }
+serde_json = { workspace = true }
+serde_yaml = { workspace = true }
+slog = { workspace = true }
+smallvec = { workspace = true }
+ssz_types = { workspace = true, features = ["arbitrary"] }
+superstruct = { workspace = true }
+swap_or_not_shuffle = { workspace = true, features = ["arbitrary"] }
+tempfile = { workspace = true }
+test_random_derive = { path = "../../common/test_random_derive" }
+tree_hash = { workspace = true }
+tree_hash_derive = { workspace = true }
 
 [dev-dependencies]
-criterion = { workspace = true }
 beacon_chain = { workspace = true }
+criterion = { workspace = true }
+paste = { workspace = true }
 state_processing = { workspace = true }
 tokio = { workspace = true }
-paste = { workspace = true }
 
 [features]
 default = ["sqlite", "legacy-arith"]
diff --git a/consensus/types/presets/gnosis/deneb.yaml b/consensus/types/presets/gnosis/deneb.yaml
index d2d7d0abed..d25c4d3d38 100644
--- a/consensus/types/presets/gnosis/deneb.yaml
+++ b/consensus/types/presets/gnosis/deneb.yaml
@@ -1,6 +1,4 @@
 # Gnosis preset - Deneb
-# NOTE: The below are PLACEHOLDER values from Mainnet.
-# Gnosis preset for the Deneb fork TBD: https://github.com/gnosischain/configs/tree/main/presets/gnosis
 
 # Misc
 # ---------------------------------------------------------------
@@ -8,7 +6,5 @@
 FIELD_ELEMENTS_PER_BLOB: 4096
 # `uint64(2**12)` (= 4096)
 MAX_BLOB_COMMITMENTS_PER_BLOCK: 4096
-# `uint64(6)`
-MAX_BLOBS_PER_BLOCK: 6
 # `floorlog2(BLOB_KZG_COMMITMENTS_GINDEX) + 1 + ceillog2(MAX_BLOB_COMMITMENTS_PER_BLOCK)` = 4 + 1 + 12 = 17
 KZG_COMMITMENT_INCLUSION_PROOF_DEPTH: 17
diff --git a/consensus/types/presets/gnosis/electra.yaml b/consensus/types/presets/gnosis/electra.yaml
index 660ed9b64c..42afbb233e 100644
--- a/consensus/types/presets/gnosis/electra.yaml
+++ b/consensus/types/presets/gnosis/electra.yaml
@@ -10,7 +10,7 @@ MAX_EFFECTIVE_BALANCE_ELECTRA: 2048000000000
 # State list lengths
 # ---------------------------------------------------------------
 # `uint64(2**27)` (= 134,217,728)
-PENDING_BALANCE_DEPOSITS_LIMIT: 134217728
+PENDING_DEPOSITS_LIMIT: 134217728
 # `uint64(2**27)` (= 134,217,728)
 PENDING_PARTIAL_WITHDRAWALS_LIMIT: 134217728
 # `uint64(2**18)` (= 262,144)
@@ -29,12 +29,12 @@ WHISTLEBLOWER_REWARD_QUOTIENT_ELECTRA: 4096
 MAX_ATTESTER_SLASHINGS_ELECTRA: 1
 # `uint64(2**3)` (= 8)
 MAX_ATTESTATIONS_ELECTRA: 8
-# `uint64(2**0)` (= 1)
-MAX_CONSOLIDATION_REQUESTS_PER_PAYLOAD: 1
+# `uint64(2**1)` (= 2)
+MAX_CONSOLIDATION_REQUESTS_PER_PAYLOAD: 2
 
 # Execution
 # ---------------------------------------------------------------
-# 2**13 (= 8192) receipts
+# 2**13 (= 8192) deposit requests
 MAX_DEPOSIT_REQUESTS_PER_PAYLOAD: 8192
 # 2**4 (= 16) withdrawal requests
 MAX_WITHDRAWAL_REQUESTS_PER_PAYLOAD: 16
@@ -43,3 +43,8 @@ MAX_WITHDRAWAL_REQUESTS_PER_PAYLOAD: 16
 # ---------------------------------------------------------------
 # 2**3 ( = 8) pending withdrawals
 MAX_PENDING_PARTIALS_PER_WITHDRAWALS_SWEEP: 8
+
+# Pending deposits processing
+# ---------------------------------------------------------------
+# 2**4 ( = 4) pending deposits
+MAX_PENDING_DEPOSITS_PER_EPOCH: 16
diff --git a/consensus/types/presets/gnosis/eip7594.yaml b/consensus/types/presets/gnosis/fulu.yaml
similarity index 92%
rename from consensus/types/presets/gnosis/eip7594.yaml
rename to consensus/types/presets/gnosis/fulu.yaml
index 813febf26d..e5f3ce0212 100644
--- a/consensus/types/presets/gnosis/eip7594.yaml
+++ b/consensus/types/presets/gnosis/fulu.yaml
@@ -1,4 +1,4 @@
-# Mainnet preset - EIP7594
+# Gnosis preset - Fulu
 
 # Misc
 # ---------------------------------------------------------------
diff --git a/consensus/types/presets/mainnet/altair.yaml b/consensus/types/presets/mainnet/altair.yaml
index 9a17b78032..813ef72122 100644
--- a/consensus/types/presets/mainnet/altair.yaml
+++ b/consensus/types/presets/mainnet/altair.yaml
@@ -22,3 +22,5 @@ EPOCHS_PER_SYNC_COMMITTEE_PERIOD: 256
 # ---------------------------------------------------------------
 # 1
 MIN_SYNC_COMMITTEE_PARTICIPANTS: 1
+# SLOTS_PER_EPOCH * EPOCHS_PER_SYNC_COMMITTEE_PERIOD (= 32 * 256)
+UPDATE_TIMEOUT: 8192
diff --git a/consensus/types/presets/mainnet/deneb.yaml b/consensus/types/presets/mainnet/deneb.yaml
index 0f56b8bdfa..f426d3ae1a 100644
--- a/consensus/types/presets/mainnet/deneb.yaml
+++ b/consensus/types/presets/mainnet/deneb.yaml
@@ -6,7 +6,5 @@
 FIELD_ELEMENTS_PER_BLOB: 4096
 # `uint64(2**12)` (= 4096)
 MAX_BLOB_COMMITMENTS_PER_BLOCK: 4096
-# `uint64(6)`
-MAX_BLOBS_PER_BLOCK: 6
 # `floorlog2(get_generalized_index(BeaconBlockBody, 'blob_kzg_commitments')) + 1 + ceillog2(MAX_BLOB_COMMITMENTS_PER_BLOCK)` = 4 + 1 + 12 = 17
 KZG_COMMITMENT_INCLUSION_PROOF_DEPTH: 17
diff --git a/consensus/types/presets/mainnet/electra.yaml b/consensus/types/presets/mainnet/electra.yaml
index 660ed9b64c..42afbb233e 100644
--- a/consensus/types/presets/mainnet/electra.yaml
+++ b/consensus/types/presets/mainnet/electra.yaml
@@ -10,7 +10,7 @@ MAX_EFFECTIVE_BALANCE_ELECTRA: 2048000000000
 # State list lengths
 # ---------------------------------------------------------------
 # `uint64(2**27)` (= 134,217,728)
-PENDING_BALANCE_DEPOSITS_LIMIT: 134217728
+PENDING_DEPOSITS_LIMIT: 134217728
 # `uint64(2**27)` (= 134,217,728)
 PENDING_PARTIAL_WITHDRAWALS_LIMIT: 134217728
 # `uint64(2**18)` (= 262,144)
@@ -29,12 +29,12 @@ WHISTLEBLOWER_REWARD_QUOTIENT_ELECTRA: 4096
 MAX_ATTESTER_SLASHINGS_ELECTRA: 1
 # `uint64(2**3)` (= 8)
 MAX_ATTESTATIONS_ELECTRA: 8
-# `uint64(2**0)` (= 1)
-MAX_CONSOLIDATION_REQUESTS_PER_PAYLOAD: 1
+# `uint64(2**1)` (= 2)
+MAX_CONSOLIDATION_REQUESTS_PER_PAYLOAD: 2
 
 # Execution
 # ---------------------------------------------------------------
-# 2**13 (= 8192) receipts
+# 2**13 (= 8192) deposit requests
 MAX_DEPOSIT_REQUESTS_PER_PAYLOAD: 8192
 # 2**4 (= 16) withdrawal requests
 MAX_WITHDRAWAL_REQUESTS_PER_PAYLOAD: 16
@@ -43,3 +43,8 @@ MAX_WITHDRAWAL_REQUESTS_PER_PAYLOAD: 16
 # ---------------------------------------------------------------
 # 2**3 ( = 8) pending withdrawals
 MAX_PENDING_PARTIALS_PER_WITHDRAWALS_SWEEP: 8
+
+# Pending deposits processing
+# ---------------------------------------------------------------
+# 2**4 ( = 4) pending deposits
+MAX_PENDING_DEPOSITS_PER_EPOCH: 16
diff --git a/consensus/types/presets/mainnet/eip7594.yaml b/consensus/types/presets/mainnet/fulu.yaml
similarity index 92%
rename from consensus/types/presets/mainnet/eip7594.yaml
rename to consensus/types/presets/mainnet/fulu.yaml
index 813febf26d..394f335f90 100644
--- a/consensus/types/presets/mainnet/eip7594.yaml
+++ b/consensus/types/presets/mainnet/fulu.yaml
@@ -1,4 +1,4 @@
-# Mainnet preset - EIP7594
+# Mainnet preset - Fulu
 
 # Misc
 # ---------------------------------------------------------------
diff --git a/consensus/types/presets/mainnet/phase0.yaml b/consensus/types/presets/mainnet/phase0.yaml
index 02bc96c8cd..00133ba369 100644
--- a/consensus/types/presets/mainnet/phase0.yaml
+++ b/consensus/types/presets/mainnet/phase0.yaml
@@ -85,4 +85,4 @@ MAX_ATTESTATIONS: 128
 # 2**4 (= 16)
 MAX_DEPOSITS: 16
 # 2**4 (= 16)
-MAX_VOLUNTARY_EXITS: 16
+MAX_VOLUNTARY_EXITS: 16
\ No newline at end of file
diff --git a/consensus/types/presets/minimal/altair.yaml b/consensus/types/presets/minimal/altair.yaml
index 88d78bea36..5e472c49cf 100644
--- a/consensus/types/presets/minimal/altair.yaml
+++ b/consensus/types/presets/minimal/altair.yaml
@@ -22,3 +22,5 @@ EPOCHS_PER_SYNC_COMMITTEE_PERIOD: 8
 # ---------------------------------------------------------------
 # 1
 MIN_SYNC_COMMITTEE_PARTICIPANTS: 1
+# SLOTS_PER_EPOCH * EPOCHS_PER_SYNC_COMMITTEE_PERIOD (= 8 * 8)
+UPDATE_TIMEOUT: 64
diff --git a/consensus/types/presets/minimal/deneb.yaml b/consensus/types/presets/minimal/deneb.yaml
index be2b9fadfa..c101de3162 100644
--- a/consensus/types/presets/minimal/deneb.yaml
+++ b/consensus/types/presets/minimal/deneb.yaml
@@ -2,11 +2,9 @@
 
 # Misc
 # ---------------------------------------------------------------
-# [customized]
+# `uint64(4096)`
 FIELD_ELEMENTS_PER_BLOB: 4096
 # [customized]
-MAX_BLOB_COMMITMENTS_PER_BLOCK: 16
-# `uint64(6)`
-MAX_BLOBS_PER_BLOCK: 6
-# [customized] `floorlog2(BLOB_KZG_COMMITMENTS_GINDEX) + 1 + ceillog2(MAX_BLOB_COMMITMENTS_PER_BLOCK)` = 4 + 1 + 4 = 9
-KZG_COMMITMENT_INCLUSION_PROOF_DEPTH: 9
+MAX_BLOB_COMMITMENTS_PER_BLOCK: 32
+# [customized] `floorlog2(get_generalized_index(BeaconBlockBody, 'blob_kzg_commitments')) + 1 + ceillog2(MAX_BLOB_COMMITMENTS_PER_BLOCK)` = 4 + 1 + 5 = 10
+KZG_COMMITMENT_INCLUSION_PROOF_DEPTH: 10
diff --git a/consensus/types/presets/minimal/electra.yaml b/consensus/types/presets/minimal/electra.yaml
index ef1ce494d8..44e4769756 100644
--- a/consensus/types/presets/minimal/electra.yaml
+++ b/consensus/types/presets/minimal/electra.yaml
@@ -10,7 +10,7 @@ MAX_EFFECTIVE_BALANCE_ELECTRA: 2048000000000
 # State list lengths
 # ---------------------------------------------------------------
 # `uint64(2**27)` (= 134,217,728)
-PENDING_BALANCE_DEPOSITS_LIMIT: 134217728
+PENDING_DEPOSITS_LIMIT: 134217728
 # [customized] `uint64(2**6)` (= 64)
 PENDING_PARTIAL_WITHDRAWALS_LIMIT: 64
 # [customized] `uint64(2**6)` (= 64)
@@ -29,8 +29,8 @@ WHISTLEBLOWER_REWARD_QUOTIENT_ELECTRA: 4096
 MAX_ATTESTER_SLASHINGS_ELECTRA: 1
 # `uint64(2**3)` (= 8)
 MAX_ATTESTATIONS_ELECTRA: 8
-# `uint64(2**0)` (= 1)
-MAX_CONSOLIDATION_REQUESTS_PER_PAYLOAD: 1
+# `uint64(2**1)` (= 2)
+MAX_CONSOLIDATION_REQUESTS_PER_PAYLOAD: 2
 
 # Execution
 # ---------------------------------------------------------------
@@ -41,5 +41,10 @@ MAX_WITHDRAWAL_REQUESTS_PER_PAYLOAD: 2
 
 # Withdrawals processing
 # ---------------------------------------------------------------
-# 2**0 ( = 1) pending withdrawals
-MAX_PENDING_PARTIALS_PER_WITHDRAWALS_SWEEP: 1
+# 2**1 ( = 2) pending withdrawals
+MAX_PENDING_PARTIALS_PER_WITHDRAWALS_SWEEP: 2
+
+# Pending deposits processing
+# ---------------------------------------------------------------
+# 2**4 ( = 4) pending deposits
+MAX_PENDING_DEPOSITS_PER_EPOCH: 16
diff --git a/consensus/types/presets/minimal/eip7594.yaml b/consensus/types/presets/minimal/fulu.yaml
similarity index 92%
rename from consensus/types/presets/minimal/eip7594.yaml
rename to consensus/types/presets/minimal/fulu.yaml
index 847719a421..c961eb7f3c 100644
--- a/consensus/types/presets/minimal/eip7594.yaml
+++ b/consensus/types/presets/minimal/fulu.yaml
@@ -1,4 +1,4 @@
-# Minimal preset - EIP7594
+# Minimal preset - Fulu
 
 # Misc
 # ---------------------------------------------------------------
diff --git a/consensus/types/presets/minimal/phase0.yaml b/consensus/types/presets/minimal/phase0.yaml
index 1f75603142..d9a6a2b6c0 100644
--- a/consensus/types/presets/minimal/phase0.yaml
+++ b/consensus/types/presets/minimal/phase0.yaml
@@ -4,11 +4,11 @@
 # ---------------------------------------------------------------
 # [customized] Just 4 committees for slot for testing purposes
 MAX_COMMITTEES_PER_SLOT: 4
-# [customized] unsecure, but fast
+# [customized] insecure, but fast
 TARGET_COMMITTEE_SIZE: 4
 # 2**11 (= 2,048)
 MAX_VALIDATORS_PER_COMMITTEE: 2048
-# [customized] Faster, but unsecure.
+# [customized] Faster, but insecure.
 SHUFFLE_ROUND_COUNT: 10
 # 4
 HYSTERESIS_QUOTIENT: 4
@@ -85,4 +85,4 @@ MAX_ATTESTATIONS: 128
 # 2**4 (= 16)
 MAX_DEPOSITS: 16
 # 2**4 (= 16)
-MAX_VOLUNTARY_EXITS: 16
+MAX_VOLUNTARY_EXITS: 16
\ No newline at end of file
diff --git a/consensus/types/src/attestation.rs b/consensus/types/src/attestation.rs
index 190964736f..276b27b0f8 100644
--- a/consensus/types/src/attestation.rs
+++ b/consensus/types/src/attestation.rs
@@ -12,8 +12,8 @@ use test_random_derive::TestRandom;
 use tree_hash_derive::TreeHash;
 
 use super::{
-    AggregateSignature, AttestationData, BitList, ChainSpec, Domain, EthSpec, Fork, SecretKey,
-    Signature, SignedRoot,
+    AggregateSignature, AttestationData, BitList, ChainSpec, CommitteeIndex, Domain, EthSpec, Fork,
+    SecretKey, Signature, SignedRoot,
 };
 
 #[derive(Debug, PartialEq)]
@@ -24,6 +24,10 @@ pub enum Error {
     IncorrectStateVariant,
     InvalidCommitteeLength,
     InvalidCommitteeIndex,
+    AttesterNotInCommittee(u64),
+    InvalidCommittee,
+    MissingCommittee,
+    NoCommitteeForSlotAndIndex { slot: Slot, index: CommitteeIndex },
 }
 
 impl From<ssz_types::Error> for Error {
@@ -231,6 +235,16 @@ impl<E: EthSpec> Attestation<E> {
             Attestation::Electra(att) => att.aggregation_bits.get(index),
         }
     }
+
+    pub fn to_single_attestation_with_attester_index(
+        &self,
+        attester_index: u64,
+    ) -> Result<SingleAttestation, Error> {
+        match self {
+            Self::Base(_) => Err(Error::IncorrectStateVariant),
+            Self::Electra(attn) => attn.to_single_attestation_with_attester_index(attester_index),
+        }
+    }
 }
 
 impl<E: EthSpec> AttestationRef<'_, E> {
@@ -287,6 +301,14 @@ impl<E: EthSpec> AttestationElectra<E> {
         self.get_committee_indices().first().cloned()
     }
 
+    pub fn get_aggregation_bits(&self) -> Vec<u64> {
+        self.aggregation_bits
+            .iter()
+            .enumerate()
+            .filter_map(|(index, bit)| if bit { Some(index as u64) } else { None })
+            .collect()
+    }
+
     pub fn get_committee_indices(&self) -> Vec<u64> {
         self.committee_bits
             .iter()
@@ -350,6 +372,22 @@ impl<E: EthSpec> AttestationElectra<E> {
             Ok(())
         }
     }
+
+    pub fn to_single_attestation_with_attester_index(
+        &self,
+        attester_index: u64,
+    ) -> Result<SingleAttestation, Error> {
+        let Some(committee_index) = self.committee_index() else {
+            return Err(Error::InvalidCommitteeIndex);
+        };
+
+        Ok(SingleAttestation {
+            committee_index,
+            attester_index,
+            data: self.data.clone(),
+            signature: self.signature.clone(),
+        })
+    }
 }
 
 impl<E: EthSpec> AttestationBase<E> {
@@ -527,6 +565,60 @@ impl<E: EthSpec> ForkVersionDeserialize for Vec<Attestation<E>> {
     }
 }
 
+#[derive(
+    Debug,
+    Clone,
+    Serialize,
+    Deserialize,
+    Decode,
+    Encode,
+    TestRandom,
+    Derivative,
+    arbitrary::Arbitrary,
+    TreeHash,
+    PartialEq,
+)]
+pub struct SingleAttestation {
+    #[serde(with = "serde_utils::quoted_u64")]
+    pub committee_index: u64,
+    #[serde(with = "serde_utils::quoted_u64")]
+    pub attester_index: u64,
+    pub data: AttestationData,
+    pub signature: AggregateSignature,
+}
+
+impl SingleAttestation {
+    pub fn to_attestation<E: EthSpec>(&self, committee: &[usize]) -> Result<Attestation<E>, Error> {
+        let aggregation_bit = committee
+            .iter()
+            .enumerate()
+            .find_map(|(i, &validator_index)| {
+                if self.attester_index as usize == validator_index {
+                    return Some(i);
+                }
+                None
+            })
+            .ok_or(Error::AttesterNotInCommittee(self.attester_index))?;
+
+        let mut committee_bits: BitVector<E::MaxCommitteesPerSlot> = BitVector::default();
+        committee_bits
+            .set(self.committee_index as usize, true)
+            .map_err(|_| Error::InvalidCommitteeIndex)?;
+
+        let mut aggregation_bits =
+            BitList::with_capacity(committee.len()).map_err(|_| Error::InvalidCommitteeLength)?;
+
+        aggregation_bits.set(aggregation_bit, true)?;
+
+        Ok(Attestation::Electra(AttestationElectra {
+            aggregation_bits,
+            committee_bits,
+            data: self.data.clone(),
+            signature: self.signature.clone(),
+        }))
+    }
+}
+
 #[cfg(test)]
 mod tests {
     use super::*;
diff --git a/consensus/types/src/beacon_block.rs b/consensus/types/src/beacon_block.rs
index 801b7dd1c7..6ea897cf1a 100644
--- a/consensus/types/src/beacon_block.rs
+++ b/consensus/types/src/beacon_block.rs
@@ -12,11 +12,11 @@ use test_random_derive::TestRandom;
 use tree_hash::TreeHash;
 use tree_hash_derive::TreeHash;
 
-use self::indexed_attestation::{IndexedAttestationBase, IndexedAttestationElectra};
+use self::indexed_attestation::IndexedAttestationBase;
 
 /// A block of the `BeaconChain`.
 #[superstruct(
-    variants(Base, Altair, Bellatrix, Capella, Deneb, Electra),
+    variants(Base, Altair, Bellatrix, Capella, Deneb, Electra, Fulu),
     variant_attributes(
         derive(
             Debug,
@@ -75,6 +75,8 @@ pub struct BeaconBlock<E: EthSpec, Payload: AbstractExecPayload<E> = FullPayload
     pub body: BeaconBlockBodyDeneb<E, Payload>,
     #[superstruct(only(Electra), partial_getter(rename = "body_electra"))]
     pub body: BeaconBlockBodyElectra<E, Payload>,
+    #[superstruct(only(Fulu), partial_getter(rename = "body_fulu"))]
+    pub body: BeaconBlockBodyFulu<E, Payload>,
 }
 
 pub type BlindedBeaconBlock<E> = BeaconBlock<E, BlindedPayload<E>>;
@@ -127,8 +129,9 @@ impl<E: EthSpec, Payload: AbstractExecPayload<E>> BeaconBlock<E, Payload> {
     /// Usually it's better to prefer `from_ssz_bytes` which will decode the correct variant based
     /// on the fork slot.
     pub fn any_from_ssz_bytes(bytes: &[u8]) -> Result<Self, ssz::DecodeError> {
-        BeaconBlockElectra::from_ssz_bytes(bytes)
-            .map(BeaconBlock::Electra)
+        BeaconBlockFulu::from_ssz_bytes(bytes)
+            .map(BeaconBlock::Fulu)
+            .or_else(|_| BeaconBlockElectra::from_ssz_bytes(bytes).map(BeaconBlock::Electra))
             .or_else(|_| BeaconBlockDeneb::from_ssz_bytes(bytes).map(BeaconBlock::Deneb))
             .or_else(|_| BeaconBlockCapella::from_ssz_bytes(bytes).map(BeaconBlock::Capella))
             .or_else(|_| BeaconBlockBellatrix::from_ssz_bytes(bytes).map(BeaconBlock::Bellatrix))
@@ -226,6 +229,7 @@ impl<'a, E: EthSpec, Payload: AbstractExecPayload<E>> BeaconBlockRef<'a, E, Payl
             BeaconBlockRef::Capella { .. } => ForkName::Capella,
             BeaconBlockRef::Deneb { .. } => ForkName::Deneb,
             BeaconBlockRef::Electra { .. } => ForkName::Electra,
+            BeaconBlockRef::Fulu { .. } => ForkName::Fulu,
         }
     }
 
@@ -495,52 +499,6 @@ impl<E: EthSpec, Payload: AbstractExecPayload<E>> EmptyBlock for BeaconBlockBell
     }
 }
 
-impl<E: EthSpec, Payload: AbstractExecPayload<E>> BeaconBlockCapella<E, Payload> {
-    /// Return a Capella block where the block has maximum size.
-    pub fn full(spec: &ChainSpec) -> Self {
-        let base_block: BeaconBlockBase<_, Payload> = BeaconBlockBase::full(spec);
-        let bls_to_execution_changes = vec![
-            SignedBlsToExecutionChange {
-                message: BlsToExecutionChange {
-                    validator_index: 0,
-                    from_bls_pubkey: PublicKeyBytes::empty(),
-                    to_execution_address: Address::ZERO,
-                },
-                signature: Signature::empty()
-            };
-            E::max_bls_to_execution_changes()
-        ]
-        .into();
-        let sync_aggregate = SyncAggregate {
-            sync_committee_signature: AggregateSignature::empty(),
-            sync_committee_bits: BitVector::default(),
-        };
-        BeaconBlockCapella {
-            slot: spec.genesis_slot,
-            proposer_index: 0,
-            parent_root: Hash256::zero(),
-            state_root: Hash256::zero(),
-            body: BeaconBlockBodyCapella {
-                proposer_slashings: base_block.body.proposer_slashings,
-                attester_slashings: base_block.body.attester_slashings,
-                attestations: base_block.body.attestations,
-                deposits: base_block.body.deposits,
-                voluntary_exits: base_block.body.voluntary_exits,
-                bls_to_execution_changes,
-                sync_aggregate,
-                randao_reveal: Signature::empty(),
-                eth1_data: Eth1Data {
-                    deposit_root: Hash256::zero(),
-                    block_hash: Hash256::zero(),
-                    deposit_count: 0,
-                },
-                graffiti: Graffiti::default(),
-                execution_payload: Payload::Capella::default(),
-            },
-        }
-    }
-}
-
 impl<E: EthSpec, Payload: AbstractExecPayload<E>> EmptyBlock for BeaconBlockCapella<E, Payload> {
     /// Returns an empty Capella block to be used during genesis.
     fn empty(spec: &ChainSpec) -> Self {
@@ -600,79 +558,6 @@ impl<E: EthSpec, Payload: AbstractExecPayload<E>> EmptyBlock for BeaconBlockDene
     }
 }
 
-impl<E: EthSpec, Payload: AbstractExecPayload<E>> BeaconBlockElectra<E, Payload> {
-    /// Return a Electra block where the block has maximum size.
-    pub fn full(spec: &ChainSpec) -> Self {
-        let base_block: BeaconBlockBase<_, Payload> = BeaconBlockBase::full(spec);
-        let indexed_attestation: IndexedAttestationElectra<E> = IndexedAttestationElectra {
-            attesting_indices: VariableList::new(vec![0_u64; E::MaxValidatorsPerSlot::to_usize()])
-                .unwrap(),
-            data: AttestationData::default(),
-            signature: AggregateSignature::empty(),
-        };
-        let attester_slashings = vec![
-            AttesterSlashingElectra {
-                attestation_1: indexed_attestation.clone(),
-                attestation_2: indexed_attestation,
-            };
-            E::max_attester_slashings_electra()
-        ]
-        .into();
-        let attestation = AttestationElectra {
-            aggregation_bits: BitList::with_capacity(E::MaxValidatorsPerSlot::to_usize()).unwrap(),
-            data: AttestationData::default(),
-            signature: AggregateSignature::empty(),
-            committee_bits: BitVector::new(),
-        };
-        let mut attestations_electra = vec![];
-        for _ in 0..E::MaxAttestationsElectra::to_usize() {
-            attestations_electra.push(attestation.clone());
-        }
-
-        let bls_to_execution_changes = vec![
-            SignedBlsToExecutionChange {
-                message: BlsToExecutionChange {
-                    validator_index: 0,
-                    from_bls_pubkey: PublicKeyBytes::empty(),
-                    to_execution_address: Address::ZERO,
-                },
-                signature: Signature::empty()
-            };
-            E::max_bls_to_execution_changes()
-        ]
-        .into();
-        let sync_aggregate = SyncAggregate {
-            sync_committee_signature: AggregateSignature::empty(),
-            sync_committee_bits: BitVector::default(),
-        };
-        BeaconBlockElectra {
-            slot: spec.genesis_slot,
-            proposer_index: 0,
-            parent_root: Hash256::zero(),
-            state_root: Hash256::zero(),
-            body: BeaconBlockBodyElectra {
-                proposer_slashings: base_block.body.proposer_slashings,
-                attester_slashings,
-                attestations: attestations_electra.into(),
-                deposits: base_block.body.deposits,
-                voluntary_exits: base_block.body.voluntary_exits,
-                bls_to_execution_changes,
-                sync_aggregate,
-                randao_reveal: Signature::empty(),
-                eth1_data: Eth1Data {
-                    deposit_root: Hash256::zero(),
-                    block_hash: Hash256::zero(),
-                    deposit_count: 0,
-                },
-                graffiti: Graffiti::default(),
-                execution_payload: Payload::Electra::default(),
-                blob_kzg_commitments: VariableList::empty(),
-                execution_requests: ExecutionRequests::default(),
-            },
-        }
-    }
-}
-
 impl<E: EthSpec, Payload: AbstractExecPayload<E>> EmptyBlock for BeaconBlockElectra<E, Payload> {
     /// Returns an empty Electra block to be used during genesis.
     fn empty(spec: &ChainSpec) -> Self {
@@ -704,6 +589,37 @@ impl<E: EthSpec, Payload: AbstractExecPayload<E>> EmptyBlock for BeaconBlockElec
     }
 }
 
+impl<E: EthSpec, Payload: AbstractExecPayload<E>> EmptyBlock for BeaconBlockFulu<E, Payload> {
+    /// Returns an empty Fulu block to be used during genesis.
+    fn empty(spec: &ChainSpec) -> Self {
+        BeaconBlockFulu {
+            slot: spec.genesis_slot,
+            proposer_index: 0,
+            parent_root: Hash256::zero(),
+            state_root: Hash256::zero(),
+            body: BeaconBlockBodyFulu {
+                randao_reveal: Signature::empty(),
+                eth1_data: Eth1Data {
+                    deposit_root: Hash256::zero(),
+                    block_hash: Hash256::zero(),
+                    deposit_count: 0,
+                },
+                graffiti: Graffiti::default(),
+                proposer_slashings: VariableList::empty(),
+                attester_slashings: VariableList::empty(),
+                attestations: VariableList::empty(),
+                deposits: VariableList::empty(),
+                voluntary_exits: VariableList::empty(),
+                sync_aggregate: SyncAggregate::empty(),
+                execution_payload: Payload::Fulu::default(),
+                bls_to_execution_changes: VariableList::empty(),
+                blob_kzg_commitments: VariableList::empty(),
+                execution_requests: ExecutionRequests::default(),
+            },
+        }
+    }
+}
+
 // We can convert pre-Bellatrix blocks without payloads into blocks "with" payloads.
 impl<E: EthSpec> From<BeaconBlockBase<E, BlindedPayload<E>>>
     for BeaconBlockBase<E, FullPayload<E>>
@@ -785,6 +701,7 @@ impl_from!(BeaconBlockBellatrix, <E, FullPayload<E>>, <E, BlindedPayload<E>>, |b
 impl_from!(BeaconBlockCapella, <E, FullPayload<E>>, <E, BlindedPayload<E>>, |body: BeaconBlockBodyCapella<_, _>| body.into());
 impl_from!(BeaconBlockDeneb, <E, FullPayload<E>>, <E, BlindedPayload<E>>, |body: BeaconBlockBodyDeneb<_, _>| body.into());
 impl_from!(BeaconBlockElectra, <E, FullPayload<E>>, <E, BlindedPayload<E>>, |body: BeaconBlockBodyElectra<_, _>| body.into());
+impl_from!(BeaconBlockFulu, <E, FullPayload<E>>, <E, BlindedPayload<E>>, |body: BeaconBlockBodyFulu<_, _>| body.into());
 
 // We can clone blocks with payloads to blocks without payloads, without cloning the payload.
 macro_rules! impl_clone_as_blinded {
@@ -818,6 +735,7 @@ impl_clone_as_blinded!(BeaconBlockBellatrix, <E, FullPayload<E>>, <E, BlindedPay
 impl_clone_as_blinded!(BeaconBlockCapella, <E, FullPayload<E>>, <E, BlindedPayload<E>>);
 impl_clone_as_blinded!(BeaconBlockDeneb, <E, FullPayload<E>>, <E, BlindedPayload<E>>);
 impl_clone_as_blinded!(BeaconBlockElectra, <E, FullPayload<E>>, <E, BlindedPayload<E>>);
+impl_clone_as_blinded!(BeaconBlockFulu, <E, FullPayload<E>>, <E, BlindedPayload<E>>);
 
 // A reference to a full beacon block can be cloned into a blinded beacon block, without cloning the
 // execution payload.
@@ -988,6 +906,26 @@ mod tests {
         });
     }
 
+    #[test]
+    fn roundtrip_fulu_block() {
+        let rng = &mut XorShiftRng::from_seed([42; 16]);
+        let spec = &ForkName::Fulu.make_genesis_spec(MainnetEthSpec::default_spec());
+
+        let inner_block = BeaconBlockFulu {
+            slot: Slot::random_for_test(rng),
+            proposer_index: u64::random_for_test(rng),
+            parent_root: Hash256::random_for_test(rng),
+            state_root: Hash256::random_for_test(rng),
+            body: BeaconBlockBodyFulu::random_for_test(rng),
+        };
+
+        let block = BeaconBlock::Fulu(inner_block.clone());
+
+        test_ssz_tree_hash_pair_with(&block, &inner_block, |bytes| {
+            BeaconBlock::from_ssz_bytes(bytes, spec)
+        });
+    }
+
     #[test]
     fn decode_base_and_altair() {
         type E = MainnetEthSpec;
@@ -1007,11 +945,14 @@ mod tests {
         let deneb_slot = deneb_epoch.start_slot(E::slots_per_epoch());
         let electra_epoch = deneb_epoch + 1;
         let electra_slot = electra_epoch.start_slot(E::slots_per_epoch());
+        let fulu_epoch = electra_epoch + 1;
+        let fulu_slot = fulu_epoch.start_slot(E::slots_per_epoch());
 
         spec.altair_fork_epoch = Some(altair_epoch);
         spec.capella_fork_epoch = Some(capella_epoch);
         spec.deneb_fork_epoch = Some(deneb_epoch);
         spec.electra_fork_epoch = Some(electra_epoch);
+        spec.fulu_fork_epoch = Some(fulu_epoch);
 
         // BeaconBlockBase
         {
@@ -1122,5 +1063,29 @@ mod tests {
             BeaconBlock::from_ssz_bytes(&bad_block.as_ssz_bytes(), &spec)
                 .expect_err("bad electra block cannot be decoded");
         }
+
+        // BeaconBlockFulu
+        {
+            let good_block = BeaconBlock::Fulu(BeaconBlockFulu {
+                slot: fulu_slot,
+                ..<_>::random_for_test(rng)
+            });
+            // It's invalid to have a Fulu block with a epoch lower than the fork epoch.
+            let _bad_block = {
+                let mut bad = good_block.clone();
+                *bad.slot_mut() = electra_slot;
+                bad
+            };
+
+            assert_eq!(
+                BeaconBlock::from_ssz_bytes(&good_block.as_ssz_bytes(), &spec)
+                    .expect("good fulu block can be decoded"),
+                good_block
+            );
+            // TODO(fulu): Uncomment once Fulu has features since without features
+            // and with an Electra slot it decodes successfully to Electra.
+            //BeaconBlock::from_ssz_bytes(&bad_block.as_ssz_bytes(), &spec)
+            //    .expect_err("bad fulu block cannot be decoded");
+        }
     }
 }
diff --git a/consensus/types/src/beacon_block_body.rs b/consensus/types/src/beacon_block_body.rs
index b896dc4693..3f75790a35 100644
--- a/consensus/types/src/beacon_block_body.rs
+++ b/consensus/types/src/beacon_block_body.rs
@@ -13,8 +13,6 @@ use tree_hash_derive::TreeHash;
 
 pub type KzgCommitments<E> =
     VariableList<KzgCommitment, <E as EthSpec>::MaxBlobCommitmentsPerBlock>;
-pub type KzgCommitmentOpts<E> =
-    FixedVector<Option<KzgCommitment>, <E as EthSpec>::MaxBlobsPerBlock>;
 
 /// The number of leaves (including padding) on the `BeaconBlockBody` Merkle tree.
 ///
@@ -30,7 +28,7 @@ pub const BLOB_KZG_COMMITMENTS_INDEX: usize = 11;
 ///
 /// This *superstruct* abstracts over the hard-fork.
 #[superstruct(
-    variants(Base, Altair, Bellatrix, Capella, Deneb, Electra),
+    variants(Base, Altair, Bellatrix, Capella, Deneb, Electra, Fulu),
     variant_attributes(
         derive(
             Debug,
@@ -58,6 +56,7 @@ pub const BLOB_KZG_COMMITMENTS_INDEX: usize = 11;
         Capella(metastruct(mappings(beacon_block_body_capella_fields(groups(fields))))),
         Deneb(metastruct(mappings(beacon_block_body_deneb_fields(groups(fields))))),
         Electra(metastruct(mappings(beacon_block_body_electra_fields(groups(fields))))),
+        Fulu(metastruct(mappings(beacon_block_body_fulu_fields(groups(fields)))))
     ),
     cast_error(ty = "Error", expr = "Error::IncorrectStateVariant"),
     partial_getter_error(ty = "Error", expr = "Error::IncorrectStateVariant")
@@ -77,7 +76,10 @@ pub struct BeaconBlockBody<E: EthSpec, Payload: AbstractExecPayload<E> = FullPay
         partial_getter(rename = "attester_slashings_base")
     )]
     pub attester_slashings: VariableList<AttesterSlashingBase<E>, E::MaxAttesterSlashings>,
-    #[superstruct(only(Electra), partial_getter(rename = "attester_slashings_electra"))]
+    #[superstruct(
+        only(Electra, Fulu),
+        partial_getter(rename = "attester_slashings_electra")
+    )]
     pub attester_slashings:
         VariableList<AttesterSlashingElectra<E>, E::MaxAttesterSlashingsElectra>,
     #[superstruct(
@@ -85,11 +87,11 @@ pub struct BeaconBlockBody<E: EthSpec, Payload: AbstractExecPayload<E> = FullPay
         partial_getter(rename = "attestations_base")
     )]
     pub attestations: VariableList<AttestationBase<E>, E::MaxAttestations>,
-    #[superstruct(only(Electra), partial_getter(rename = "attestations_electra"))]
+    #[superstruct(only(Electra, Fulu), partial_getter(rename = "attestations_electra"))]
     pub attestations: VariableList<AttestationElectra<E>, E::MaxAttestationsElectra>,
     pub deposits: VariableList<Deposit, E::MaxDeposits>,
     pub voluntary_exits: VariableList<SignedVoluntaryExit, E::MaxVoluntaryExits>,
-    #[superstruct(only(Altair, Bellatrix, Capella, Deneb, Electra))]
+    #[superstruct(only(Altair, Bellatrix, Capella, Deneb, Electra, Fulu))]
     pub sync_aggregate: SyncAggregate<E>,
     // We flatten the execution payload so that serde can use the name of the inner type,
     // either `execution_payload` for full payloads, or `execution_payload_header` for blinded
@@ -109,12 +111,15 @@ pub struct BeaconBlockBody<E: EthSpec, Payload: AbstractExecPayload<E> = FullPay
     #[superstruct(only(Electra), partial_getter(rename = "execution_payload_electra"))]
     #[serde(flatten)]
     pub execution_payload: Payload::Electra,
-    #[superstruct(only(Capella, Deneb, Electra))]
+    #[superstruct(only(Fulu), partial_getter(rename = "execution_payload_fulu"))]
+    #[serde(flatten)]
+    pub execution_payload: Payload::Fulu,
+    #[superstruct(only(Capella, Deneb, Electra, Fulu))]
     pub bls_to_execution_changes:
         VariableList<SignedBlsToExecutionChange, E::MaxBlsToExecutionChanges>,
-    #[superstruct(only(Deneb, Electra))]
+    #[superstruct(only(Deneb, Electra, Fulu))]
     pub blob_kzg_commitments: KzgCommitments<E>,
-    #[superstruct(only(Electra))]
+    #[superstruct(only(Electra, Fulu))]
     pub execution_requests: ExecutionRequests<E>,
     #[superstruct(only(Base, Altair))]
     #[metastruct(exclude_from(fields))]
@@ -144,6 +149,7 @@ impl<'a, E: EthSpec, Payload: AbstractExecPayload<E>> BeaconBlockBodyRef<'a, E,
             Self::Capella(body) => Ok(Payload::Ref::from(&body.execution_payload)),
             Self::Deneb(body) => Ok(Payload::Ref::from(&body.execution_payload)),
             Self::Electra(body) => Ok(Payload::Ref::from(&body.execution_payload)),
+            Self::Fulu(body) => Ok(Payload::Ref::from(&body.execution_payload)),
         }
     }
 
@@ -174,6 +180,10 @@ impl<'a, E: EthSpec, Payload: AbstractExecPayload<E>> BeaconBlockBodyRef<'a, E,
                 beacon_block_body_electra_fields!(body, |_, field| leaves
                     .push(field.tree_hash_root()));
             }
+            Self::Fulu(body) => {
+                beacon_block_body_fulu_fields!(body, |_, field| leaves
+                    .push(field.tree_hash_root()));
+            }
         }
         leaves
     }
@@ -202,7 +212,7 @@ impl<'a, E: EthSpec, Payload: AbstractExecPayload<E>> BeaconBlockBodyRef<'a, E,
             Self::Base(_) | Self::Altair(_) | Self::Bellatrix(_) | Self::Capella(_) => {
                 Err(Error::IncorrectStateVariant)
             }
-            Self::Deneb(_) | Self::Electra(_) => {
+            Self::Deneb(_) | Self::Electra(_) | Self::Fulu(_) => {
                 // We compute the branches by generating 2 merkle trees:
                 // 1. Merkle tree for the `blob_kzg_commitments` List object
                 // 2. Merkle tree for the `BeaconBlockBody` container
@@ -283,7 +293,7 @@ impl<'a, E: EthSpec, Payload: AbstractExecPayload<E>> BeaconBlockBodyRef<'a, E,
     /// Return `true` if this block body has a non-zero number of blobs.
     pub fn has_blobs(self) -> bool {
         self.blob_kzg_commitments()
-            .map_or(false, |blobs| !blobs.is_empty())
+            .is_ok_and(|blobs| !blobs.is_empty())
     }
 
     pub fn attestations_len(&self) -> usize {
@@ -294,6 +304,7 @@ impl<'a, E: EthSpec, Payload: AbstractExecPayload<E>> BeaconBlockBodyRef<'a, E,
             Self::Capella(body) => body.attestations.len(),
             Self::Deneb(body) => body.attestations.len(),
             Self::Electra(body) => body.attestations.len(),
+            Self::Fulu(body) => body.attestations.len(),
         }
     }
 
@@ -305,6 +316,7 @@ impl<'a, E: EthSpec, Payload: AbstractExecPayload<E>> BeaconBlockBodyRef<'a, E,
             Self::Capella(body) => body.attester_slashings.len(),
             Self::Deneb(body) => body.attester_slashings.len(),
             Self::Electra(body) => body.attester_slashings.len(),
+            Self::Fulu(body) => body.attester_slashings.len(),
         }
     }
 
@@ -316,6 +328,7 @@ impl<'a, E: EthSpec, Payload: AbstractExecPayload<E>> BeaconBlockBodyRef<'a, E,
             Self::Capella(body) => Box::new(body.attestations.iter().map(AttestationRef::Base)),
             Self::Deneb(body) => Box::new(body.attestations.iter().map(AttestationRef::Base)),
             Self::Electra(body) => Box::new(body.attestations.iter().map(AttestationRef::Electra)),
+            Self::Fulu(body) => Box::new(body.attestations.iter().map(AttestationRef::Electra)),
         }
     }
 
@@ -351,6 +364,11 @@ impl<'a, E: EthSpec, Payload: AbstractExecPayload<E>> BeaconBlockBodyRef<'a, E,
                     .iter()
                     .map(AttesterSlashingRef::Electra),
             ),
+            Self::Fulu(body) => Box::new(
+                body.attester_slashings
+                    .iter()
+                    .map(AttesterSlashingRef::Electra),
+            ),
         }
     }
 }
@@ -376,6 +394,9 @@ impl<'a, E: EthSpec, Payload: AbstractExecPayload<E>> BeaconBlockBodyRefMut<'a,
             Self::Electra(body) => {
                 Box::new(body.attestations.iter_mut().map(AttestationRefMut::Electra))
             }
+            Self::Fulu(body) => {
+                Box::new(body.attestations.iter_mut().map(AttestationRefMut::Electra))
+            }
         }
     }
 }
@@ -390,6 +411,7 @@ impl<E: EthSpec, Payload: AbstractExecPayload<E>> BeaconBlockBodyRef<'_, E, Payl
             BeaconBlockBodyRef::Capella { .. } => ForkName::Capella,
             BeaconBlockBodyRef::Deneb { .. } => ForkName::Deneb,
             BeaconBlockBodyRef::Electra { .. } => ForkName::Electra,
+            BeaconBlockBodyRef::Fulu { .. } => ForkName::Fulu,
         }
     }
 }
@@ -704,6 +726,52 @@ impl<E: EthSpec> From<BeaconBlockBodyElectra<E, FullPayload<E>>>
     }
 }
 
+impl<E: EthSpec> From<BeaconBlockBodyFulu<E, FullPayload<E>>>
+    for (
+        BeaconBlockBodyFulu<E, BlindedPayload<E>>,
+        Option<ExecutionPayloadFulu<E>>,
+    )
+{
+    fn from(body: BeaconBlockBodyFulu<E, FullPayload<E>>) -> Self {
+        let BeaconBlockBodyFulu {
+            randao_reveal,
+            eth1_data,
+            graffiti,
+            proposer_slashings,
+            attester_slashings,
+            attestations,
+            deposits,
+            voluntary_exits,
+            sync_aggregate,
+            execution_payload: FullPayloadFulu { execution_payload },
+            bls_to_execution_changes,
+            blob_kzg_commitments,
+            execution_requests,
+        } = body;
+
+        (
+            BeaconBlockBodyFulu {
+                randao_reveal,
+                eth1_data,
+                graffiti,
+                proposer_slashings,
+                attester_slashings,
+                attestations,
+                deposits,
+                voluntary_exits,
+                sync_aggregate,
+                execution_payload: BlindedPayloadFulu {
+                    execution_payload_header: From::from(&execution_payload),
+                },
+                bls_to_execution_changes,
+                blob_kzg_commitments: blob_kzg_commitments.clone(),
+                execution_requests,
+            },
+            Some(execution_payload),
+        )
+    }
+}
+
 // We can clone a full block into a blinded block, without cloning the payload.
 impl<E: EthSpec> BeaconBlockBodyBase<E, FullPayload<E>> {
     pub fn clone_as_blinded(&self) -> BeaconBlockBodyBase<E, BlindedPayload<E>> {
@@ -859,6 +927,44 @@ impl<E: EthSpec> BeaconBlockBodyElectra<E, FullPayload<E>> {
     }
 }
 
+impl<E: EthSpec> BeaconBlockBodyFulu<E, FullPayload<E>> {
+    pub fn clone_as_blinded(&self) -> BeaconBlockBodyFulu<E, BlindedPayload<E>> {
+        let BeaconBlockBodyFulu {
+            randao_reveal,
+            eth1_data,
+            graffiti,
+            proposer_slashings,
+            attester_slashings,
+            attestations,
+            deposits,
+            voluntary_exits,
+            sync_aggregate,
+            execution_payload: FullPayloadFulu { execution_payload },
+            bls_to_execution_changes,
+            blob_kzg_commitments,
+            execution_requests,
+        } = self;
+
+        BeaconBlockBodyFulu {
+            randao_reveal: randao_reveal.clone(),
+            eth1_data: eth1_data.clone(),
+            graffiti: *graffiti,
+            proposer_slashings: proposer_slashings.clone(),
+            attester_slashings: attester_slashings.clone(),
+            attestations: attestations.clone(),
+            deposits: deposits.clone(),
+            voluntary_exits: voluntary_exits.clone(),
+            sync_aggregate: sync_aggregate.clone(),
+            execution_payload: BlindedPayloadFulu {
+                execution_payload_header: execution_payload.into(),
+            },
+            bls_to_execution_changes: bls_to_execution_changes.clone(),
+            blob_kzg_commitments: blob_kzg_commitments.clone(),
+            execution_requests: execution_requests.clone(),
+        }
+    }
+}
+
 impl<E: EthSpec> From<BeaconBlockBody<E, FullPayload<E>>>
     for (
         BeaconBlockBody<E, BlindedPayload<E>>,
diff --git a/consensus/types/src/beacon_state.rs b/consensus/types/src/beacon_state.rs
index e78febaf6c..f1adafd9ee 100644
--- a/consensus/types/src/beacon_state.rs
+++ b/consensus/types/src/beacon_state.rs
@@ -48,6 +48,7 @@ mod tests;
 
 pub const CACHED_EPOCHS: usize = 3;
 const MAX_RANDOM_BYTE: u64 = (1 << 8) - 1;
+const MAX_RANDOM_VALUE: u64 = (1 << 16) - 1;
 
 pub type Validators<E> = List<Validator, <E as EthSpec>::ValidatorRegistryLimit>;
 pub type Balances<E> = List<u64, <E as EthSpec>::ValidatorRegistryLimit>;
@@ -162,7 +163,7 @@ pub enum Error {
     InvalidFlagIndex(usize),
     MerkleTreeError(merkle_proof::MerkleTreeError),
     PartialWithdrawalCountInvalid(usize),
-    NonExecutionAddresWithdrawalCredential,
+    NonExecutionAddressWithdrawalCredential,
     NoCommitteeFound(CommitteeIndex),
     InvalidCommitteeIndex(CommitteeIndex),
     InvalidSelectionProof {
@@ -225,7 +226,7 @@ impl From<BeaconStateHash> for Hash256 {
 ///
 /// https://github.com/sigp/milhouse/issues/43
 #[superstruct(
-    variants(Base, Altair, Bellatrix, Capella, Deneb, Electra),
+    variants(Base, Altair, Bellatrix, Capella, Deneb, Electra, Fulu),
     variant_attributes(
         derive(
             Derivative,
@@ -328,6 +329,20 @@ impl From<BeaconStateHash> for Hash256 {
                 groups(tree_lists)
             )),
             num_fields(all()),
+        )),
+        Fulu(metastruct(
+            mappings(
+                map_beacon_state_fulu_fields(),
+                map_beacon_state_fulu_tree_list_fields(mutable, fallible, groups(tree_lists)),
+                map_beacon_state_fulu_tree_list_fields_immutable(groups(tree_lists)),
+            ),
+            bimappings(bimap_beacon_state_fulu_tree_list_fields(
+                other_type = "BeaconStateFulu",
+                self_mutable,
+                fallible,
+                groups(tree_lists)
+            )),
+            num_fields(all()),
         ))
     ),
     cast_error(ty = "Error", expr = "Error::IncorrectStateVariant"),
@@ -410,11 +425,11 @@ where
 
     // Participation (Altair and later)
     #[compare_fields(as_iter)]
-    #[superstruct(only(Altair, Bellatrix, Capella, Deneb, Electra))]
+    #[superstruct(only(Altair, Bellatrix, Capella, Deneb, Electra, Fulu))]
     #[test_random(default)]
     #[compare_fields(as_iter)]
     pub previous_epoch_participation: List<ParticipationFlags, E::ValidatorRegistryLimit>,
-    #[superstruct(only(Altair, Bellatrix, Capella, Deneb, Electra))]
+    #[superstruct(only(Altair, Bellatrix, Capella, Deneb, Electra, Fulu))]
     #[test_random(default)]
     pub current_epoch_participation: List<ParticipationFlags, E::ValidatorRegistryLimit>,
 
@@ -434,15 +449,15 @@ where
 
     // Inactivity
     #[serde(with = "ssz_types::serde_utils::quoted_u64_var_list")]
-    #[superstruct(only(Altair, Bellatrix, Capella, Deneb, Electra))]
+    #[superstruct(only(Altair, Bellatrix, Capella, Deneb, Electra, Fulu))]
     #[test_random(default)]
     pub inactivity_scores: List<u64, E::ValidatorRegistryLimit>,
 
     // Light-client sync committees
-    #[superstruct(only(Altair, Bellatrix, Capella, Deneb, Electra))]
+    #[superstruct(only(Altair, Bellatrix, Capella, Deneb, Electra, Fulu))]
     #[metastruct(exclude_from(tree_lists))]
     pub current_sync_committee: Arc<SyncCommittee<E>>,
-    #[superstruct(only(Altair, Bellatrix, Capella, Deneb, Electra))]
+    #[superstruct(only(Altair, Bellatrix, Capella, Deneb, Electra, Fulu))]
     #[metastruct(exclude_from(tree_lists))]
     pub next_sync_committee: Arc<SyncCommittee<E>>,
 
@@ -471,56 +486,62 @@ where
     )]
     #[metastruct(exclude_from(tree_lists))]
     pub latest_execution_payload_header: ExecutionPayloadHeaderElectra<E>,
+    #[superstruct(
+        only(Fulu),
+        partial_getter(rename = "latest_execution_payload_header_fulu")
+    )]
+    #[metastruct(exclude_from(tree_lists))]
+    pub latest_execution_payload_header: ExecutionPayloadHeaderFulu<E>,
 
     // Capella
-    #[superstruct(only(Capella, Deneb, Electra), partial_getter(copy))]
+    #[superstruct(only(Capella, Deneb, Electra, Fulu), partial_getter(copy))]
     #[serde(with = "serde_utils::quoted_u64")]
     #[metastruct(exclude_from(tree_lists))]
     pub next_withdrawal_index: u64,
-    #[superstruct(only(Capella, Deneb, Electra), partial_getter(copy))]
+    #[superstruct(only(Capella, Deneb, Electra, Fulu), partial_getter(copy))]
     #[serde(with = "serde_utils::quoted_u64")]
     #[metastruct(exclude_from(tree_lists))]
     pub next_withdrawal_validator_index: u64,
     // Deep history valid from Capella onwards.
-    #[superstruct(only(Capella, Deneb, Electra))]
+    #[superstruct(only(Capella, Deneb, Electra, Fulu))]
     #[test_random(default)]
     pub historical_summaries: List<HistoricalSummary, E::HistoricalRootsLimit>,
 
     // Electra
-    #[superstruct(only(Electra), partial_getter(copy))]
+    #[superstruct(only(Electra, Fulu), partial_getter(copy))]
     #[metastruct(exclude_from(tree_lists))]
     #[serde(with = "serde_utils::quoted_u64")]
     pub deposit_requests_start_index: u64,
-    #[superstruct(only(Electra), partial_getter(copy))]
+    #[superstruct(only(Electra, Fulu), partial_getter(copy))]
     #[metastruct(exclude_from(tree_lists))]
     #[serde(with = "serde_utils::quoted_u64")]
     pub deposit_balance_to_consume: u64,
-    #[superstruct(only(Electra), partial_getter(copy))]
+    #[superstruct(only(Electra, Fulu), partial_getter(copy))]
     #[metastruct(exclude_from(tree_lists))]
     #[serde(with = "serde_utils::quoted_u64")]
     pub exit_balance_to_consume: u64,
-    #[superstruct(only(Electra), partial_getter(copy))]
+    #[superstruct(only(Electra, Fulu), partial_getter(copy))]
     #[metastruct(exclude_from(tree_lists))]
     pub earliest_exit_epoch: Epoch,
-    #[superstruct(only(Electra), partial_getter(copy))]
+    #[superstruct(only(Electra, Fulu), partial_getter(copy))]
     #[metastruct(exclude_from(tree_lists))]
     #[serde(with = "serde_utils::quoted_u64")]
     pub consolidation_balance_to_consume: u64,
-    #[superstruct(only(Electra), partial_getter(copy))]
+    #[superstruct(only(Electra, Fulu), partial_getter(copy))]
     #[metastruct(exclude_from(tree_lists))]
     pub earliest_consolidation_epoch: Epoch,
     #[compare_fields(as_iter)]
     #[test_random(default)]
-    #[superstruct(only(Electra))]
+    #[superstruct(only(Electra, Fulu))]
     pub pending_deposits: List<PendingDeposit, E::PendingDepositsLimit>,
     #[compare_fields(as_iter)]
     #[test_random(default)]
-    #[superstruct(only(Electra))]
+    #[superstruct(only(Electra, Fulu))]
     pub pending_partial_withdrawals:
         List<PendingPartialWithdrawal, E::PendingPartialWithdrawalsLimit>,
     #[compare_fields(as_iter)]
     #[test_random(default)]
-    #[superstruct(only(Electra))]
+    #[superstruct(only(Electra, Fulu))]
     pub pending_consolidations: List<PendingConsolidation, E::PendingConsolidationsLimit>,
 
     // Caching (not in the spec)
@@ -661,6 +682,7 @@ impl<E: EthSpec> BeaconState<E> {
             BeaconState::Capella { .. } => ForkName::Capella,
             BeaconState::Deneb { .. } => ForkName::Deneb,
             BeaconState::Electra { .. } => ForkName::Electra,
+            BeaconState::Fulu { .. } => ForkName::Fulu,
         }
     }
 
@@ -952,6 +974,11 @@ impl<E: EthSpec> BeaconState<E> {
         }
 
         let max_effective_balance = spec.max_effective_balance_for_fork(self.fork_name_unchecked());
+        let max_random_value = if self.fork_name_unchecked().electra_enabled() {
+            MAX_RANDOM_VALUE
+        } else {
+            MAX_RANDOM_BYTE
+        };
 
         let mut i = 0;
         loop {
@@ -965,10 +992,10 @@ impl<E: EthSpec> BeaconState<E> {
             let candidate_index = *indices
                 .get(shuffled_index)
                 .ok_or(Error::ShuffleIndexOutOfBounds(shuffled_index))?;
-            let random_byte = Self::shuffling_random_byte(i, seed)?;
+            let random_value = self.shuffling_random_value(i, seed)?;
             let effective_balance = self.get_effective_balance(candidate_index)?;
-            if effective_balance.safe_mul(MAX_RANDOM_BYTE)?
-                >= max_effective_balance.safe_mul(u64::from(random_byte))?
+            if effective_balance.safe_mul(max_random_value)?
+                >= max_effective_balance.safe_mul(random_value)?
             {
                 return Ok(candidate_index);
             }
@@ -976,6 +1003,19 @@ impl<E: EthSpec> BeaconState<E> {
         }
     }
 
+    /// Fork-aware abstraction for the shuffling.
+    ///
+    /// In Electra and later, the random value is a 16-bit integer stored in a `u64`.
+    ///
+    /// Prior to Electra, the random value is an 8-bit integer stored in a `u64`.
+    fn shuffling_random_value(&self, i: usize, seed: &[u8]) -> Result<u64, Error> {
+        if self.fork_name_unchecked().electra_enabled() {
+            Self::shuffling_random_u16_electra(i, seed).map(u64::from)
+        } else {
+            Self::shuffling_random_byte(i, seed).map(u64::from)
+        }
+    }
+
     /// Get a random byte from the given `seed`.
     ///
     /// Used by the proposer & sync committee selection functions.
@@ -989,6 +1029,21 @@ impl<E: EthSpec> BeaconState<E> {
             .ok_or(Error::ShuffleIndexOutOfBounds(index))
     }
 
+    /// Get two random bytes from the given `seed`.
+    ///
+    /// This is used in place of `shuffling_random_byte` from Electra onwards.
+    fn shuffling_random_u16_electra(i: usize, seed: &[u8]) -> Result<u16, Error> {
+        let mut preimage = seed.to_vec();
+        preimage.append(&mut int_to_bytes8(i.safe_div(16)? as u64));
+        let offset = i.safe_rem(16)?.safe_mul(2)?;
+        hash(&preimage)
+            .get(offset..offset.safe_add(2)?)
+            .ok_or(Error::ShuffleIndexOutOfBounds(offset))?
+            .try_into()
+            .map(u16::from_le_bytes)
+            .map_err(|_| Error::ShuffleIndexOutOfBounds(offset))
+    }
+
     /// Convenience accessor for the `execution_payload_header` as an `ExecutionPayloadHeaderRef`.
     pub fn latest_execution_payload_header(&self) -> Result<ExecutionPayloadHeaderRef<E>, Error> {
         match self {
@@ -1005,6 +1060,9 @@ impl<E: EthSpec> BeaconState<E> {
             BeaconState::Electra(state) => Ok(ExecutionPayloadHeaderRef::Electra(
                 &state.latest_execution_payload_header,
             )),
+            BeaconState::Fulu(state) => Ok(ExecutionPayloadHeaderRef::Fulu(
+                &state.latest_execution_payload_header,
+            )),
         }
     }
 
@@ -1025,6 +1083,9 @@ impl<E: EthSpec> BeaconState<E> {
             BeaconState::Electra(state) => Ok(ExecutionPayloadHeaderRefMut::Electra(
                 &mut state.latest_execution_payload_header,
             )),
+            BeaconState::Fulu(state) => Ok(ExecutionPayloadHeaderRefMut::Fulu(
+                &mut state.latest_execution_payload_header,
+            )),
         }
     }
 
@@ -1150,6 +1211,11 @@ impl<E: EthSpec> BeaconState<E> {
 
         let seed = self.get_seed(epoch, Domain::SyncCommittee, spec)?;
         let max_effective_balance = spec.max_effective_balance_for_fork(self.fork_name_unchecked());
+        let max_random_value = if self.fork_name_unchecked().electra_enabled() {
+            MAX_RANDOM_VALUE
+        } else {
+            MAX_RANDOM_BYTE
+        };
 
         let mut i = 0;
         let mut sync_committee_indices = Vec::with_capacity(E::SyncCommitteeSize::to_usize());
@@ -1164,10 +1230,10 @@ impl<E: EthSpec> BeaconState<E> {
             let candidate_index = *active_validator_indices
                 .get(shuffled_index)
                 .ok_or(Error::ShuffleIndexOutOfBounds(shuffled_index))?;
-            let random_byte = Self::shuffling_random_byte(i, seed.as_slice())?;
+            let random_value = self.shuffling_random_value(i, seed.as_slice())?;
             let effective_balance = self.get_validator(candidate_index)?.effective_balance;
-            if effective_balance.safe_mul(MAX_RANDOM_BYTE)?
-                >= max_effective_balance.safe_mul(u64::from(random_byte))?
+            if effective_balance.safe_mul(max_random_value)?
+                >= max_effective_balance.safe_mul(random_value)?
             {
                 sync_committee_indices.push(candidate_index);
             }
@@ -1538,6 +1604,16 @@ impl<E: EthSpec> BeaconState<E> {
                 &mut state.exit_cache,
                 &mut state.epoch_cache,
             )),
+            BeaconState::Fulu(state) => Ok((
+                &mut state.validators,
+                &mut state.balances,
+                &state.previous_epoch_participation,
+                &state.current_epoch_participation,
+                &mut state.inactivity_scores,
+                &mut state.progressive_balances_cache,
+                &mut state.exit_cache,
+                &mut state.epoch_cache,
+            )),
         }
     }
 
@@ -1719,10 +1795,12 @@ impl<E: EthSpec> BeaconState<E> {
             | BeaconState::Altair(_)
             | BeaconState::Bellatrix(_)
             | BeaconState::Capella(_) => self.get_validator_churn_limit(spec)?,
-            BeaconState::Deneb(_) | BeaconState::Electra(_) => std::cmp::min(
-                spec.max_per_epoch_activation_churn_limit,
-                self.get_validator_churn_limit(spec)?,
-            ),
+            BeaconState::Deneb(_) | BeaconState::Electra(_) | BeaconState::Fulu(_) => {
+                std::cmp::min(
+                    spec.max_per_epoch_activation_churn_limit,
+                    self.get_validator_churn_limit(spec)?,
+                )
+            }
         })
     }
 
@@ -1861,6 +1939,7 @@ impl<E: EthSpec> BeaconState<E> {
                 BeaconState::Capella(state) => Ok(&mut state.current_epoch_participation),
                 BeaconState::Deneb(state) => Ok(&mut state.current_epoch_participation),
                 BeaconState::Electra(state) => Ok(&mut state.current_epoch_participation),
+                BeaconState::Fulu(state) => Ok(&mut state.current_epoch_participation),
             }
         } else if epoch == previous_epoch {
             match self {
@@ -1870,6 +1949,7 @@ impl<E: EthSpec> BeaconState<E> {
                 BeaconState::Capella(state) => Ok(&mut state.previous_epoch_participation),
                 BeaconState::Deneb(state) => Ok(&mut state.previous_epoch_participation),
                 BeaconState::Electra(state) => Ok(&mut state.previous_epoch_participation),
+                BeaconState::Fulu(state) => Ok(&mut state.previous_epoch_participation),
             }
         } else {
             Err(BeaconStateError::EpochOutOfBounds)
@@ -1934,7 +2014,7 @@ impl<E: EthSpec> BeaconState<E> {
     pub fn committee_cache_is_initialized(&self, relative_epoch: RelativeEpoch) -> bool {
         let i = Self::committee_cache_index(relative_epoch);
 
-        self.committee_cache_at_index(i).map_or(false, |cache| {
+        self.committee_cache_at_index(i).is_ok_and(|cache| {
             cache.is_initialized_at(relative_epoch.into_epoch(self.current_epoch()))
         })
     }
@@ -2123,6 +2203,11 @@ impl<E: EthSpec> BeaconState<E> {
                     }
                 );
             }
+            Self::Fulu(self_inner) => {
+                map_beacon_state_fulu_tree_list_fields_immutable!(self_inner, |_, self_field| {
+                    any_pending_mutations |= self_field.has_pending_updates();
+                });
+            }
         };
         any_pending_mutations
     }
@@ -2207,7 +2292,7 @@ impl<E: EthSpec> BeaconState<E> {
 
     // ******* Electra accessors *******
 
-    /// Return the churn limit for the current epoch.
+    /// Return the churn limit for the current epoch.
     pub fn get_balance_churn_limit(&self, spec: &ChainSpec) -> Result<u64, Error> {
         let total_active_balance = self.get_total_active_balance()?;
         let churn = std::cmp::max(
@@ -2237,7 +2322,7 @@ impl<E: EthSpec> BeaconState<E> {
         for withdrawal in self
             .pending_partial_withdrawals()?
             .iter()
-            .filter(|withdrawal| withdrawal.index as usize == validator_index)
+            .filter(|withdrawal| withdrawal.validator_index as usize == validator_index)
         {
             pending_balance.safe_add_assign(withdrawal.amount)?;
         }
@@ -2316,12 +2401,20 @@ impl<E: EthSpec> BeaconState<E> {
             exit_balance_to_consume
                 .safe_add_assign(additional_epochs.safe_mul(per_epoch_churn)?)?;
         }
-        let state = self.as_electra_mut()?;
-        // Consume the balance and update state variables
-        state.exit_balance_to_consume = exit_balance_to_consume.safe_sub(exit_balance)?;
-        state.earliest_exit_epoch = earliest_exit_epoch;
-
-        Ok(state.earliest_exit_epoch)
+        match self {
+            BeaconState::Base(_)
+            | BeaconState::Altair(_)
+            | BeaconState::Bellatrix(_)
+            | BeaconState::Capella(_)
+            | BeaconState::Deneb(_) => Err(Error::IncorrectStateVariant),
+            BeaconState::Electra(_) | BeaconState::Fulu(_) => {
+                // Consume the balance and update state variables
+                *self.exit_balance_to_consume_mut()? =
+                    exit_balance_to_consume.safe_sub(exit_balance)?;
+                *self.earliest_exit_epoch_mut()? = earliest_exit_epoch;
+                self.earliest_exit_epoch()
+            }
+        }
     }
 
     pub fn compute_consolidation_epoch_and_update_churn(
@@ -2355,13 +2448,20 @@ impl<E: EthSpec> BeaconState<E> {
             consolidation_balance_to_consume
                 .safe_add_assign(additional_epochs.safe_mul(per_epoch_consolidation_churn)?)?;
         }
-        // Consume the balance and update state variables
-        let state = self.as_electra_mut()?;
-        state.consolidation_balance_to_consume =
-            consolidation_balance_to_consume.safe_sub(consolidation_balance)?;
-        state.earliest_consolidation_epoch = earliest_consolidation_epoch;
-
-        Ok(state.earliest_consolidation_epoch)
+        match self {
+            BeaconState::Base(_)
+            | BeaconState::Altair(_)
+            | BeaconState::Bellatrix(_)
+            | BeaconState::Capella(_)
+            | BeaconState::Deneb(_) => Err(Error::IncorrectStateVariant),
+            BeaconState::Electra(_) | BeaconState::Fulu(_) => {
+                // Consume the balance and update state variables.
+                *self.consolidation_balance_to_consume_mut()? =
+                    consolidation_balance_to_consume.safe_sub(consolidation_balance)?;
+                *self.earliest_consolidation_epoch_mut()? = earliest_consolidation_epoch;
+                self.earliest_consolidation_epoch()
+            }
+        }
     }
 
     #[allow(clippy::arithmetic_side_effects)]
@@ -2417,6 +2517,14 @@ impl<E: EthSpec> BeaconState<E> {
                 );
             }
             (Self::Electra(_), _) => (),
+            (Self::Fulu(self_inner), Self::Fulu(base_inner)) => {
+                bimap_beacon_state_fulu_tree_list_fields!(
+                    self_inner,
+                    base_inner,
+                    |_, self_field, base_field| { self_field.rebase_on(base_field) }
+                );
+            }
+            (Self::Fulu(_), _) => (),
         }
 
         // Use sync committees from `base` if they are equal.
@@ -2489,6 +2597,7 @@ impl<E: EthSpec> BeaconState<E> {
             ForkName::Capella => BeaconStateCapella::<E>::NUM_FIELDS.next_power_of_two(),
             ForkName::Deneb => BeaconStateDeneb::<E>::NUM_FIELDS.next_power_of_two(),
             ForkName::Electra => BeaconStateElectra::<E>::NUM_FIELDS.next_power_of_two(),
+            ForkName::Fulu => BeaconStateFulu::<E>::NUM_FIELDS.next_power_of_two(),
         }
     }
 
@@ -2537,6 +2646,9 @@ impl<E: EthSpec> BeaconState<E> {
             Self::Electra(inner) => {
                 map_beacon_state_electra_tree_list_fields!(inner, |_, x| { x.apply_updates() })
             }
+            Self::Fulu(inner) => {
+                map_beacon_state_fulu_tree_list_fields!(inner, |_, x| { x.apply_updates() })
+            }
         }
         Ok(())
     }
@@ -2632,6 +2744,11 @@ impl<E: EthSpec> BeaconState<E> {
                     leaves.push(field.tree_hash_root());
                 });
             }
+            BeaconState::Fulu(state) => {
+                map_beacon_state_fulu_fields!(state, |_, field| {
+                    leaves.push(field.tree_hash_root());
+                });
+            }
         };
 
         leaves
@@ -2689,6 +2806,7 @@ impl<E: EthSpec> CompareFields for BeaconState<E> {
             (BeaconState::Capella(x), BeaconState::Capella(y)) => x.compare_fields(y),
             (BeaconState::Deneb(x), BeaconState::Deneb(y)) => x.compare_fields(y),
             (BeaconState::Electra(x), BeaconState::Electra(y)) => x.compare_fields(y),
+            (BeaconState::Fulu(x), BeaconState::Fulu(y)) => x.compare_fields(y),
             _ => panic!("compare_fields: mismatched state variants",),
         }
     }
diff --git a/consensus/types/src/beacon_state/progressive_balances_cache.rs b/consensus/types/src/beacon_state/progressive_balances_cache.rs
index fd5e51313f..8e8a1a6aa9 100644
--- a/consensus/types/src/beacon_state/progressive_balances_cache.rs
+++ b/consensus/types/src/beacon_state/progressive_balances_cache.rs
@@ -145,7 +145,7 @@ impl ProgressiveBalancesCache {
     pub fn is_initialized_at(&self, epoch: Epoch) -> bool {
         self.inner
             .as_ref()
-            .map_or(false, |inner| inner.current_epoch == epoch)
+            .is_some_and(|inner| inner.current_epoch == epoch)
     }
 
     /// When a new target attestation has been processed, we update the cached
@@ -285,12 +285,5 @@ impl ProgressiveBalancesCache {
 
 /// `ProgressiveBalancesCache` is only enabled from `Altair` as it uses Altair-specific logic.
 pub fn is_progressive_balances_enabled<E: EthSpec>(state: &BeaconState<E>) -> bool {
-    match state {
-        BeaconState::Base(_) => false,
-        BeaconState::Altair(_)
-        | BeaconState::Bellatrix(_)
-        | BeaconState::Capella(_)
-        | BeaconState::Deneb(_)
-        | BeaconState::Electra(_) => true,
-    }
+    state.fork_name_unchecked().altair_enabled()
 }
diff --git a/consensus/types/src/blob_sidecar.rs b/consensus/types/src/blob_sidecar.rs
index 5a330388cc..ff4555747c 100644
--- a/consensus/types/src/blob_sidecar.rs
+++ b/consensus/types/src/blob_sidecar.rs
@@ -1,10 +1,10 @@
 use crate::test_utils::TestRandom;
-use crate::ForkName;
 use crate::{
-    beacon_block_body::BLOB_KZG_COMMITMENTS_INDEX, BeaconBlockHeader, BeaconStateError, Blob,
-    Epoch, EthSpec, FixedVector, Hash256, SignedBeaconBlockHeader, Slot, VariableList,
+    beacon_block_body::BLOB_KZG_COMMITMENTS_INDEX, AbstractExecPayload, BeaconBlockHeader,
+    BeaconStateError, Blob, ChainSpec, Epoch, EthSpec, FixedVector, ForkName,
+    ForkVersionDeserialize, Hash256, KzgProofs, RuntimeFixedVector, RuntimeVariableList,
+    SignedBeaconBlock, SignedBeaconBlockHeader, Slot, VariableList,
 };
-use crate::{ForkVersionDeserialize, KzgProofs, SignedBeaconBlock};
 use bls::Signature;
 use derivative::Derivative;
 use kzg::{Blob as KzgBlob, Kzg, KzgCommitment, KzgProof, BYTES_PER_BLOB, BYTES_PER_FIELD_ELEMENT};
@@ -30,19 +30,6 @@ pub struct BlobIdentifier {
     pub index: u64,
 }
 
-impl BlobIdentifier {
-    pub fn get_all_blob_ids<E: EthSpec>(block_root: Hash256) -> Vec<BlobIdentifier> {
-        let mut blob_ids = Vec::with_capacity(E::max_blobs_per_block());
-        for i in 0..E::max_blobs_per_block() {
-            blob_ids.push(BlobIdentifier {
-                block_root,
-                index: i as u64,
-            });
-        }
-        blob_ids
-    }
-}
-
 impl PartialOrd for BlobIdentifier {
     fn partial_cmp(&self, other: &Self) -> Option<std::cmp::Ordering> {
         Some(self.cmp(other))
@@ -150,10 +137,10 @@ impl<E: EthSpec> BlobSidecar<E> {
         })
     }
 
-    pub fn new_with_existing_proof(
+    pub fn new_with_existing_proof<Payload: AbstractExecPayload<E>>(
         index: usize,
         blob: Blob<E>,
-        signed_block: &SignedBeaconBlock<E>,
+        signed_block: &SignedBeaconBlock<E, Payload>,
         signed_block_header: SignedBeaconBlockHeader,
         kzg_commitments_inclusion_proof: &[Hash256],
         kzg_proof: KzgProof,
@@ -291,19 +278,23 @@ impl<E: EthSpec> BlobSidecar<E> {
         blobs: BlobsList<E>,
         block: &SignedBeaconBlock<E>,
         kzg_proofs: KzgProofs<E>,
+        spec: &ChainSpec,
     ) -> Result<BlobSidecarList<E>, BlobSidecarError> {
         let mut blob_sidecars = vec![];
         for (i, (kzg_proof, blob)) in kzg_proofs.iter().zip(blobs).enumerate() {
             let blob_sidecar = BlobSidecar::new(i, blob, block, *kzg_proof)?;
             blob_sidecars.push(Arc::new(blob_sidecar));
         }
-        Ok(VariableList::from(blob_sidecars))
+        Ok(RuntimeVariableList::from_vec(
+            blob_sidecars,
+            spec.max_blobs_per_block(block.epoch()) as usize,
+        ))
     }
 }
 
-pub type BlobSidecarList<E> = VariableList<Arc<BlobSidecar<E>>, <E as EthSpec>::MaxBlobsPerBlock>;
-pub type FixedBlobSidecarList<E> =
-    FixedVector<Option<Arc<BlobSidecar<E>>>, <E as EthSpec>::MaxBlobsPerBlock>;
+pub type BlobSidecarList<E> = RuntimeVariableList<Arc<BlobSidecar<E>>>;
+/// Alias for a non length-constrained list of `BlobSidecar`s.
+pub type FixedBlobSidecarList<E> = RuntimeFixedVector<Option<Arc<BlobSidecar<E>>>>;
 pub type BlobsList<E> = VariableList<Blob<E>, <E as EthSpec>::MaxBlobCommitmentsPerBlock>;
 
 impl<E: EthSpec> ForkVersionDeserialize for BlobSidecarList<E> {
diff --git a/consensus/types/src/builder_bid.rs b/consensus/types/src/builder_bid.rs
index 9885f78474..ac53c41216 100644
--- a/consensus/types/src/builder_bid.rs
+++ b/consensus/types/src/builder_bid.rs
@@ -1,8 +1,9 @@
 use crate::beacon_block_body::KzgCommitments;
 use crate::{
     ChainSpec, EthSpec, ExecutionPayloadHeaderBellatrix, ExecutionPayloadHeaderCapella,
-    ExecutionPayloadHeaderDeneb, ExecutionPayloadHeaderElectra, ExecutionPayloadHeaderRef,
-    ExecutionPayloadHeaderRefMut, ForkName, ForkVersionDeserialize, SignedRoot, Uint256,
+    ExecutionPayloadHeaderDeneb, ExecutionPayloadHeaderElectra, ExecutionPayloadHeaderFulu,
+    ExecutionPayloadHeaderRef, ExecutionPayloadHeaderRefMut, ExecutionRequests, ForkName,
+    ForkVersionDeserialize, SignedRoot, Uint256,
 };
 use bls::PublicKeyBytes;
 use bls::Signature;
@@ -11,7 +12,7 @@ use superstruct::superstruct;
 use tree_hash_derive::TreeHash;
 
 #[superstruct(
-    variants(Bellatrix, Capella, Deneb, Electra),
+    variants(Bellatrix, Capella, Deneb, Electra, Fulu),
     variant_attributes(
         derive(PartialEq, Debug, Serialize, Deserialize, TreeHash, Clone),
         serde(bound = "E: EthSpec", deny_unknown_fields)
@@ -31,8 +32,12 @@ pub struct BuilderBid<E: EthSpec> {
     pub header: ExecutionPayloadHeaderDeneb<E>,
     #[superstruct(only(Electra), partial_getter(rename = "header_electra"))]
     pub header: ExecutionPayloadHeaderElectra<E>,
-    #[superstruct(only(Deneb, Electra))]
+    #[superstruct(only(Fulu), partial_getter(rename = "header_fulu"))]
+    pub header: ExecutionPayloadHeaderFulu<E>,
+    #[superstruct(only(Deneb, Electra, Fulu))]
     pub blob_kzg_commitments: KzgCommitments<E>,
+    #[superstruct(only(Electra, Fulu))]
+    pub execution_requests: ExecutionRequests<E>,
     #[serde(with = "serde_utils::quoted_u256")]
     pub value: Uint256,
     pub pubkey: PublicKeyBytes,
@@ -85,6 +90,7 @@ impl<E: EthSpec> ForkVersionDeserialize for BuilderBid<E> {
             ForkName::Capella => Self::Capella(serde_json::from_value(value).map_err(convert_err)?),
             ForkName::Deneb => Self::Deneb(serde_json::from_value(value).map_err(convert_err)?),
             ForkName::Electra => Self::Electra(serde_json::from_value(value).map_err(convert_err)?),
+            ForkName::Fulu => Self::Fulu(serde_json::from_value(value).map_err(convert_err)?),
             ForkName::Base | ForkName::Altair => {
                 return Err(serde::de::Error::custom(format!(
                     "BuilderBid failed to deserialize: unsupported fork '{}'",
diff --git a/consensus/types/src/chain_spec.rs b/consensus/types/src/chain_spec.rs
index 1b0ab7bbfd..f21b6e47f5 100644
--- a/consensus/types/src/chain_spec.rs
+++ b/consensus/types/src/chain_spec.rs
@@ -198,21 +198,20 @@ pub struct ChainSpec {
      */
     pub domain_inclusion_list_committee: u32,
     pub inclusion_list_committee_size: u64,
-
-    /*
-     * DAS params
-     */
-    pub eip7594_fork_epoch: Option<Epoch>,
-    pub custody_requirement: u64,
-    pub data_column_sidecar_subnet_count: u64,
-    pub number_of_columns: usize,
-    pub samples_per_slot: u64,
-
-    /*
-     * FOCIL params
-     */
     pub eip7805_fork_epoch: Option<Epoch>,
 
+    /*
+     * Fulu hard fork params
+     */
+    pub fulu_fork_version: [u8; 4],
+    /// The Fulu fork epoch is optional, with `None` representing "Fulu never happens".
+    pub fulu_fork_epoch: Option<Epoch>,
+    pub number_of_columns: u64,
+    pub number_of_custody_groups: u64,
+    pub data_column_sidecar_subnet_count: u64,
+    pub samples_per_slot: u64,
+    pub custody_requirement: u64,
+
     /*
      * Networking
      */
@@ -220,7 +219,7 @@ pub struct ChainSpec {
     pub network_id: u8,
     pub target_aggregators_per_committee: u64,
     pub gossip_max_size: u64,
-    pub max_request_blocks: u64,
+    max_request_blocks: u64,
     pub min_epochs_for_block_requests: u64,
     pub max_chunk_size: u64,
     pub ttfb_timeout: u64,
@@ -236,11 +235,19 @@ pub struct ChainSpec {
     /*
      * Networking Deneb
      */
-    pub max_request_blocks_deneb: u64,
-    pub max_request_blob_sidecars: u64,
+    max_request_blocks_deneb: u64,
+    max_request_blob_sidecars: u64,
     pub max_request_data_column_sidecars: u64,
     pub min_epochs_for_blob_sidecars_requests: u64,
-    pub blob_sidecar_subnet_count: u64,
+    blob_sidecar_subnet_count: u64,
+    max_blobs_per_block: u64,
+
+    /*
+     * Networking Electra
+     */
+    max_blobs_per_block_electra: u64,
+    blob_sidecar_subnet_count_electra: u64,
+    max_request_blob_sidecars_electra: u64,
 
     /*
      * Networking Derived
@@ -325,17 +332,20 @@ impl ChainSpec {
 
     /// Returns the name of the fork which is active at `epoch`.
     pub fn fork_name_at_epoch(&self, epoch: Epoch) -> ForkName {
-        match self.electra_fork_epoch {
-            Some(fork_epoch) if epoch >= fork_epoch => ForkName::Electra,
-            _ => match self.deneb_fork_epoch {
-                Some(fork_epoch) if epoch >= fork_epoch => ForkName::Deneb,
-                _ => match self.capella_fork_epoch {
-                    Some(fork_epoch) if epoch >= fork_epoch => ForkName::Capella,
-                    _ => match self.bellatrix_fork_epoch {
-                        Some(fork_epoch) if epoch >= fork_epoch => ForkName::Bellatrix,
-                        _ => match self.altair_fork_epoch {
-                            Some(fork_epoch) if epoch >= fork_epoch => ForkName::Altair,
-                            _ => ForkName::Base,
+        match self.fulu_fork_epoch {
+            Some(fork_epoch) if epoch >= fork_epoch => ForkName::Fulu,
+            _ => match self.electra_fork_epoch {
+                Some(fork_epoch) if epoch >= fork_epoch => ForkName::Electra,
+                _ => match self.deneb_fork_epoch {
+                    Some(fork_epoch) if epoch >= fork_epoch => ForkName::Deneb,
+                    _ => match self.capella_fork_epoch {
+                        Some(fork_epoch) if epoch >= fork_epoch => ForkName::Capella,
+                        _ => match self.bellatrix_fork_epoch {
+                            Some(fork_epoch) if epoch >= fork_epoch => ForkName::Bellatrix,
+                            _ => match self.altair_fork_epoch {
+                                Some(fork_epoch) if epoch >= fork_epoch => ForkName::Altair,
+                                _ => ForkName::Base,
+                            },
                         },
                     },
                 },
@@ -352,6 +362,7 @@ impl ChainSpec {
             ForkName::Capella => self.capella_fork_version,
             ForkName::Deneb => self.deneb_fork_version,
             ForkName::Electra => self.electra_fork_version,
+            ForkName::Fulu => self.fulu_fork_version,
         }
     }
 
@@ -364,6 +375,7 @@ impl ChainSpec {
             ForkName::Capella => self.capella_fork_epoch,
             ForkName::Deneb => self.deneb_fork_epoch,
             ForkName::Electra => self.electra_fork_epoch,
+            ForkName::Fulu => self.fulu_fork_epoch,
         }
     }
 
@@ -430,18 +442,16 @@ impl ChainSpec {
         }
     }
 
-    /// Returns true if the given epoch is greater than or equal to the `EIP7594_FORK_EPOCH`.
+    /// Returns true if the given epoch is greater than or equal to the `FULU_FORK_EPOCH`.
     pub fn is_peer_das_enabled_for_epoch(&self, block_epoch: Epoch) -> bool {
-        self.eip7594_fork_epoch.map_or(false, |eip7594_fork_epoch| {
-            block_epoch >= eip7594_fork_epoch
-        })
+        self.fulu_fork_epoch
+            .is_some_and(|fulu_fork_epoch| block_epoch >= fulu_fork_epoch)
     }
 
-    /// Returns true if `EIP7594_FORK_EPOCH` is set and is not set to `FAR_FUTURE_EPOCH`.
+    /// Returns true if `FULU_FORK_EPOCH` is set and is not set to `FAR_FUTURE_EPOCH`.
     pub fn is_peer_das_scheduled(&self) -> bool {
-        self.eip7594_fork_epoch.map_or(false, |eip7594_fork_epoch| {
-            eip7594_fork_epoch != self.far_future_epoch
-        })
+        self.fulu_fork_epoch
+            .is_some_and(|fulu_fork_epoch| fulu_fork_epoch != self.far_future_epoch)
     }
 
     /// Returns true if the given epoch is greater than or equal to the `EIP7805_FORK_EPOCH`.
@@ -632,10 +642,97 @@ impl ChainSpec {
         }
     }
 
-    pub fn data_columns_per_subnet(&self) -> usize {
+    /// Returns the highest possible value for max_request_blocks based on enabled forks.
+    ///
+    /// This is useful for upper bounds in testing.
+    pub fn max_request_blocks_upper_bound(&self) -> usize {
+        if self.deneb_fork_epoch.is_some() {
+            self.max_request_blocks_deneb as usize
+        } else {
+            self.max_request_blocks as usize
+        }
+    }
+
+    pub fn max_request_blob_sidecars(&self, fork_name: ForkName) -> usize {
+        if fork_name.electra_enabled() {
+            self.max_request_blob_sidecars_electra as usize
+        } else {
+            self.max_request_blob_sidecars as usize
+        }
+    }
+
+    /// Returns the highest possible value for max_request_blobs based on enabled forks.
+    ///
+    /// This is useful for upper bounds in testing.
+    pub fn max_request_blobs_upper_bound(&self) -> usize {
+        if self.electra_fork_epoch.is_some() {
+            self.max_request_blob_sidecars_electra as usize
+        } else {
+            self.max_request_blob_sidecars as usize
+        }
+    }
+
+    /// Return the value of `MAX_BLOBS_PER_BLOCK` appropriate for the fork at `epoch`.
+    pub fn max_blobs_per_block(&self, epoch: Epoch) -> u64 {
+        self.max_blobs_per_block_by_fork(self.fork_name_at_epoch(epoch))
+    }
+
+    /// Return the value of `MAX_BLOBS_PER_BLOCK` appropriate for `fork`.
+    pub fn max_blobs_per_block_by_fork(&self, fork_name: ForkName) -> u64 {
+        if fork_name.electra_enabled() {
+            self.max_blobs_per_block_electra
+        } else {
+            self.max_blobs_per_block
+        }
+    }
+
+    /// Returns the `BLOB_SIDECAR_SUBNET_COUNT` at the given fork_name.
+    pub fn blob_sidecar_subnet_count(&self, fork_name: ForkName) -> u64 {
+        if fork_name.electra_enabled() {
+            self.blob_sidecar_subnet_count_electra
+        } else {
+            self.blob_sidecar_subnet_count
+        }
+    }
+
+    /// Returns the highest possible value of blob sidecar subnet count based on enabled forks.
+    ///
+    /// This is useful for upper bounds for the subnet count during a given run of lighthouse.
+    pub fn blob_sidecar_subnet_count_max(&self) -> u64 {
+        if self.electra_fork_epoch.is_some() {
+            self.blob_sidecar_subnet_count_electra
+        } else {
+            self.blob_sidecar_subnet_count
+        }
+    }
+
+    /// Returns the number of data columns per custody group.
+    pub fn data_columns_per_group(&self) -> u64 {
         self.number_of_columns
-            .safe_div(self.data_column_sidecar_subnet_count as usize)
-            .expect("Subnet count must be greater than 0")
+            .safe_div(self.number_of_custody_groups)
+            .expect("Custody group count must be greater than 0")
+    }
+
+    /// Returns the number of column sidecars to sample per slot.
+    pub fn sampling_size(&self, custody_group_count: u64) -> Result<u64, String> {
+        let columns_per_custody_group = self
+            .number_of_columns
+            .safe_div(self.number_of_custody_groups)
+            .map_err(|_| "number_of_custody_groups must be greater than 0")?;
+
+        let custody_column_count = columns_per_custody_group
+            .safe_mul(custody_group_count)
+            .map_err(|_| "Computing sampling size should not overflow")?;
+
+        Ok(std::cmp::max(custody_column_count, self.samples_per_slot))
+    }
+
+    pub fn custody_group_count(&self, is_supernode: bool) -> u64 {
+        if is_supernode {
+            self.number_of_custody_groups
+        } else {
+            self.custody_requirement
+        }
     }
 
     /// Returns a `ChainSpec` compatible with the Ethereum Foundation specification.
@@ -836,21 +933,19 @@ impl ChainSpec {
              */
             domain_inclusion_list_committee: 13,
             inclusion_list_committee_size: 16,
+            eip7805_fork_epoch: None,
 
             /*
-             * DAS params
+             * Fulu hard fork params
              */
-            eip7594_fork_epoch: None,
+            fulu_fork_version: [0x06, 0x00, 0x00, 0x00],
+            fulu_fork_epoch: None,
             custody_requirement: 4,
+            number_of_custody_groups: 128,
             data_column_sidecar_subnet_count: 128,
             number_of_columns: 128,
             samples_per_slot: 8,
 
-            /*
-             * FOCIL params
-             */
-            eip7805_fork_epoch: None,
-
             /*
              * Network specific
              */
@@ -879,6 +974,7 @@ impl ChainSpec {
             max_request_data_column_sidecars: default_max_request_data_column_sidecars(),
             min_epochs_for_blob_sidecars_requests: default_min_epochs_for_blob_sidecars_requests(),
             blob_sidecar_subnet_count: default_blob_sidecar_subnet_count(),
+            max_blobs_per_block: default_max_blobs_per_block(),
 
             /*
              * Derived Deneb Specific
@@ -888,6 +984,13 @@ impl ChainSpec {
             max_blobs_by_root_request: default_max_blobs_by_root_request(),
             max_data_columns_by_root_request: default_data_columns_by_root_request(),
 
+            /*
+             * Networking Electra specific
+             */
+            max_blobs_per_block_electra: default_max_blobs_per_block_electra(),
+            blob_sidecar_subnet_count_electra: default_blob_sidecar_subnet_count_electra(),
+            max_request_blob_sidecars_electra: default_max_request_blob_sidecars_electra(),
+
             /*
              * Application specific
              */
@@ -947,7 +1050,7 @@ impl ChainSpec {
             // Electra
             electra_fork_version: [0x05, 0x00, 0x00, 0x01],
             electra_fork_epoch: None,
-            max_pending_partials_per_withdrawals_sweep: u64::checked_pow(2, 0)
+            max_pending_partials_per_withdrawals_sweep: u64::checked_pow(2, 1)
                 .expect("pow does not overflow"),
             min_per_epoch_churn_limit_electra: option_wrapper(|| {
                 u64::checked_pow(2, 6)?.checked_mul(u64::checked_pow(10, 9)?)
@@ -957,10 +1060,11 @@ impl ChainSpec {
                 u64::checked_pow(2, 7)?.checked_mul(u64::checked_pow(10, 9)?)
             })
             .expect("calculation does not overflow"),
-            // PeerDAS
-            eip7594_fork_epoch: None,
             // FOCIL
             eip7805_fork_epoch: None,
+            // Fulu
+            fulu_fork_version: [0x06, 0x00, 0x00, 0x01],
+            fulu_fork_epoch: None,
             // Other
             network_id: 2, // lighthouse testnet network id
             deposit_chain_id: 5,
@@ -1168,21 +1272,19 @@ impl ChainSpec {
              */
             domain_inclusion_list_committee: 13,
             inclusion_list_committee_size: 16,
+            eip7805_fork_epoch: None,
 
             /*
-             * DAS params
+             * Fulu hard fork params
              */
-            eip7594_fork_epoch: None,
+            fulu_fork_version: [0x06, 0x00, 0x00, 0x64],
+            fulu_fork_epoch: None,
             custody_requirement: 4,
+            number_of_custody_groups: 128,
             data_column_sidecar_subnet_count: 128,
             number_of_columns: 128,
             samples_per_slot: 8,
 
-            /*
-             * FOCIL params
-             */
-            eip7805_fork_epoch: None,
-
             /*
              * Network specific
              */
@@ -1211,6 +1313,7 @@ impl ChainSpec {
             max_request_data_column_sidecars: default_max_request_data_column_sidecars(),
             min_epochs_for_blob_sidecars_requests: 16384,
             blob_sidecar_subnet_count: default_blob_sidecar_subnet_count(),
+            max_blobs_per_block: default_max_blobs_per_block(),
 
             /*
              * Derived Deneb Specific
@@ -1220,6 +1323,13 @@ impl ChainSpec {
             max_blobs_by_root_request: default_max_blobs_by_root_request(),
             max_data_columns_by_root_request: default_data_columns_by_root_request(),
 
+            /*
+             * Networking Electra specific
+             */
+            max_blobs_per_block_electra: default_max_blobs_per_block_electra(),
+            blob_sidecar_subnet_count_electra: default_blob_sidecar_subnet_count_electra(),
+            max_request_blob_sidecars_electra: default_max_request_blob_sidecars_electra(),
+
             /*
              * Application specific
              */
@@ -1309,10 +1419,13 @@ pub struct Config {
     #[serde(deserialize_with = "deserialize_fork_epoch")]
     pub electra_fork_epoch: Option<MaybeQuoted<Epoch>>,
 
+    #[serde(default = "default_fulu_fork_version")]
+    #[serde(with = "serde_utils::bytes_4_hex")]
+    fulu_fork_version: [u8; 4],
     #[serde(default)]
     #[serde(serialize_with = "serialize_fork_epoch")]
     #[serde(deserialize_with = "deserialize_fork_epoch")]
-    pub eip7594_fork_epoch: Option<MaybeQuoted<Epoch>>,
+    pub fulu_fork_epoch: Option<MaybeQuoted<Epoch>>,
 
     #[serde(default)]
     #[serde(serialize_with = "serialize_fork_epoch")]
@@ -1409,6 +1522,9 @@ pub struct Config {
     #[serde(default = "default_blob_sidecar_subnet_count")]
     #[serde(with = "serde_utils::quoted_u64")]
     blob_sidecar_subnet_count: u64,
+    #[serde(default = "default_max_blobs_per_block")]
+    #[serde(with = "serde_utils::quoted_u64")]
+    max_blobs_per_block: u64,
 
     #[serde(default = "default_min_per_epoch_churn_limit_electra")]
     #[serde(with = "serde_utils::quoted_u64")]
@@ -1416,19 +1532,31 @@ pub struct Config {
     #[serde(default = "default_max_per_epoch_activation_exit_churn_limit")]
     #[serde(with = "serde_utils::quoted_u64")]
     max_per_epoch_activation_exit_churn_limit: u64,
+    #[serde(default = "default_max_blobs_per_block_electra")]
+    #[serde(with = "serde_utils::quoted_u64")]
+    max_blobs_per_block_electra: u64,
+    #[serde(default = "default_blob_sidecar_subnet_count_electra")]
+    #[serde(with = "serde_utils::quoted_u64")]
+    pub blob_sidecar_subnet_count_electra: u64,
+    #[serde(default = "default_max_request_blob_sidecars_electra")]
+    #[serde(with = "serde_utils::quoted_u64")]
+    max_request_blob_sidecars_electra: u64,
 
-    #[serde(default = "default_custody_requirement")]
-    #[serde(with = "serde_utils::quoted_u64")]
-    custody_requirement: u64,
-    #[serde(default = "default_data_column_sidecar_subnet_count")]
-    #[serde(with = "serde_utils::quoted_u64")]
-    data_column_sidecar_subnet_count: u64,
     #[serde(default = "default_number_of_columns")]
     #[serde(with = "serde_utils::quoted_u64")]
     number_of_columns: u64,
+    #[serde(default = "default_number_of_custody_groups")]
+    #[serde(with = "serde_utils::quoted_u64")]
+    number_of_custody_groups: u64,
+    #[serde(default = "default_data_column_sidecar_subnet_count")]
+    #[serde(with = "serde_utils::quoted_u64")]
+    data_column_sidecar_subnet_count: u64,
     #[serde(default = "default_samples_per_slot")]
     #[serde(with = "serde_utils::quoted_u64")]
     samples_per_slot: u64,
+    #[serde(default = "default_custody_requirement")]
+    #[serde(with = "serde_utils::quoted_u64")]
+    custody_requirement: u64,
 }
 
 fn default_bellatrix_fork_version() -> [u8; 4] {
@@ -1451,6 +1579,11 @@ fn default_electra_fork_version() -> [u8; 4] {
     [0xff, 0xff, 0xff, 0xff]
 }
 
+fn default_fulu_fork_version() -> [u8; 4] {
+    // This value shouldn't be used.
+    [0xff, 0xff, 0xff, 0xff]
+}
+
 /// Placeholder value: 2^256-2^10 (115792089237316195423570985008687907853269984665640564039457584007913129638912).
 ///
 /// Taken from https://github.com/ethereum/consensus-specs/blob/d5e4828aecafaf1c57ef67a5f23c4ae7b08c5137/configs/mainnet.yaml#L15-L16
@@ -1539,6 +1672,20 @@ const fn default_blob_sidecar_subnet_count() -> u64 {
     6
 }
 
+/// Its important to keep this consistent with the deneb preset value for
+/// `MAX_BLOBS_PER_BLOCK` else we might run into consensus issues.
+const fn default_max_blobs_per_block() -> u64 {
+    6
+}
+
+const fn default_blob_sidecar_subnet_count_electra() -> u64 {
+    9
+}
+
+const fn default_max_request_blob_sidecars_electra() -> u64 {
+    1152
+}
+
 const fn default_min_per_epoch_churn_limit_electra() -> u64 {
     128_000_000_000
 }
@@ -1547,6 +1694,10 @@ const fn default_max_per_epoch_activation_exit_churn_limit() -> u64 {
     256_000_000_000
 }
 
+const fn default_max_blobs_per_block_electra() -> u64 {
+    9
+}
+
 const fn default_attestation_propagation_slot_range() -> u64 {
     32
 }
@@ -1567,6 +1718,10 @@ const fn default_number_of_columns() -> u64 {
     128
 }
 
+const fn default_number_of_custody_groups() -> u64 {
+    128
+}
+
 const fn default_samples_per_slot() -> u64 {
     8
 }
@@ -1714,8 +1869,9 @@ impl Config {
                 .electra_fork_epoch
                 .map(|epoch| MaybeQuoted { value: epoch }),
 
-            eip7594_fork_epoch: spec
-                .eip7594_fork_epoch
+            fulu_fork_version: spec.fulu_fork_version,
+            fulu_fork_epoch: spec
+                .fulu_fork_epoch
                 .map(|epoch| MaybeQuoted { value: epoch }),
 
             eip7805_fork_epoch: spec
@@ -1760,15 +1916,20 @@ impl Config {
             max_request_data_column_sidecars: spec.max_request_data_column_sidecars,
             min_epochs_for_blob_sidecars_requests: spec.min_epochs_for_blob_sidecars_requests,
             blob_sidecar_subnet_count: spec.blob_sidecar_subnet_count,
+            max_blobs_per_block: spec.max_blobs_per_block,
 
             min_per_epoch_churn_limit_electra: spec.min_per_epoch_churn_limit_electra,
             max_per_epoch_activation_exit_churn_limit: spec
                 .max_per_epoch_activation_exit_churn_limit,
+            max_blobs_per_block_electra: spec.max_blobs_per_block_electra,
+            blob_sidecar_subnet_count_electra: spec.blob_sidecar_subnet_count_electra,
+            max_request_blob_sidecars_electra: spec.max_request_blob_sidecars_electra,
 
-            custody_requirement: spec.custody_requirement,
+            number_of_columns: spec.number_of_columns,
+            number_of_custody_groups: spec.number_of_custody_groups,
             data_column_sidecar_subnet_count: spec.data_column_sidecar_subnet_count,
-            number_of_columns: spec.number_of_columns as u64,
             samples_per_slot: spec.samples_per_slot,
+            custody_requirement: spec.custody_requirement,
         }
     }
 
@@ -1801,8 +1962,9 @@ impl Config {
             deneb_fork_version,
             electra_fork_epoch,
             electra_fork_version,
-            eip7594_fork_epoch,
             eip7805_fork_epoch,
+            fulu_fork_epoch,
+            fulu_fork_version,
             seconds_per_slot,
             seconds_per_eth1_block,
             min_validator_withdrawability_delay,
@@ -1836,13 +1998,18 @@ impl Config {
             max_request_data_column_sidecars,
             min_epochs_for_blob_sidecars_requests,
             blob_sidecar_subnet_count,
+            max_blobs_per_block,
 
             min_per_epoch_churn_limit_electra,
             max_per_epoch_activation_exit_churn_limit,
-            custody_requirement,
-            data_column_sidecar_subnet_count,
+            max_blobs_per_block_electra,
+            blob_sidecar_subnet_count_electra,
+            max_request_blob_sidecars_electra,
             number_of_columns,
+            number_of_custody_groups,
+            data_column_sidecar_subnet_count,
             samples_per_slot,
+            custody_requirement,
         } = self;
 
         if preset_base != E::spec_name().to_string().as_str() {
@@ -1865,8 +2032,9 @@ impl Config {
             deneb_fork_version,
             electra_fork_epoch: electra_fork_epoch.map(|q| q.value),
             electra_fork_version,
-            eip7594_fork_epoch: eip7594_fork_epoch.map(|q| q.value),
             eip7805_fork_epoch: eip7805_fork_epoch.map(|q| q.value),
+            fulu_fork_epoch: fulu_fork_epoch.map(|q| q.value),
+            fulu_fork_version,
             seconds_per_slot,
             seconds_per_eth1_block,
             min_validator_withdrawability_delay,
@@ -1903,9 +2071,13 @@ impl Config {
             max_request_data_column_sidecars,
             min_epochs_for_blob_sidecars_requests,
             blob_sidecar_subnet_count,
+            max_blobs_per_block,
 
             min_per_epoch_churn_limit_electra,
             max_per_epoch_activation_exit_churn_limit,
+            max_blobs_per_block_electra,
+            max_request_blob_sidecars_electra,
+            blob_sidecar_subnet_count_electra,
 
             // We need to re-derive any values that might have changed in the config.
             max_blocks_by_root_request: max_blocks_by_root_request_common(max_request_blocks),
@@ -1917,10 +2089,11 @@ impl Config {
                 max_request_data_column_sidecars,
             ),
 
-            custody_requirement,
+            number_of_columns,
+            number_of_custody_groups,
             data_column_sidecar_subnet_count,
-            number_of_columns: number_of_columns as usize,
             samples_per_slot,
+            custody_requirement,
 
             ..chain_spec.clone()
         })
diff --git a/consensus/types/src/config_and_preset.rs b/consensus/types/src/config_and_preset.rs
index c80d678b2a..235bf20238 100644
--- a/consensus/types/src/config_and_preset.rs
+++ b/consensus/types/src/config_and_preset.rs
@@ -1,6 +1,6 @@
 use crate::{
     consts::altair, consts::deneb, AltairPreset, BasePreset, BellatrixPreset, CapellaPreset,
-    ChainSpec, Config, DenebPreset, ElectraPreset, EthSpec, ForkName,
+    ChainSpec, Config, DenebPreset, ElectraPreset, EthSpec, ForkName, FuluPreset,
 };
 use maplit::hashmap;
 use serde::{Deserialize, Serialize};
@@ -12,7 +12,7 @@ use superstruct::superstruct;
 ///
 /// Mostly useful for the API.
 #[superstruct(
-    variants(Capella, Deneb, Electra),
+    variants(Deneb, Electra, Fulu),
     variant_attributes(derive(Serialize, Deserialize, Debug, PartialEq, Clone))
 )]
 #[derive(Serialize, Deserialize, Debug, PartialEq, Clone)]
@@ -29,12 +29,14 @@ pub struct ConfigAndPreset {
     pub bellatrix_preset: BellatrixPreset,
     #[serde(flatten)]
     pub capella_preset: CapellaPreset,
-    #[superstruct(only(Deneb, Electra))]
     #[serde(flatten)]
     pub deneb_preset: DenebPreset,
-    #[superstruct(only(Electra))]
+    #[superstruct(only(Electra, Fulu))]
     #[serde(flatten)]
     pub electra_preset: ElectraPreset,
+    #[superstruct(only(Fulu))]
+    #[serde(flatten)]
+    pub fulu_preset: FuluPreset,
     /// The `extra_fields` map allows us to gracefully decode fields intended for future hard forks.
     #[serde(flatten)]
     pub extra_fields: HashMap<String, Value>,
@@ -48,13 +50,31 @@ impl ConfigAndPreset {
         let altair_preset = AltairPreset::from_chain_spec::<E>(spec);
         let bellatrix_preset = BellatrixPreset::from_chain_spec::<E>(spec);
         let capella_preset = CapellaPreset::from_chain_spec::<E>(spec);
+        let deneb_preset = DenebPreset::from_chain_spec::<E>(spec);
         let extra_fields = get_extra_fields(spec);
 
-        if spec.electra_fork_epoch.is_some()
+        if spec.fulu_fork_epoch.is_some()
+            || fork_name.is_none()
+            || fork_name == Some(ForkName::Fulu)
+        {
+            let electra_preset = ElectraPreset::from_chain_spec::<E>(spec);
+            let fulu_preset = FuluPreset::from_chain_spec::<E>(spec);
+
+            ConfigAndPreset::Fulu(ConfigAndPresetFulu {
+                config,
+                base_preset,
+                altair_preset,
+                bellatrix_preset,
+                capella_preset,
+                deneb_preset,
+                electra_preset,
+                fulu_preset,
+                extra_fields,
+            })
+        } else if spec.electra_fork_epoch.is_some()
             || fork_name.is_none()
             || fork_name == Some(ForkName::Electra)
         {
-            let deneb_preset = DenebPreset::from_chain_spec::<E>(spec);
             let electra_preset = ElectraPreset::from_chain_spec::<E>(spec);
 
             ConfigAndPreset::Electra(ConfigAndPresetElectra {
@@ -67,11 +87,7 @@ impl ConfigAndPreset {
                 electra_preset,
                 extra_fields,
             })
-        } else if spec.deneb_fork_epoch.is_some()
-            || fork_name.is_none()
-            || fork_name == Some(ForkName::Deneb)
-        {
-            let deneb_preset = DenebPreset::from_chain_spec::<E>(spec);
+        } else {
             ConfigAndPreset::Deneb(ConfigAndPresetDeneb {
                 config,
                 base_preset,
@@ -81,15 +97,6 @@ impl ConfigAndPreset {
                 deneb_preset,
                 extra_fields,
             })
-        } else {
-            ConfigAndPreset::Capella(ConfigAndPresetCapella {
-                config,
-                base_preset,
-                altair_preset,
-                bellatrix_preset,
-                capella_preset,
-                extra_fields,
-            })
         }
     }
 }
@@ -164,8 +171,8 @@ mod test {
             .write(false)
             .open(tmp_file.as_ref())
             .expect("error while opening the file");
-        let from: ConfigAndPresetElectra =
+        let from: ConfigAndPresetFulu =
             serde_yaml::from_reader(reader).expect("error while deserializing");
-        assert_eq!(ConfigAndPreset::Electra(from), yamlconfig);
+        assert_eq!(ConfigAndPreset::Fulu(from), yamlconfig);
     }
 }
diff --git a/consensus/types/src/data_column_custody_group.rs b/consensus/types/src/data_column_custody_group.rs
new file mode 100644
index 0000000000..bb204c34a2
--- /dev/null
+++ b/consensus/types/src/data_column_custody_group.rs
@@ -0,0 +1,142 @@
+use crate::{ChainSpec, ColumnIndex, DataColumnSubnetId};
+use alloy_primitives::U256;
+use itertools::Itertools;
+use maplit::hashset;
+use safe_arith::{ArithError, SafeArith};
+use std::collections::HashSet;
+
+pub type CustodyIndex = u64;
+
+#[derive(Debug)]
+pub enum DataColumnCustodyGroupError {
+    InvalidCustodyGroup(CustodyIndex),
+    InvalidCustodyGroupCount(u64),
+    ArithError(ArithError),
+}
+
+/// The `get_custody_groups` function is used to determine the custody groups that a node is
+/// assigned to.
+///
+/// spec: https://github.com/ethereum/consensus-specs/blob/8e0d0d48e81d6c7c5a8253ab61340f5ea5bac66a/specs/fulu/das-core.md#get_custody_groups
+pub fn get_custody_groups(
+    raw_node_id: [u8; 32],
+    custody_group_count: u64,
+    spec: &ChainSpec,
+) -> Result<HashSet<CustodyIndex>, DataColumnCustodyGroupError> {
+    if custody_group_count > spec.number_of_custody_groups {
+        return Err(DataColumnCustodyGroupError::InvalidCustodyGroupCount(
+            custody_group_count,
+        ));
+    }
+
+    let mut custody_groups: HashSet<u64> = hashset![];
+    let mut current_id = U256::from_be_slice(&raw_node_id);
+    while custody_groups.len() < custody_group_count as usize {
+        let mut node_id_bytes = [0u8; 32];
+        node_id_bytes.copy_from_slice(current_id.as_le_slice());
+        let hash = ethereum_hashing::hash_fixed(&node_id_bytes);
+        let hash_prefix: [u8; 8] = hash[0..8]
+            .try_into()
+            .expect("hash_fixed produces a 32 byte array");
+        let hash_prefix_u64 = u64::from_le_bytes(hash_prefix);
+        let custody_group = hash_prefix_u64
+            .safe_rem(spec.number_of_custody_groups)
+            .expect("spec.number_of_custody_groups must not be zero");
+        custody_groups.insert(custody_group);
+
+        current_id = current_id.wrapping_add(U256::from(1u64));
+    }
+
+    Ok(custody_groups)
+}
+
+/// Returns the columns that are associated with a given custody group.
+///
+/// spec: https://github.com/ethereum/consensus-specs/blob/8e0d0d48e81d6c7c5a8253ab61340f5ea5bac66a/specs/fulu/das-core.md#compute_columns_for_custody_group
+pub fn compute_columns_for_custody_group(
+    custody_group: CustodyIndex,
+    spec: &ChainSpec,
+) -> Result<impl Iterator<Item = ColumnIndex>, DataColumnCustodyGroupError> {
+    let number_of_custody_groups = spec.number_of_custody_groups;
+    if custody_group >= number_of_custody_groups {
+        return Err(DataColumnCustodyGroupError::InvalidCustodyGroup(
+            custody_group,
+        ));
+    }
+
+    let mut columns = Vec::new();
+    for i in 0..spec.data_columns_per_group() {
+        let column = number_of_custody_groups
+            .safe_mul(i)
+            .and_then(|v| v.safe_add(custody_group))
+            .map_err(DataColumnCustodyGroupError::ArithError)?;
+        columns.push(column);
+    }
+
+    Ok(columns.into_iter())
+}
+
+pub fn compute_subnets_for_node(
+    raw_node_id: [u8; 32],
+    custody_group_count: u64,
+    spec: &ChainSpec,
+) -> Result<HashSet<DataColumnSubnetId>, DataColumnCustodyGroupError> {
+    let custody_groups = get_custody_groups(raw_node_id, custody_group_count, spec)?;
+    let mut subnets = HashSet::new();
+
+    for custody_group in custody_groups {
+        let custody_group_subnets = compute_subnets_from_custody_group(custody_group, spec)?;
+        subnets.extend(custody_group_subnets);
+    }
+
+    Ok(subnets)
+}
+
+/// Returns the subnets that are associated with a given custody group.
+pub fn compute_subnets_from_custody_group(
+    custody_group: CustodyIndex,
+    spec: &ChainSpec,
+) -> Result<impl Iterator<Item = DataColumnSubnetId> + '_, DataColumnCustodyGroupError> {
+    let result = compute_columns_for_custody_group(custody_group, spec)?
+        .map(|column_index| DataColumnSubnetId::from_column_index(column_index, spec))
+        .unique();
+    Ok(result)
+}
+
+#[cfg(test)]
+mod test {
+    use super::*;
+
+    #[test]
+    fn test_compute_columns_for_custody_group() {
+        let mut spec = ChainSpec::mainnet();
+        spec.number_of_custody_groups = 64;
+        spec.number_of_columns = 128;
+        let columns_per_custody_group = spec.number_of_columns / spec.number_of_custody_groups;
+
+        for custody_group in 0..spec.number_of_custody_groups {
+            let columns = compute_columns_for_custody_group(custody_group, &spec)
+                .unwrap()
+                .collect::<Vec<_>>();
+            assert_eq!(columns.len(), columns_per_custody_group as usize);
+        }
+    }
+
+    #[test]
+    fn test_compute_subnets_from_custody_group() {
+        let mut spec = ChainSpec::mainnet();
+        spec.number_of_custody_groups = 64;
+        spec.number_of_columns = 256;
+        spec.data_column_sidecar_subnet_count = 128;
+
+        let subnets_per_custody_group =
+            spec.data_column_sidecar_subnet_count / spec.number_of_custody_groups;
+
+        for custody_group in 0..spec.number_of_custody_groups {
+            let subnets = compute_subnets_from_custody_group(custody_group, &spec)
+                .unwrap()
+                .collect::<Vec<_>>();
+            assert_eq!(subnets.len(), subnets_per_custody_group as usize);
+        }
+    }
+}
diff --git a/consensus/types/src/data_column_sidecar.rs b/consensus/types/src/data_column_sidecar.rs
index 57251e319a..90a914dfae 100644
--- a/consensus/types/src/data_column_sidecar.rs
+++ b/consensus/types/src/data_column_sidecar.rs
@@ -1,7 +1,7 @@
 use crate::beacon_block_body::{KzgCommitments, BLOB_KZG_COMMITMENTS_INDEX};
 use crate::test_utils::TestRandom;
 use crate::BeaconStateError;
-use crate::{BeaconBlockHeader, EthSpec, Hash256, KzgProofs, SignedBeaconBlockHeader, Slot};
+use crate::{BeaconBlockHeader, Epoch, EthSpec, Hash256, KzgProofs, SignedBeaconBlockHeader, Slot};
 use bls::Signature;
 use derivative::Derivative;
 use kzg::Error as KzgError;
@@ -11,7 +11,6 @@ use safe_arith::ArithError;
 use serde::{Deserialize, Serialize};
 use ssz::Encode;
 use ssz_derive::{Decode, Encode};
-use ssz_types::typenum::Unsigned;
 use ssz_types::Error as SszError;
 use ssz_types::{FixedVector, VariableList};
 use std::hash::Hash;
@@ -68,6 +67,10 @@ impl<E: EthSpec> DataColumnSidecar<E> {
         self.signed_block_header.message.slot
     }
 
+    pub fn epoch(&self) -> Epoch {
+        self.slot().epoch(E::slots_per_epoch())
+    }
+
     pub fn block_root(&self) -> Hash256 {
         self.signed_block_header.message.tree_hash_root()
     }
@@ -110,18 +113,16 @@ impl<E: EthSpec> DataColumnSidecar<E> {
         .len()
     }
 
-    pub fn max_size() -> usize {
+    pub fn max_size(max_blobs_per_block: usize) -> usize {
         Self {
             index: 0,
-            column: VariableList::new(vec![Cell::<E>::default(); E::MaxBlobsPerBlock::to_usize()])
-                .unwrap(),
+            column: VariableList::new(vec![Cell::<E>::default(); max_blobs_per_block]).unwrap(),
             kzg_commitments: VariableList::new(vec![
                 KzgCommitment::empty_for_testing();
-                E::MaxBlobsPerBlock::to_usize()
+                max_blobs_per_block
             ])
             .unwrap(),
-            kzg_proofs: VariableList::new(vec![KzgProof::empty(); E::MaxBlobsPerBlock::to_usize()])
-                .unwrap(),
+            kzg_proofs: VariableList::new(vec![KzgProof::empty(); max_blobs_per_block]).unwrap(),
             signed_block_header: SignedBeaconBlockHeader {
                 message: BeaconBlockHeader::empty(),
                 signature: Signature::empty(),
@@ -132,20 +133,6 @@ impl<E: EthSpec> DataColumnSidecar<E> {
         .len()
     }
 
-    pub fn empty() -> Self {
-        Self {
-            index: 0,
-            column: DataColumn::<E>::default(),
-            kzg_commitments: VariableList::default(),
-            kzg_proofs: VariableList::default(),
-            signed_block_header: SignedBeaconBlockHeader {
-                message: BeaconBlockHeader::empty(),
-                signature: Signature::empty(),
-            },
-            kzg_commitments_inclusion_proof: Default::default(),
-        }
-    }
-
     pub fn id(&self) -> DataColumnIdentifier {
         DataColumnIdentifier {
             block_root: self.block_root(),
diff --git a/consensus/types/src/data_column_subnet_id.rs b/consensus/types/src/data_column_subnet_id.rs
index df61d711c1..5b3eef24cc 100644
--- a/consensus/types/src/data_column_subnet_id.rs
+++ b/consensus/types/src/data_column_subnet_id.rs
@@ -1,11 +1,8 @@
 //! Identifies each data column subnet by an integer identifier.
 use crate::data_column_sidecar::ColumnIndex;
-use crate::{ChainSpec, EthSpec};
-use alloy_primitives::U256;
-use itertools::Itertools;
+use crate::ChainSpec;
 use safe_arith::{ArithError, SafeArith};
 use serde::{Deserialize, Serialize};
-use std::collections::HashSet;
 use std::fmt::{self, Display};
 use std::ops::{Deref, DerefMut};
 
@@ -18,76 +15,14 @@ impl DataColumnSubnetId {
         id.into()
     }
 
-    pub fn from_column_index<E: EthSpec>(column_index: usize, spec: &ChainSpec) -> Self {
-        (column_index
-            .safe_rem(spec.data_column_sidecar_subnet_count as usize)
+    pub fn from_column_index(column_index: ColumnIndex, spec: &ChainSpec) -> Self {
+        column_index
+            .safe_rem(spec.data_column_sidecar_subnet_count)
             .expect(
                 "data_column_sidecar_subnet_count should never be zero if this function is called",
-            ) as u64)
+            )
             .into()
     }
-
-    #[allow(clippy::arithmetic_side_effects)]
-    pub fn columns<E: EthSpec>(&self, spec: &ChainSpec) -> impl Iterator<Item = ColumnIndex> {
-        let subnet = self.0;
-        let data_column_sidecar_subnet = spec.data_column_sidecar_subnet_count;
-        let columns_per_subnet = spec.data_columns_per_subnet() as u64;
-        (0..columns_per_subnet).map(move |i| data_column_sidecar_subnet * i + subnet)
-    }
-
-    /// Compute required subnets to subscribe to given the node id.
-    #[allow(clippy::arithmetic_side_effects)]
-    pub fn compute_custody_subnets<E: EthSpec>(
-        raw_node_id: [u8; 32],
-        custody_subnet_count: u64,
-        spec: &ChainSpec,
-    ) -> Result<impl Iterator<Item = DataColumnSubnetId>, Error> {
-        if custody_subnet_count > spec.data_column_sidecar_subnet_count {
-            return Err(Error::InvalidCustodySubnetCount(custody_subnet_count));
-        }
-
-        let mut subnets: HashSet<u64> = HashSet::new();
-        let mut current_id = U256::from_be_slice(&raw_node_id);
-        while (subnets.len() as u64) < custody_subnet_count {
-            let mut node_id_bytes = [0u8; 32];
-            node_id_bytes.copy_from_slice(current_id.as_le_slice());
-            let hash = ethereum_hashing::hash_fixed(&node_id_bytes);
-            let hash_prefix: [u8; 8] = hash[0..8]
-                .try_into()
-                .expect("hash_fixed produces a 32 byte array");
-            let hash_prefix_u64 = u64::from_le_bytes(hash_prefix);
-            let subnet = hash_prefix_u64 % spec.data_column_sidecar_subnet_count;
-
-            if !subnets.contains(&subnet) {
-                subnets.insert(subnet);
-            }
-
-            if current_id == U256::MAX {
-                current_id = U256::ZERO
-            }
-            current_id += U256::from(1u64)
-        }
-        Ok(subnets.into_iter().map(DataColumnSubnetId::new))
-    }
-
-    /// Compute the custody subnets for a given node id with the default `custody_requirement`.
-    /// This operation should be infallable, and empty iterator is returned if it fails unexpectedly.
-    pub fn compute_custody_requirement_subnets<E: EthSpec>(
-        node_id: [u8; 32],
-        spec: &ChainSpec,
-    ) -> impl Iterator<Item = DataColumnSubnetId> {
-        Self::compute_custody_subnets::<E>(node_id, spec.custody_requirement, spec)
-            .expect("should compute default custody subnets")
-    }
-
-    pub fn compute_custody_columns<E: EthSpec>(
-        raw_node_id: [u8; 32],
-        custody_subnet_count: u64,
-        spec: &ChainSpec,
-    ) -> Result<impl Iterator<Item = ColumnIndex>, Error> {
-        Self::compute_custody_subnets::<E>(raw_node_id, custody_subnet_count, spec)
-            .map(|subnet| subnet.flat_map(|subnet| subnet.columns::<E>(spec)).sorted())
-    }
 }
 
 impl Display for DataColumnSubnetId {
@@ -139,88 +74,3 @@ impl From<ArithError> for Error {
         Error::ArithError(e)
     }
 }
-
-#[cfg(test)]
-mod test {
-    use crate::data_column_subnet_id::DataColumnSubnetId;
-    use crate::MainnetEthSpec;
-    use crate::Uint256;
-    use crate::{EthSpec, GnosisEthSpec, MinimalEthSpec};
-
-    type E = MainnetEthSpec;
-
-    #[test]
-    fn test_compute_subnets_for_data_column() {
-        let spec = E::default_spec();
-        let node_ids = [
-            "0",
-            "88752428858350697756262172400162263450541348766581994718383409852729519486397",
-            "18732750322395381632951253735273868184515463718109267674920115648614659369468",
-            "27726842142488109545414954493849224833670205008410190955613662332153332462900",
-            "39755236029158558527862903296867805548949739810920318269566095185775868999998",
-            "31899136003441886988955119620035330314647133604576220223892254902004850516297",
-            "58579998103852084482416614330746509727562027284701078483890722833654510444626",
-            "28248042035542126088870192155378394518950310811868093527036637864276176517397",
-            "60930578857433095740782970114409273483106482059893286066493409689627770333527",
-            "103822458477361691467064888613019442068586830412598673713899771287914656699997",
-        ]
-        .into_iter()
-        .map(|v| Uint256::from_str_radix(v, 10).unwrap().to_be_bytes::<32>())
-        .collect::<Vec<_>>();
-
-        let custody_requirement = 4;
-        for node_id in node_ids {
-            let computed_subnets = DataColumnSubnetId::compute_custody_subnets::<E>(
-                node_id,
-                custody_requirement,
-                &spec,
-            )
-            .unwrap();
-            let computed_subnets: Vec<_> = computed_subnets.collect();
-
-            // the number of subnets is equal to the custody requirement
-            assert_eq!(computed_subnets.len() as u64, custody_requirement);
-
-            let subnet_count = spec.data_column_sidecar_subnet_count;
-            for subnet in computed_subnets {
-                let columns: Vec<_> = subnet.columns::<E>(&spec).collect();
-                // the number of columns is equal to the specified number of columns per subnet
-                assert_eq!(columns.len(), spec.data_columns_per_subnet());
-
-                for pair in columns.windows(2) {
-                    // each successive column index is offset by the number of subnets
-                    assert_eq!(pair[1] - pair[0], subnet_count);
-                }
-            }
-        }
-    }
-
-    #[test]
-    fn test_compute_custody_requirement_subnets_never_panics() {
-        let node_id = [1u8; 32];
-        test_compute_custody_requirement_subnets_with_spec::<MainnetEthSpec>(node_id);
-        test_compute_custody_requirement_subnets_with_spec::<MinimalEthSpec>(node_id);
-        test_compute_custody_requirement_subnets_with_spec::<GnosisEthSpec>(node_id);
-    }
-
-    fn test_compute_custody_requirement_subnets_with_spec<E: EthSpec>(node_id: [u8; 32]) {
-        let _ = DataColumnSubnetId::compute_custody_requirement_subnets::<E>(
-            node_id,
-            &E::default_spec(),
-        );
-    }
-
-    #[test]
-    fn test_columns_subnet_conversion() {
-        let spec = E::default_spec();
-        for subnet in 0..spec.data_column_sidecar_subnet_count {
-            let subnet_id = DataColumnSubnetId::new(subnet);
-            for column_index in subnet_id.columns::<E>(&spec) {
-                assert_eq!(
-                    subnet_id,
-                    DataColumnSubnetId::from_column_index::<E>(column_index as usize, &spec)
-                );
-            }
-        }
-    }
-}
diff --git a/consensus/types/src/deposit_tree_snapshot.rs b/consensus/types/src/deposit_tree_snapshot.rs
index df1064daba..2f9df8758b 100644
--- a/consensus/types/src/deposit_tree_snapshot.rs
+++ b/consensus/types/src/deposit_tree_snapshot.rs
@@ -72,8 +72,7 @@ impl DepositTreeSnapshot {
         Some(Hash256::from_slice(&deposit_root))
     }
     pub fn is_valid(&self) -> bool {
-        self.calculate_root()
-            .map_or(false, |calculated| self.deposit_root == calculated)
+        self.calculate_root() == Some(self.deposit_root)
     }
 }
 
diff --git a/consensus/types/src/eth_spec.rs b/consensus/types/src/eth_spec.rs
index 9c7245f4c3..1c28acccaf 100644
--- a/consensus/types/src/eth_spec.rs
+++ b/consensus/types/src/eth_spec.rs
@@ -3,11 +3,10 @@ use crate::*;
 use safe_arith::SafeArith;
 use serde::{Deserialize, Serialize};
 use ssz_types::typenum::{
-    bit::B0, UInt, U0, U1, U1024, U1048576, U1073741824, U1099511627776, U128, U131072, U134217728,
-    U16, U16777216, U2, U2048, U256, U262144, U32, U4, U4096, U512, U6, U625, U64, U65536, U8,
-    U8192,
+    bit::B0, UInt, U0, U1, U10, U1024, U1048576, U1073741824, U1099511627776, U128, U131072,
+    U134217728, U16, U16777216, U17, U2, U2048, U256, U262144, U32, U4, U4096, U512, U625, U64,
+    U65536, U8, U8192,
 };
-use ssz_types::typenum::{U17, U9};
 use std::fmt::{self, Debug};
 use std::str::FromStr;
 
@@ -109,7 +108,6 @@ pub trait EthSpec:
     /*
      * New in Deneb
      */
-    type MaxBlobsPerBlock: Unsigned + Clone + Sync + Send + Debug + PartialEq + Unpin;
     type MaxBlobCommitmentsPerBlock: Unsigned + Clone + Sync + Send + Debug + PartialEq + Unpin;
     type FieldElementsPerBlob: Unsigned + Clone + Sync + Send + Debug + PartialEq;
     type BytesPerFieldElement: Unsigned + Clone + Sync + Send + Debug + PartialEq;
@@ -287,11 +285,6 @@ pub trait EthSpec:
         Self::MaxWithdrawalsPerPayload::to_usize()
     }
 
-    /// Returns the `MAX_BLOBS_PER_BLOCK` constant for this specification.
-    fn max_blobs_per_block() -> usize {
-        Self::MaxBlobsPerBlock::to_usize()
-    }
-
     /// Returns the `MAX_BLOB_COMMITMENTS_PER_BLOCK` constant for this specification.
     fn max_blob_commitments_per_block() -> usize {
         Self::MaxBlobCommitmentsPerBlock::to_usize()
@@ -437,7 +430,6 @@ impl EthSpec for MainnetEthSpec {
     type GasLimitDenominator = U1024;
     type MinGasLimit = U5000;
     type MaxExtraDataBytes = U32;
-    type MaxBlobsPerBlock = U6;
     type MaxBlobCommitmentsPerBlock = U4096;
     type BytesPerFieldElement = U32;
     type FieldElementsPerBlob = U4096;
@@ -455,7 +447,7 @@ impl EthSpec for MainnetEthSpec {
     type PendingDepositsLimit = U134217728;
     type PendingPartialWithdrawalsLimit = U134217728;
     type PendingConsolidationsLimit = U262144;
-    type MaxConsolidationRequestsPerPayload = U1;
+    type MaxConsolidationRequestsPerPayload = U2;
     type MaxDepositRequestsPerPayload = U8192;
     type MaxAttesterSlashingsElectra = U1;
     type MaxAttestationsElectra = U8;
@@ -492,8 +484,8 @@ impl EthSpec for MinimalEthSpec {
     type MaxWithdrawalsPerPayload = U4;
     type FieldElementsPerBlob = U4096;
     type BytesPerBlob = U131072;
-    type MaxBlobCommitmentsPerBlock = U16;
-    type KzgCommitmentInclusionProofDepth = U9;
+    type MaxBlobCommitmentsPerBlock = U32;
+    type KzgCommitmentInclusionProofDepth = U10;
     type PendingPartialWithdrawalsLimit = U64;
     type PendingConsolidationsLimit = U64;
     type MaxDepositRequestsPerPayload = U4;
@@ -523,7 +515,6 @@ impl EthSpec for MinimalEthSpec {
         MinGasLimit,
         MaxExtraDataBytes,
         MaxBlsToExecutionChanges,
-        MaxBlobsPerBlock,
         BytesPerFieldElement,
         PendingDepositsLimit,
         MaxPendingDepositsPerEpoch,
@@ -579,7 +570,6 @@ impl EthSpec for GnosisEthSpec {
     type SlotsPerEth1VotingPeriod = U1024; // 64 epochs * 16 slots per epoch
     type MaxBlsToExecutionChanges = U16;
     type MaxWithdrawalsPerPayload = U8;
-    type MaxBlobsPerBlock = U6;
     type MaxBlobCommitmentsPerBlock = U4096;
     type FieldElementsPerBlob = U4096;
     type BytesPerFieldElement = U32;
@@ -588,7 +578,7 @@ impl EthSpec for GnosisEthSpec {
     type PendingDepositsLimit = U134217728;
     type PendingPartialWithdrawalsLimit = U134217728;
     type PendingConsolidationsLimit = U262144;
-    type MaxConsolidationRequestsPerPayload = U1;
+    type MaxConsolidationRequestsPerPayload = U2;
     type MaxDepositRequestsPerPayload = U8192;
     type MaxAttesterSlashingsElectra = U1;
     type MaxAttestationsElectra = U8;
diff --git a/consensus/types/src/execution_payload.rs b/consensus/types/src/execution_payload.rs
index 9f16b676a6..2df66343af 100644
--- a/consensus/types/src/execution_payload.rs
+++ b/consensus/types/src/execution_payload.rs
@@ -15,7 +15,7 @@ pub type Transactions<E> = VariableList<
 pub type Withdrawals<E> = VariableList<Withdrawal, <E as EthSpec>::MaxWithdrawalsPerPayload>;
 
 #[superstruct(
-    variants(Bellatrix, Capella, Deneb, Electra),
+    variants(Bellatrix, Capella, Deneb, Electra, Fulu),
     variant_attributes(
         derive(
             Default,
@@ -82,12 +82,12 @@ pub struct ExecutionPayload<E: EthSpec> {
     pub block_hash: ExecutionBlockHash,
     #[serde(with = "ssz_types::serde_utils::list_of_hex_var_list")]
     pub transactions: Transactions<E>,
-    #[superstruct(only(Capella, Deneb, Electra))]
+    #[superstruct(only(Capella, Deneb, Electra, Fulu))]
     pub withdrawals: Withdrawals<E>,
-    #[superstruct(only(Deneb, Electra), partial_getter(copy))]
+    #[superstruct(only(Deneb, Electra, Fulu), partial_getter(copy))]
     #[serde(with = "serde_utils::quoted_u64")]
     pub blob_gas_used: u64,
-    #[superstruct(only(Deneb, Electra), partial_getter(copy))]
+    #[superstruct(only(Deneb, Electra, Fulu), partial_getter(copy))]
     #[serde(with = "serde_utils::quoted_u64")]
     pub excess_blob_gas: u64,
 }
@@ -114,6 +114,7 @@ impl<E: EthSpec> ExecutionPayload<E> {
             ForkName::Capella => ExecutionPayloadCapella::from_ssz_bytes(bytes).map(Self::Capella),
             ForkName::Deneb => ExecutionPayloadDeneb::from_ssz_bytes(bytes).map(Self::Deneb),
             ForkName::Electra => ExecutionPayloadElectra::from_ssz_bytes(bytes).map(Self::Electra),
+            ForkName::Fulu => ExecutionPayloadFulu::from_ssz_bytes(bytes).map(Self::Fulu),
         }
     }
 
@@ -127,45 +128,6 @@ impl<E: EthSpec> ExecutionPayload<E> {
             // Max size of variable length `transactions` field
             + (E::max_transactions_per_payload() * (ssz::BYTES_PER_LENGTH_OFFSET + E::max_bytes_per_transaction()))
     }
-
-    #[allow(clippy::arithmetic_side_effects)]
-    /// Returns the maximum size of an execution payload.
-    pub fn max_execution_payload_capella_size() -> usize {
-        // Fixed part
-        ExecutionPayloadCapella::<E>::default().as_ssz_bytes().len()
-            // Max size of variable length `extra_data` field
-            + (E::max_extra_data_bytes() * <u8 as Encode>::ssz_fixed_len())
-            // Max size of variable length `transactions` field
-            + (E::max_transactions_per_payload() * (ssz::BYTES_PER_LENGTH_OFFSET + E::max_bytes_per_transaction()))
-            // Max size of variable length `withdrawals` field
-            + (E::max_withdrawals_per_payload() * <Withdrawal as Encode>::ssz_fixed_len())
-    }
-
-    #[allow(clippy::arithmetic_side_effects)]
-    /// Returns the maximum size of an execution payload.
-    pub fn max_execution_payload_deneb_size() -> usize {
-        // Fixed part
-        ExecutionPayloadDeneb::<E>::default().as_ssz_bytes().len()
-            // Max size of variable length `extra_data` field
-            + (E::max_extra_data_bytes() * <u8 as Encode>::ssz_fixed_len())
-            // Max size of variable length `transactions` field
-            + (E::max_transactions_per_payload() * (ssz::BYTES_PER_LENGTH_OFFSET + E::max_bytes_per_transaction()))
-            // Max size of variable length `withdrawals` field
-            + (E::max_withdrawals_per_payload() * <Withdrawal as Encode>::ssz_fixed_len())
-    }
-
-    #[allow(clippy::arithmetic_side_effects)]
-    /// Returns the maximum size of an execution payload.
-    pub fn max_execution_payload_electra_size() -> usize {
-        // Fixed part
-        ExecutionPayloadElectra::<E>::default().as_ssz_bytes().len()
-            // Max size of variable length `extra_data` field
-            + (E::max_extra_data_bytes() * <u8 as Encode>::ssz_fixed_len())
-            // Max size of variable length `transactions` field
-            + (E::max_transactions_per_payload() * (ssz::BYTES_PER_LENGTH_OFFSET + E::max_bytes_per_transaction()))
-            // Max size of variable length `withdrawals` field
-            + (E::max_withdrawals_per_payload() * <Withdrawal as Encode>::ssz_fixed_len())
-    }
 }
 
 impl<E: EthSpec> ForkVersionDeserialize for ExecutionPayload<E> {
@@ -184,6 +146,7 @@ impl<E: EthSpec> ForkVersionDeserialize for ExecutionPayload<E> {
             ForkName::Capella => Self::Capella(serde_json::from_value(value).map_err(convert_err)?),
             ForkName::Deneb => Self::Deneb(serde_json::from_value(value).map_err(convert_err)?),
             ForkName::Electra => Self::Electra(serde_json::from_value(value).map_err(convert_err)?),
+            ForkName::Fulu => Self::Fulu(serde_json::from_value(value).map_err(convert_err)?),
             ForkName::Base | ForkName::Altair => {
                 return Err(serde::de::Error::custom(format!(
                     "ExecutionPayload failed to deserialize: unsupported fork '{}'",
@@ -201,6 +164,7 @@ impl<E: EthSpec> ExecutionPayload<E> {
             ExecutionPayload::Capella(_) => ForkName::Capella,
             ExecutionPayload::Deneb(_) => ForkName::Deneb,
             ExecutionPayload::Electra(_) => ForkName::Electra,
+            ExecutionPayload::Fulu(_) => ForkName::Fulu,
         }
     }
 }
diff --git a/consensus/types/src/execution_payload_header.rs b/consensus/types/src/execution_payload_header.rs
index 4bfbfee9bf..3012041b8b 100644
--- a/consensus/types/src/execution_payload_header.rs
+++ b/consensus/types/src/execution_payload_header.rs
@@ -8,7 +8,7 @@ use tree_hash::TreeHash;
 use tree_hash_derive::TreeHash;
 
 #[superstruct(
-    variants(Bellatrix, Capella, Deneb, Electra),
+    variants(Bellatrix, Capella, Deneb, Electra, Fulu),
     variant_attributes(
         derive(
             Default,
@@ -78,12 +78,12 @@ pub struct ExecutionPayloadHeader<E: EthSpec> {
     pub block_hash: ExecutionBlockHash,
     #[superstruct(getter(copy))]
     pub transactions_root: Hash256,
-    #[superstruct(only(Capella, Deneb, Electra), partial_getter(copy))]
+    #[superstruct(only(Capella, Deneb, Electra, Fulu), partial_getter(copy))]
     pub withdrawals_root: Hash256,
-    #[superstruct(only(Deneb, Electra), partial_getter(copy))]
+    #[superstruct(only(Deneb, Electra, Fulu), partial_getter(copy))]
     #[serde(with = "serde_utils::quoted_u64")]
     pub blob_gas_used: u64,
-    #[superstruct(only(Deneb, Electra), partial_getter(copy))]
+    #[superstruct(only(Deneb, Electra, Fulu), partial_getter(copy))]
     #[serde(with = "serde_utils::quoted_u64")]
     pub excess_blob_gas: u64,
 }
@@ -108,18 +108,18 @@ impl<E: EthSpec> ExecutionPayloadHeader<E> {
             ForkName::Electra => {
                 ExecutionPayloadHeaderElectra::from_ssz_bytes(bytes).map(Self::Electra)
             }
+            ForkName::Fulu => ExecutionPayloadHeaderFulu::from_ssz_bytes(bytes).map(Self::Fulu),
         }
     }
 
     #[allow(clippy::arithmetic_side_effects)]
     pub fn ssz_max_var_len_for_fork(fork_name: ForkName) -> usize {
-        // Matching here in case variable fields are added in future forks.
-        match fork_name {
-            ForkName::Base | ForkName::Altair => 0,
-            ForkName::Bellatrix | ForkName::Capella | ForkName::Deneb | ForkName::Electra => {
-                // Max size of variable length `extra_data` field
-                E::max_extra_data_bytes() * <u8 as Encode>::ssz_fixed_len()
-            }
+        // TODO(newfork): Add a new case here if there are new variable fields
+        if fork_name.bellatrix_enabled() {
+            // Max size of variable length `extra_data` field
+            E::max_extra_data_bytes() * <u8 as Encode>::ssz_fixed_len()
+        } else {
+            0
         }
     }
 
@@ -129,6 +129,7 @@ impl<E: EthSpec> ExecutionPayloadHeader<E> {
             ExecutionPayloadHeader::Capella(_) => ForkName::Capella,
             ExecutionPayloadHeader::Deneb(_) => ForkName::Deneb,
             ExecutionPayloadHeader::Electra(_) => ForkName::Electra,
+            ExecutionPayloadHeader::Fulu(_) => ForkName::Fulu,
         }
     }
 }
@@ -212,6 +213,30 @@ impl<E: EthSpec> ExecutionPayloadHeaderDeneb<E> {
     }
 }
 
+impl<E: EthSpec> ExecutionPayloadHeaderElectra<E> {
+    pub fn upgrade_to_fulu(&self) -> ExecutionPayloadHeaderFulu<E> {
+        ExecutionPayloadHeaderFulu {
+            parent_hash: self.parent_hash,
+            fee_recipient: self.fee_recipient,
+            state_root: self.state_root,
+            receipts_root: self.receipts_root,
+            logs_bloom: self.logs_bloom.clone(),
+            prev_randao: self.prev_randao,
+            block_number: self.block_number,
+            gas_limit: self.gas_limit,
+            gas_used: self.gas_used,
+            timestamp: self.timestamp,
+            extra_data: self.extra_data.clone(),
+            base_fee_per_gas: self.base_fee_per_gas,
+            block_hash: self.block_hash,
+            transactions_root: self.transactions_root,
+            withdrawals_root: self.withdrawals_root,
+            blob_gas_used: self.blob_gas_used,
+            excess_blob_gas: self.excess_blob_gas,
+        }
+    }
+}
+
 impl<'a, E: EthSpec> From<&'a ExecutionPayloadBellatrix<E>> for ExecutionPayloadHeaderBellatrix<E> {
     fn from(payload: &'a ExecutionPayloadBellatrix<E>) -> Self {
         Self {
@@ -303,6 +328,30 @@ impl<'a, E: EthSpec> From<&'a ExecutionPayloadElectra<E>> for ExecutionPayloadHe
     }
 }
 
+impl<'a, E: EthSpec> From<&'a ExecutionPayloadFulu<E>> for ExecutionPayloadHeaderFulu<E> {
+    fn from(payload: &'a ExecutionPayloadFulu<E>) -> Self {
+        Self {
+            parent_hash: payload.parent_hash,
+            fee_recipient: payload.fee_recipient,
+            state_root: payload.state_root,
+            receipts_root: payload.receipts_root,
+            logs_bloom: payload.logs_bloom.clone(),
+            prev_randao: payload.prev_randao,
+            block_number: payload.block_number,
+            gas_limit: payload.gas_limit,
+            gas_used: payload.gas_used,
+            timestamp: payload.timestamp,
+            extra_data: payload.extra_data.clone(),
+            base_fee_per_gas: payload.base_fee_per_gas,
+            block_hash: payload.block_hash,
+            transactions_root: payload.transactions.tree_hash_root(),
+            withdrawals_root: payload.withdrawals.tree_hash_root(),
+            blob_gas_used: payload.blob_gas_used,
+            excess_blob_gas: payload.excess_blob_gas,
+        }
+    }
+}
+
 // These impls are required to work around an inelegance in `to_execution_payload_header`.
 // They only clone headers so they should be relatively cheap.
 impl<'a, E: EthSpec> From<&'a Self> for ExecutionPayloadHeaderBellatrix<E> {
@@ -329,6 +378,12 @@ impl<'a, E: EthSpec> From<&'a Self> for ExecutionPayloadHeaderElectra<E> {
     }
 }
 
+impl<'a, E: EthSpec> From<&'a Self> for ExecutionPayloadHeaderFulu<E> {
+    fn from(payload: &'a Self) -> Self {
+        payload.clone()
+    }
+}
+
 impl<'a, E: EthSpec> From<ExecutionPayloadRef<'a, E>> for ExecutionPayloadHeader<E> {
     fn from(payload: ExecutionPayloadRef<'a, E>) -> Self {
         map_execution_payload_ref_into_execution_payload_header!(
@@ -387,6 +442,9 @@ impl<E: EthSpec> ExecutionPayloadHeaderRefMut<'_, E> {
             ExecutionPayloadHeaderRefMut::Electra(mut_ref) => {
                 *mut_ref = header.try_into()?;
             }
+            ExecutionPayloadHeaderRefMut::Fulu(mut_ref) => {
+                *mut_ref = header.try_into()?;
+            }
         }
         Ok(())
     }
@@ -404,6 +462,16 @@ impl<E: EthSpec> TryFrom<ExecutionPayloadHeader<E>> for ExecutionPayloadHeaderEl
     }
 }
 
+impl<E: EthSpec> TryFrom<ExecutionPayloadHeader<E>> for ExecutionPayloadHeaderFulu<E> {
+    type Error = BeaconStateError;
+    fn try_from(header: ExecutionPayloadHeader<E>) -> Result<Self, Self::Error> {
+        match header {
+            ExecutionPayloadHeader::Fulu(execution_payload_header) => Ok(execution_payload_header),
+            _ => Err(BeaconStateError::IncorrectStateVariant),
+        }
+    }
+}
+
 impl<E: EthSpec> ForkVersionDeserialize for ExecutionPayloadHeader<E> {
     fn deserialize_by_fork<'de, D: serde::Deserializer<'de>>(
         value: serde_json::value::Value,
@@ -423,6 +491,7 @@ impl<E: EthSpec> ForkVersionDeserialize for ExecutionPayloadHeader<E> {
             ForkName::Capella => Self::Capella(serde_json::from_value(value).map_err(convert_err)?),
             ForkName::Deneb => Self::Deneb(serde_json::from_value(value).map_err(convert_err)?),
             ForkName::Electra => Self::Electra(serde_json::from_value(value).map_err(convert_err)?),
+            ForkName::Fulu => Self::Fulu(serde_json::from_value(value).map_err(convert_err)?),
             ForkName::Base | ForkName::Altair => {
                 return Err(serde::de::Error::custom(format!(
                     "ExecutionPayloadHeader failed to deserialize: unsupported fork '{}'",
diff --git a/consensus/types/src/execution_requests.rs b/consensus/types/src/execution_requests.rs
index 96a3905420..223c6444cc 100644
--- a/consensus/types/src/execution_requests.rs
+++ b/consensus/types/src/execution_requests.rs
@@ -43,10 +43,29 @@ impl<E: EthSpec> ExecutionRequests<E> {
     /// Returns the encoding according to EIP-7685 to send
     /// to the execution layer over the engine api.
     pub fn get_execution_requests_list(&self) -> Vec<Bytes> {
-        let deposit_bytes = Bytes::from(self.deposits.as_ssz_bytes());
-        let withdrawal_bytes = Bytes::from(self.withdrawals.as_ssz_bytes());
-        let consolidation_bytes = Bytes::from(self.consolidations.as_ssz_bytes());
-        vec![deposit_bytes, withdrawal_bytes, consolidation_bytes]
+        let mut requests_list = Vec::new();
+        if !self.deposits.is_empty() {
+            requests_list.push(Bytes::from_iter(
+                [RequestType::Deposit.to_u8()]
+                    .into_iter()
+                    .chain(self.deposits.as_ssz_bytes()),
+            ));
+        }
+        if !self.withdrawals.is_empty() {
+            requests_list.push(Bytes::from_iter(
+                [RequestType::Withdrawal.to_u8()]
+                    .into_iter()
+                    .chain(self.withdrawals.as_ssz_bytes()),
+            ));
+        }
+        if !self.consolidations.is_empty() {
+            requests_list.push(Bytes::from_iter(
+                [RequestType::Consolidation.to_u8()]
+                    .into_iter()
+                    .chain(self.consolidations.as_ssz_bytes()),
+            ));
+        }
+        requests_list
     }
 
     /// Generate the execution layer `requests_hash` based on EIP-7685.
@@ -55,9 +74,8 @@ impl<E: EthSpec> ExecutionRequests<E> {
     pub fn requests_hash(&self) -> Hash256 {
         let mut hasher = DynamicContext::new();
 
-        for (i, request) in self.get_execution_requests_list().iter().enumerate() {
+        for request in self.get_execution_requests_list().iter() {
             let mut request_hasher = DynamicContext::new();
-            request_hasher.update(&[i as u8]);
             request_hasher.update(request);
             let request_hash = request_hasher.finalize();
 
@@ -68,16 +86,16 @@ impl<E: EthSpec> ExecutionRequests<E> {
     }
 }
 
-/// This is used to index into the `execution_requests` array.
+/// The prefix types for `ExecutionRequest` objects.
 #[derive(Debug, Copy, Clone)]
-pub enum RequestPrefix {
+pub enum RequestType {
     Deposit,
     Withdrawal,
     Consolidation,
 }
 
-impl RequestPrefix {
-    pub fn from_prefix(prefix: u8) -> Option<Self> {
+impl RequestType {
+    pub fn from_u8(prefix: u8) -> Option<Self> {
         match prefix {
             0 => Some(Self::Deposit),
             1 => Some(Self::Withdrawal),
@@ -85,6 +103,13 @@ impl RequestPrefix {
             _ => None,
         }
     }
+    pub fn to_u8(&self) -> u8 {
+        match self {
+            Self::Deposit => 0,
+            Self::Withdrawal => 1,
+            Self::Consolidation => 2,
+        }
+    }
 }
 
 #[cfg(test)]
diff --git a/consensus/types/src/fork_context.rs b/consensus/types/src/fork_context.rs
index 0f7f0eb769..33f1c51d44 100644
--- a/consensus/types/src/fork_context.rs
+++ b/consensus/types/src/fork_context.rs
@@ -69,6 +69,13 @@ impl ForkContext {
             ));
         }
 
+        if spec.fulu_fork_epoch.is_some() {
+            fork_to_digest.push((
+                ForkName::Fulu,
+                ChainSpec::compute_fork_digest(spec.fulu_fork_version, genesis_validators_root),
+            ));
+        }
+
         let fork_to_digest: HashMap<ForkName, [u8; 4]> = fork_to_digest.into_iter().collect();
 
         let digest_to_fork = fork_to_digest
diff --git a/consensus/types/src/fork_name.rs b/consensus/types/src/fork_name.rs
index 51a5b3813b..40557e0cb9 100644
--- a/consensus/types/src/fork_name.rs
+++ b/consensus/types/src/fork_name.rs
@@ -17,6 +17,7 @@ pub enum ForkName {
     Capella,
     Deneb,
     Electra,
+    Fulu,
 }
 
 impl ForkName {
@@ -28,6 +29,7 @@ impl ForkName {
             ForkName::Capella,
             ForkName::Deneb,
             ForkName::Electra,
+            ForkName::Fulu,
         ]
     }
 
@@ -38,6 +40,7 @@ impl ForkName {
             (ForkName::Capella, spec.capella_fork_epoch),
             (ForkName::Deneb, spec.deneb_fork_epoch),
             (ForkName::Electra, spec.electra_fork_epoch),
+            (ForkName::Fulu, spec.fulu_fork_epoch),
         ]
     }
 
@@ -46,6 +49,13 @@ impl ForkName {
         *ForkName::list_all().last().unwrap()
     }
 
+    /// Returns the fork primarily used for testing purposes.
+    /// This fork serves as the baseline for many tests, and the goal
+    /// is to ensure features are passing on this fork.
+    pub fn latest_stable() -> ForkName {
+        ForkName::Electra
+    }
+
     /// Set the activation slots in the given `ChainSpec` so that the fork named by `self`
     /// is the only fork in effect from genesis.
     pub fn make_genesis_spec(&self, mut spec: ChainSpec) -> ChainSpec {
@@ -57,6 +67,7 @@ impl ForkName {
                 spec.capella_fork_epoch = None;
                 spec.deneb_fork_epoch = None;
                 spec.electra_fork_epoch = None;
+                spec.fulu_fork_epoch = None;
                 spec
             }
             ForkName::Altair => {
@@ -65,6 +76,7 @@ impl ForkName {
                 spec.capella_fork_epoch = None;
                 spec.deneb_fork_epoch = None;
                 spec.electra_fork_epoch = None;
+                spec.fulu_fork_epoch = None;
                 spec
             }
             ForkName::Bellatrix => {
@@ -73,6 +85,7 @@ impl ForkName {
                 spec.capella_fork_epoch = None;
                 spec.deneb_fork_epoch = None;
                 spec.electra_fork_epoch = None;
+                spec.fulu_fork_epoch = None;
                 spec
             }
             ForkName::Capella => {
@@ -81,6 +94,7 @@ impl ForkName {
                 spec.capella_fork_epoch = Some(Epoch::new(0));
                 spec.deneb_fork_epoch = None;
                 spec.electra_fork_epoch = None;
+                spec.fulu_fork_epoch = None;
                 spec
             }
             ForkName::Deneb => {
@@ -89,6 +103,7 @@ impl ForkName {
                 spec.capella_fork_epoch = Some(Epoch::new(0));
                 spec.deneb_fork_epoch = Some(Epoch::new(0));
                 spec.electra_fork_epoch = None;
+                spec.fulu_fork_epoch = None;
                 spec
             }
             ForkName::Electra => {
@@ -97,6 +112,16 @@ impl ForkName {
                 spec.capella_fork_epoch = Some(Epoch::new(0));
                 spec.deneb_fork_epoch = Some(Epoch::new(0));
                 spec.electra_fork_epoch = Some(Epoch::new(0));
+                spec.fulu_fork_epoch = None;
+                spec
+            }
+            ForkName::Fulu => {
+                spec.altair_fork_epoch = Some(Epoch::new(0));
+                spec.bellatrix_fork_epoch = Some(Epoch::new(0));
+                spec.capella_fork_epoch = Some(Epoch::new(0));
+                spec.deneb_fork_epoch = Some(Epoch::new(0));
+                spec.electra_fork_epoch = Some(Epoch::new(0));
+                spec.fulu_fork_epoch = Some(Epoch::new(0));
                 spec
             }
         }
@@ -113,6 +138,7 @@ impl ForkName {
             ForkName::Capella => Some(ForkName::Bellatrix),
             ForkName::Deneb => Some(ForkName::Capella),
             ForkName::Electra => Some(ForkName::Deneb),
+            ForkName::Fulu => Some(ForkName::Electra),
         }
     }
 
@@ -126,7 +152,8 @@ impl ForkName {
             ForkName::Bellatrix => Some(ForkName::Capella),
             ForkName::Capella => Some(ForkName::Deneb),
             ForkName::Deneb => Some(ForkName::Electra),
-            ForkName::Electra => None,
+            ForkName::Electra => Some(ForkName::Fulu),
+            ForkName::Fulu => None,
         }
     }
 
@@ -149,6 +176,10 @@ impl ForkName {
     pub fn electra_enabled(self) -> bool {
         self >= ForkName::Electra
     }
+
+    pub fn fulu_enabled(self) -> bool {
+        self >= ForkName::Fulu
+    }
 }
 
 /// Map a fork name into a fork-versioned superstruct type like `BeaconBlock`.
@@ -200,6 +231,10 @@ macro_rules! map_fork_name_with {
                 let (value, extra_data) = $body;
                 ($t::Electra(value), extra_data)
             }
+            ForkName::Fulu => {
+                let (value, extra_data) = $body;
+                ($t::Fulu(value), extra_data)
+            }
         }
     };
 }
@@ -215,6 +250,7 @@ impl FromStr for ForkName {
             "capella" => ForkName::Capella,
             "deneb" => ForkName::Deneb,
             "electra" => ForkName::Electra,
+            "fulu" => ForkName::Fulu,
             _ => return Err(format!("unknown fork name: {}", fork_name)),
         })
     }
@@ -229,6 +265,7 @@ impl Display for ForkName {
             ForkName::Capella => "capella".fmt(f),
             ForkName::Deneb => "deneb".fmt(f),
             ForkName::Electra => "electra".fmt(f),
+            ForkName::Fulu => "fulu".fmt(f),
         }
     }
 }
diff --git a/consensus/types/src/graffiti.rs b/consensus/types/src/graffiti.rs
index 08f8573c6d..f781aacabd 100644
--- a/consensus/types/src/graffiti.rs
+++ b/consensus/types/src/graffiti.rs
@@ -57,7 +57,7 @@ impl FromStr for GraffitiString {
     type Err = String;
 
     fn from_str(s: &str) -> Result<Self, Self::Err> {
-        if s.as_bytes().len() > GRAFFITI_BYTES_LEN {
+        if s.len() > GRAFFITI_BYTES_LEN {
             return Err(format!(
                 "Graffiti exceeds max length {}",
                 GRAFFITI_BYTES_LEN
diff --git a/consensus/types/src/lib.rs b/consensus/types/src/lib.rs
index 70c84bee96..8e664d99fa 100644
--- a/consensus/types/src/lib.rs
+++ b/consensus/types/src/lib.rs
@@ -107,10 +107,12 @@ pub mod slot_data;
 pub mod sqlite;
 
 pub mod blob_sidecar;
+pub mod data_column_custody_group;
 pub mod data_column_sidecar;
 pub mod data_column_subnet_id;
 pub mod light_client_header;
 pub mod non_zero_usize;
+pub mod runtime_fixed_vector;
 pub mod runtime_var_list;
 
 pub use crate::activation_queue::ActivationQueue;
@@ -119,7 +121,7 @@ pub use crate::aggregate_and_proof::{
 };
 pub use crate::attestation::{
     Attestation, AttestationBase, AttestationElectra, AttestationRef, AttestationRefMut,
-    Error as AttestationError,
+    Error as AttestationError, SingleAttestation,
 };
 pub use crate::attestation_data::AttestationData;
 pub use crate::attestation_duty::AttestationDuty;
@@ -129,13 +131,13 @@ pub use crate::attester_slashing::{
 };
 pub use crate::beacon_block::{
     BeaconBlock, BeaconBlockAltair, BeaconBlockBase, BeaconBlockBellatrix, BeaconBlockCapella,
-    BeaconBlockDeneb, BeaconBlockElectra, BeaconBlockRef, BeaconBlockRefMut, BlindedBeaconBlock,
-    BlockImportSource, EmptyBlock,
+    BeaconBlockDeneb, BeaconBlockElectra, BeaconBlockFulu, BeaconBlockRef, BeaconBlockRefMut,
+    BlindedBeaconBlock, BlockImportSource, EmptyBlock,
 };
 pub use crate::beacon_block_body::{
     BeaconBlockBody, BeaconBlockBodyAltair, BeaconBlockBodyBase, BeaconBlockBodyBellatrix,
-    BeaconBlockBodyCapella, BeaconBlockBodyDeneb, BeaconBlockBodyElectra, BeaconBlockBodyRef,
-    BeaconBlockBodyRefMut,
+    BeaconBlockBodyCapella, BeaconBlockBodyDeneb, BeaconBlockBodyElectra, BeaconBlockBodyFulu,
+    BeaconBlockBodyRef, BeaconBlockBodyRefMut,
 };
 pub use crate::beacon_block_header::BeaconBlockHeader;
 pub use crate::beacon_committee::{BeaconCommittee, OwnedBeaconCommittee};
@@ -145,7 +147,7 @@ pub use crate::bls_to_execution_change::BlsToExecutionChange;
 pub use crate::chain_spec::{ChainSpec, Config, Domain};
 pub use crate::checkpoint::Checkpoint;
 pub use crate::config_and_preset::{
-    ConfigAndPreset, ConfigAndPresetCapella, ConfigAndPresetDeneb, ConfigAndPresetElectra,
+    ConfigAndPreset, ConfigAndPresetDeneb, ConfigAndPresetElectra, ConfigAndPresetFulu,
 };
 pub use crate::consolidation_request::ConsolidationRequest;
 pub use crate::contribution_and_proof::ContributionAndProof;
@@ -166,14 +168,15 @@ pub use crate::execution_block_hash::ExecutionBlockHash;
 pub use crate::execution_block_header::{EncodableExecutionBlockHeader, ExecutionBlockHeader};
 pub use crate::execution_payload::{
     ExecutionPayload, ExecutionPayloadBellatrix, ExecutionPayloadCapella, ExecutionPayloadDeneb,
-    ExecutionPayloadElectra, ExecutionPayloadRef, Transaction, Transactions, Withdrawals,
+    ExecutionPayloadElectra, ExecutionPayloadFulu, ExecutionPayloadRef, Transaction, Transactions,
+    Withdrawals,
 };
 pub use crate::execution_payload_header::{
     ExecutionPayloadHeader, ExecutionPayloadHeaderBellatrix, ExecutionPayloadHeaderCapella,
-    ExecutionPayloadHeaderDeneb, ExecutionPayloadHeaderElectra, ExecutionPayloadHeaderRef,
-    ExecutionPayloadHeaderRefMut,
+    ExecutionPayloadHeaderDeneb, ExecutionPayloadHeaderElectra, ExecutionPayloadHeaderFulu,
+    ExecutionPayloadHeaderRef, ExecutionPayloadHeaderRefMut,
 };
-pub use crate::execution_requests::{ExecutionRequests, RequestPrefix};
+pub use crate::execution_requests::{ExecutionRequests, RequestType};
 pub use crate::fork::Fork;
 pub use crate::fork_context::ForkContext;
 pub use crate::fork_data::ForkData;
@@ -189,31 +192,33 @@ pub use crate::indexed_attestation::{
 };
 pub use crate::light_client_bootstrap::{
     LightClientBootstrap, LightClientBootstrapAltair, LightClientBootstrapCapella,
-    LightClientBootstrapDeneb, LightClientBootstrapElectra,
+    LightClientBootstrapDeneb, LightClientBootstrapElectra, LightClientBootstrapFulu,
 };
 pub use crate::light_client_finality_update::{
     LightClientFinalityUpdate, LightClientFinalityUpdateAltair, LightClientFinalityUpdateCapella,
     LightClientFinalityUpdateDeneb, LightClientFinalityUpdateElectra,
+    LightClientFinalityUpdateFulu,
 };
 pub use crate::light_client_header::{
     LightClientHeader, LightClientHeaderAltair, LightClientHeaderCapella, LightClientHeaderDeneb,
-    LightClientHeaderElectra,
+    LightClientHeaderElectra, LightClientHeaderFulu,
 };
 pub use crate::light_client_optimistic_update::{
     LightClientOptimisticUpdate, LightClientOptimisticUpdateAltair,
     LightClientOptimisticUpdateCapella, LightClientOptimisticUpdateDeneb,
-    LightClientOptimisticUpdateElectra,
+    LightClientOptimisticUpdateElectra, LightClientOptimisticUpdateFulu,
 };
 pub use crate::light_client_update::{
     Error as LightClientUpdateError, LightClientUpdate, LightClientUpdateAltair,
-    LightClientUpdateCapella, LightClientUpdateDeneb, LightClientUpdateElectra, MerkleProof,
+    LightClientUpdateCapella, LightClientUpdateDeneb, LightClientUpdateElectra,
+    LightClientUpdateFulu, MerkleProof,
 };
 pub use crate::participation_flags::ParticipationFlags;
 pub use crate::payload::{
     AbstractExecPayload, BlindedPayload, BlindedPayloadBellatrix, BlindedPayloadCapella,
-    BlindedPayloadDeneb, BlindedPayloadElectra, BlindedPayloadRef, BlockType, ExecPayload,
-    FullPayload, FullPayloadBellatrix, FullPayloadCapella, FullPayloadDeneb, FullPayloadElectra,
-    FullPayloadRef, OwnedExecPayload,
+    BlindedPayloadDeneb, BlindedPayloadElectra, BlindedPayloadFulu, BlindedPayloadRef, BlockType,
+    ExecPayload, FullPayload, FullPayloadBellatrix, FullPayloadCapella, FullPayloadDeneb,
+    FullPayloadElectra, FullPayloadFulu, FullPayloadRef, OwnedExecPayload,
 };
 pub use crate::pending_attestation::PendingAttestation;
 pub use crate::pending_consolidation::PendingConsolidation;
@@ -221,10 +226,12 @@ pub use crate::pending_deposit::PendingDeposit;
 pub use crate::pending_partial_withdrawal::PendingPartialWithdrawal;
 pub use crate::preset::{
     AltairPreset, BasePreset, BellatrixPreset, CapellaPreset, DenebPreset, ElectraPreset,
+    FuluPreset,
 };
 pub use crate::proposer_preparation_data::ProposerPreparationData;
 pub use crate::proposer_slashing::ProposerSlashing;
 pub use crate::relative_epoch::{Error as RelativeEpochError, RelativeEpoch};
+pub use crate::runtime_fixed_vector::RuntimeFixedVector;
 pub use crate::runtime_var_list::RuntimeVariableList;
 pub use crate::selection_proof::SelectionProof;
 pub use crate::shuffling_id::AttestationShufflingId;
@@ -235,7 +242,7 @@ pub use crate::signed_beacon_block::{
     ssz_tagged_signed_beacon_block, ssz_tagged_signed_beacon_block_arc, SignedBeaconBlock,
     SignedBeaconBlockAltair, SignedBeaconBlockBase, SignedBeaconBlockBellatrix,
     SignedBeaconBlockCapella, SignedBeaconBlockDeneb, SignedBeaconBlockElectra,
-    SignedBeaconBlockHash, SignedBlindedBeaconBlock,
+    SignedBeaconBlockFulu, SignedBeaconBlockHash, SignedBlindedBeaconBlock,
 };
 pub use crate::signed_beacon_block_header::SignedBeaconBlockHeader;
 pub use crate::signed_bls_to_execution_change::SignedBlsToExecutionChange;
diff --git a/consensus/types/src/light_client_bootstrap.rs b/consensus/types/src/light_client_bootstrap.rs
index 21a7e5416f..aa0d8836d1 100644
--- a/consensus/types/src/light_client_bootstrap.rs
+++ b/consensus/types/src/light_client_bootstrap.rs
@@ -2,7 +2,7 @@ use crate::{
     light_client_update::*, test_utils::TestRandom, BeaconState, ChainSpec, EthSpec, FixedVector,
     ForkName, ForkVersionDeserialize, Hash256, LightClientHeader, LightClientHeaderAltair,
     LightClientHeaderCapella, LightClientHeaderDeneb, LightClientHeaderElectra,
-    SignedBlindedBeaconBlock, Slot, SyncCommittee,
+    LightClientHeaderFulu, SignedBlindedBeaconBlock, Slot, SyncCommittee,
 };
 use derivative::Derivative;
 use serde::{Deserialize, Deserializer, Serialize};
@@ -17,7 +17,7 @@ use tree_hash_derive::TreeHash;
 /// A LightClientBootstrap is the initializer we send over to light_client nodes
 /// that are trying to generate their basic storage when booting up.
 #[superstruct(
-    variants(Altair, Capella, Deneb, Electra),
+    variants(Altair, Capella, Deneb, Electra, Fulu),
     variant_attributes(
         derive(
             Debug,
@@ -54,6 +54,8 @@ pub struct LightClientBootstrap<E: EthSpec> {
     pub header: LightClientHeaderDeneb<E>,
     #[superstruct(only(Electra), partial_getter(rename = "header_electra"))]
     pub header: LightClientHeaderElectra<E>,
+    #[superstruct(only(Fulu), partial_getter(rename = "header_fulu"))]
+    pub header: LightClientHeaderFulu<E>,
     /// The `SyncCommittee` used in the requested period.
     pub current_sync_committee: Arc<SyncCommittee<E>>,
     /// Merkle proof for sync committee
@@ -63,7 +65,7 @@ pub struct LightClientBootstrap<E: EthSpec> {
     )]
     pub current_sync_committee_branch: FixedVector<Hash256, CurrentSyncCommitteeProofLen>,
     #[superstruct(
-        only(Electra),
+        only(Electra, Fulu),
         partial_getter(rename = "current_sync_committee_branch_electra")
     )]
     pub current_sync_committee_branch: FixedVector<Hash256, CurrentSyncCommitteeProofLenElectra>,
@@ -79,6 +81,7 @@ impl<E: EthSpec> LightClientBootstrap<E> {
             Self::Capella(_) => func(ForkName::Capella),
             Self::Deneb(_) => func(ForkName::Deneb),
             Self::Electra(_) => func(ForkName::Electra),
+            Self::Fulu(_) => func(ForkName::Fulu),
         }
     }
 
@@ -97,6 +100,7 @@ impl<E: EthSpec> LightClientBootstrap<E> {
             ForkName::Capella => Self::Capella(LightClientBootstrapCapella::from_ssz_bytes(bytes)?),
             ForkName::Deneb => Self::Deneb(LightClientBootstrapDeneb::from_ssz_bytes(bytes)?),
             ForkName::Electra => Self::Electra(LightClientBootstrapElectra::from_ssz_bytes(bytes)?),
+            ForkName::Fulu => Self::Fulu(LightClientBootstrapFulu::from_ssz_bytes(bytes)?),
             ForkName::Base => {
                 return Err(ssz::DecodeError::BytesInvalid(format!(
                     "LightClientBootstrap decoding for {fork_name} not implemented"
@@ -117,6 +121,7 @@ impl<E: EthSpec> LightClientBootstrap<E> {
             ForkName::Capella => <LightClientBootstrapCapella<E> as Encode>::ssz_fixed_len(),
             ForkName::Deneb => <LightClientBootstrapDeneb<E> as Encode>::ssz_fixed_len(),
             ForkName::Electra => <LightClientBootstrapElectra<E> as Encode>::ssz_fixed_len(),
+            ForkName::Fulu => <LightClientBootstrapFulu<E> as Encode>::ssz_fixed_len(),
         };
         fixed_len + LightClientHeader::<E>::ssz_max_var_len_for_fork(fork_name)
     }
@@ -152,6 +157,11 @@ impl<E: EthSpec> LightClientBootstrap<E> {
                 current_sync_committee,
                 current_sync_committee_branch: current_sync_committee_branch.into(),
             }),
+            ForkName::Fulu => Self::Fulu(LightClientBootstrapFulu {
+                header: LightClientHeaderFulu::block_to_light_client_header(block)?,
+                current_sync_committee,
+                current_sync_committee_branch: current_sync_committee_branch.into(),
+            }),
         };
 
         Ok(light_client_bootstrap)
@@ -192,6 +202,11 @@ impl<E: EthSpec> LightClientBootstrap<E> {
                 current_sync_committee,
                 current_sync_committee_branch: current_sync_committee_branch.into(),
             }),
+            ForkName::Fulu => Self::Fulu(LightClientBootstrapFulu {
+                header: LightClientHeaderFulu::block_to_light_client_header(block)?,
+                current_sync_committee,
+                current_sync_committee_branch: current_sync_committee_branch.into(),
+            }),
         };
 
         Ok(light_client_bootstrap)
@@ -241,4 +256,10 @@ mod tests {
         use crate::{LightClientBootstrapElectra, MainnetEthSpec};
         ssz_tests!(LightClientBootstrapElectra<MainnetEthSpec>);
     }
+
+    #[cfg(test)]
+    mod fulu {
+        use crate::{LightClientBootstrapFulu, MainnetEthSpec};
+        ssz_tests!(LightClientBootstrapFulu<MainnetEthSpec>);
+    }
 }
diff --git a/consensus/types/src/light_client_finality_update.rs b/consensus/types/src/light_client_finality_update.rs
index ba2f2083cd..ee3b53c853 100644
--- a/consensus/types/src/light_client_finality_update.rs
+++ b/consensus/types/src/light_client_finality_update.rs
@@ -3,7 +3,7 @@ use crate::ChainSpec;
 use crate::{
     light_client_update::*, test_utils::TestRandom, ForkName, ForkVersionDeserialize,
     LightClientHeaderAltair, LightClientHeaderCapella, LightClientHeaderDeneb,
-    LightClientHeaderElectra, SignedBlindedBeaconBlock,
+    LightClientHeaderElectra, LightClientHeaderFulu, SignedBlindedBeaconBlock,
 };
 use derivative::Derivative;
 use serde::{Deserialize, Deserializer, Serialize};
@@ -16,7 +16,7 @@ use test_random_derive::TestRandom;
 use tree_hash_derive::TreeHash;
 
 #[superstruct(
-    variants(Altair, Capella, Deneb, Electra),
+    variants(Altair, Capella, Deneb, Electra, Fulu),
     variant_attributes(
         derive(
             Debug,
@@ -53,6 +53,8 @@ pub struct LightClientFinalityUpdate<E: EthSpec> {
     pub attested_header: LightClientHeaderDeneb<E>,
     #[superstruct(only(Electra), partial_getter(rename = "attested_header_electra"))]
     pub attested_header: LightClientHeaderElectra<E>,
+    #[superstruct(only(Fulu), partial_getter(rename = "attested_header_fulu"))]
+    pub attested_header: LightClientHeaderFulu<E>,
     /// The last `BeaconBlockHeader` from the last attested finalized block (end of epoch).
     #[superstruct(only(Altair), partial_getter(rename = "finalized_header_altair"))]
     pub finalized_header: LightClientHeaderAltair<E>,
@@ -62,13 +64,18 @@ pub struct LightClientFinalityUpdate<E: EthSpec> {
     pub finalized_header: LightClientHeaderDeneb<E>,
     #[superstruct(only(Electra), partial_getter(rename = "finalized_header_electra"))]
     pub finalized_header: LightClientHeaderElectra<E>,
+    #[superstruct(only(Fulu), partial_getter(rename = "finalized_header_fulu"))]
+    pub finalized_header: LightClientHeaderFulu<E>,
     /// Merkle proof attesting finalized header.
     #[superstruct(
         only(Altair, Capella, Deneb),
         partial_getter(rename = "finality_branch_altair")
     )]
     pub finality_branch: FixedVector<Hash256, FinalizedRootProofLen>,
-    #[superstruct(only(Electra), partial_getter(rename = "finality_branch_electra"))]
+    #[superstruct(
+        only(Electra, Fulu),
+        partial_getter(rename = "finality_branch_electra")
+    )]
     pub finality_branch: FixedVector<Hash256, FinalizedRootProofLenElectra>,
     /// current sync aggregate
     pub sync_aggregate: SyncAggregate<E>,
@@ -135,6 +142,17 @@ impl<E: EthSpec> LightClientFinalityUpdate<E> {
                 sync_aggregate,
                 signature_slot,
             }),
+            ForkName::Fulu => Self::Fulu(LightClientFinalityUpdateFulu {
+                attested_header: LightClientHeaderFulu::block_to_light_client_header(
+                    attested_block,
+                )?,
+                finalized_header: LightClientHeaderFulu::block_to_light_client_header(
+                    finalized_block,
+                )?,
+                finality_branch: finality_branch.into(),
+                sync_aggregate,
+                signature_slot,
+            }),
 
             ForkName::Base => return Err(Error::AltairForkNotActive),
         };
@@ -151,6 +169,7 @@ impl<E: EthSpec> LightClientFinalityUpdate<E> {
             Self::Capella(_) => func(ForkName::Capella),
             Self::Deneb(_) => func(ForkName::Deneb),
             Self::Electra(_) => func(ForkName::Electra),
+            Self::Fulu(_) => func(ForkName::Fulu),
         }
     }
 
@@ -173,6 +192,7 @@ impl<E: EthSpec> LightClientFinalityUpdate<E> {
             ForkName::Electra => {
                 Self::Electra(LightClientFinalityUpdateElectra::from_ssz_bytes(bytes)?)
             }
+            ForkName::Fulu => Self::Fulu(LightClientFinalityUpdateFulu::from_ssz_bytes(bytes)?),
             ForkName::Base => {
                 return Err(ssz::DecodeError::BytesInvalid(format!(
                     "LightClientFinalityUpdate decoding for {fork_name} not implemented"
@@ -193,6 +213,7 @@ impl<E: EthSpec> LightClientFinalityUpdate<E> {
             ForkName::Capella => <LightClientFinalityUpdateCapella<E> as Encode>::ssz_fixed_len(),
             ForkName::Deneb => <LightClientFinalityUpdateDeneb<E> as Encode>::ssz_fixed_len(),
             ForkName::Electra => <LightClientFinalityUpdateElectra<E> as Encode>::ssz_fixed_len(),
+            ForkName::Fulu => <LightClientFinalityUpdateFulu<E> as Encode>::ssz_fixed_len(),
         };
         // `2 *` because there are two headers in the update
         fixed_size + 2 * LightClientHeader::<E>::ssz_max_var_len_for_fork(fork_name)
@@ -255,4 +276,10 @@ mod tests {
         use crate::{LightClientFinalityUpdateElectra, MainnetEthSpec};
         ssz_tests!(LightClientFinalityUpdateElectra<MainnetEthSpec>);
     }
+
+    #[cfg(test)]
+    mod fulu {
+        use crate::{LightClientFinalityUpdateFulu, MainnetEthSpec};
+        ssz_tests!(LightClientFinalityUpdateFulu<MainnetEthSpec>);
+    }
 }
diff --git a/consensus/types/src/light_client_header.rs b/consensus/types/src/light_client_header.rs
index 6655e0a093..0be26a7036 100644
--- a/consensus/types/src/light_client_header.rs
+++ b/consensus/types/src/light_client_header.rs
@@ -4,7 +4,8 @@ use crate::ForkVersionDeserialize;
 use crate::{light_client_update::*, BeaconBlockBody};
 use crate::{
     test_utils::TestRandom, EthSpec, ExecutionPayloadHeaderCapella, ExecutionPayloadHeaderDeneb,
-    ExecutionPayloadHeaderElectra, FixedVector, Hash256, SignedBlindedBeaconBlock,
+    ExecutionPayloadHeaderElectra, ExecutionPayloadHeaderFulu, FixedVector, Hash256,
+    SignedBlindedBeaconBlock,
 };
 use crate::{BeaconBlockHeader, ExecutionPayloadHeader};
 use derivative::Derivative;
@@ -17,7 +18,7 @@ use test_random_derive::TestRandom;
 use tree_hash_derive::TreeHash;
 
 #[superstruct(
-    variants(Altair, Capella, Deneb, Electra),
+    variants(Altair, Capella, Deneb, Electra, Fulu),
     variant_attributes(
         derive(
             Debug,
@@ -59,8 +60,10 @@ pub struct LightClientHeader<E: EthSpec> {
         partial_getter(rename = "execution_payload_header_electra")
     )]
     pub execution: ExecutionPayloadHeaderElectra<E>,
+    #[superstruct(only(Fulu), partial_getter(rename = "execution_payload_header_fulu"))]
+    pub execution: ExecutionPayloadHeaderFulu<E>,
 
-    #[superstruct(only(Capella, Deneb, Electra))]
+    #[superstruct(only(Capella, Deneb, Electra, Fulu))]
     pub execution_branch: FixedVector<Hash256, ExecutionPayloadProofLen>,
 
     #[ssz(skip_serializing, skip_deserializing)]
@@ -92,6 +95,9 @@ impl<E: EthSpec> LightClientHeader<E> {
             ForkName::Electra => LightClientHeader::Electra(
                 LightClientHeaderElectra::block_to_light_client_header(block)?,
             ),
+            ForkName::Fulu => {
+                LightClientHeader::Fulu(LightClientHeaderFulu::block_to_light_client_header(block)?)
+            }
         };
         Ok(header)
     }
@@ -110,6 +116,9 @@ impl<E: EthSpec> LightClientHeader<E> {
             ForkName::Electra => {
                 LightClientHeader::Electra(LightClientHeaderElectra::from_ssz_bytes(bytes)?)
             }
+            ForkName::Fulu => {
+                LightClientHeader::Fulu(LightClientHeaderFulu::from_ssz_bytes(bytes)?)
+            }
             ForkName::Base => {
                 return Err(ssz::DecodeError::BytesInvalid(format!(
                     "LightClientHeader decoding for {fork_name} not implemented"
@@ -283,6 +292,48 @@ impl<E: EthSpec> Default for LightClientHeaderElectra<E> {
     }
 }
 
+impl<E: EthSpec> LightClientHeaderFulu<E> {
+    pub fn block_to_light_client_header(
+        block: &SignedBlindedBeaconBlock<E>,
+    ) -> Result<Self, Error> {
+        let payload = block
+            .message()
+            .execution_payload()?
+            .execution_payload_fulu()?;
+
+        let header = ExecutionPayloadHeaderFulu::from(payload);
+        let beacon_block_body = BeaconBlockBody::from(
+            block
+                .message()
+                .body_fulu()
+                .map_err(|_| Error::BeaconBlockBodyError)?
+                .to_owned(),
+        );
+
+        let execution_branch = beacon_block_body
+            .to_ref()
+            .block_body_merkle_proof(EXECUTION_PAYLOAD_INDEX)?;
+
+        Ok(LightClientHeaderFulu {
+            beacon: block.message().block_header(),
+            execution: header,
+            execution_branch: FixedVector::new(execution_branch)?,
+            _phantom_data: PhantomData,
+        })
+    }
+}
+
+impl<E: EthSpec> Default for LightClientHeaderFulu<E> {
+    fn default() -> Self {
+        Self {
+            beacon: BeaconBlockHeader::empty(),
+            execution: ExecutionPayloadHeaderFulu::default(),
+            execution_branch: FixedVector::default(),
+            _phantom_data: PhantomData,
+        }
+    }
+}
+
 impl<E: EthSpec> ForkVersionDeserialize for LightClientHeader<E> {
     fn deserialize_by_fork<'de, D: serde::Deserializer<'de>>(
         value: serde_json::value::Value,
@@ -301,6 +352,9 @@ impl<E: EthSpec> ForkVersionDeserialize for LightClientHeader<E> {
             ForkName::Electra => serde_json::from_value(value)
                 .map(|light_client_header| Self::Electra(light_client_header))
                 .map_err(serde::de::Error::custom),
+            ForkName::Fulu => serde_json::from_value(value)
+                .map(|light_client_header| Self::Fulu(light_client_header))
+                .map_err(serde::de::Error::custom),
             ForkName::Base => Err(serde::de::Error::custom(format!(
                 "LightClientHeader deserialization for {fork_name} not implemented"
             ))),
diff --git a/consensus/types/src/light_client_optimistic_update.rs b/consensus/types/src/light_client_optimistic_update.rs
index 209388af87..fcf357757b 100644
--- a/consensus/types/src/light_client_optimistic_update.rs
+++ b/consensus/types/src/light_client_optimistic_update.rs
@@ -2,7 +2,8 @@ use super::{EthSpec, ForkName, ForkVersionDeserialize, LightClientHeader, Slot,
 use crate::test_utils::TestRandom;
 use crate::{
     light_client_update::*, ChainSpec, LightClientHeaderAltair, LightClientHeaderCapella,
-    LightClientHeaderDeneb, LightClientHeaderElectra, SignedBlindedBeaconBlock,
+    LightClientHeaderDeneb, LightClientHeaderElectra, LightClientHeaderFulu,
+    SignedBlindedBeaconBlock,
 };
 use derivative::Derivative;
 use serde::{Deserialize, Deserializer, Serialize};
@@ -18,7 +19,7 @@ use tree_hash_derive::TreeHash;
 /// A LightClientOptimisticUpdate is the update we send on each slot,
 /// it is based off the current unfinalized epoch is verified only against BLS signature.
 #[superstruct(
-    variants(Altair, Capella, Deneb, Electra),
+    variants(Altair, Capella, Deneb, Electra, Fulu),
     variant_attributes(
         derive(
             Debug,
@@ -55,6 +56,8 @@ pub struct LightClientOptimisticUpdate<E: EthSpec> {
     pub attested_header: LightClientHeaderDeneb<E>,
     #[superstruct(only(Electra), partial_getter(rename = "attested_header_electra"))]
     pub attested_header: LightClientHeaderElectra<E>,
+    #[superstruct(only(Fulu), partial_getter(rename = "attested_header_fulu"))]
+    pub attested_header: LightClientHeaderFulu<E>,
     /// current sync aggregate
     pub sync_aggregate: SyncAggregate<E>,
     /// Slot of the sync aggregated signature
@@ -102,6 +105,13 @@ impl<E: EthSpec> LightClientOptimisticUpdate<E> {
                 sync_aggregate,
                 signature_slot,
             }),
+            ForkName::Fulu => Self::Fulu(LightClientOptimisticUpdateFulu {
+                attested_header: LightClientHeaderFulu::block_to_light_client_header(
+                    attested_block,
+                )?,
+                sync_aggregate,
+                signature_slot,
+            }),
             ForkName::Base => return Err(Error::AltairForkNotActive),
         };
 
@@ -117,6 +127,7 @@ impl<E: EthSpec> LightClientOptimisticUpdate<E> {
             Self::Capella(_) => func(ForkName::Capella),
             Self::Deneb(_) => func(ForkName::Deneb),
             Self::Electra(_) => func(ForkName::Electra),
+            Self::Fulu(_) => func(ForkName::Fulu),
         }
     }
 
@@ -155,6 +166,7 @@ impl<E: EthSpec> LightClientOptimisticUpdate<E> {
             ForkName::Electra => {
                 Self::Electra(LightClientOptimisticUpdateElectra::from_ssz_bytes(bytes)?)
             }
+            ForkName::Fulu => Self::Fulu(LightClientOptimisticUpdateFulu::from_ssz_bytes(bytes)?),
             ForkName::Base => {
                 return Err(ssz::DecodeError::BytesInvalid(format!(
                     "LightClientOptimisticUpdate decoding for {fork_name} not implemented"
@@ -175,6 +187,7 @@ impl<E: EthSpec> LightClientOptimisticUpdate<E> {
             ForkName::Capella => <LightClientOptimisticUpdateCapella<E> as Encode>::ssz_fixed_len(),
             ForkName::Deneb => <LightClientOptimisticUpdateDeneb<E> as Encode>::ssz_fixed_len(),
             ForkName::Electra => <LightClientOptimisticUpdateElectra<E> as Encode>::ssz_fixed_len(),
+            ForkName::Fulu => <LightClientOptimisticUpdateFulu<E> as Encode>::ssz_fixed_len(),
         };
         fixed_len + LightClientHeader::<E>::ssz_max_var_len_for_fork(fork_name)
     }
@@ -238,4 +251,10 @@ mod tests {
         use crate::{LightClientOptimisticUpdateElectra, MainnetEthSpec};
         ssz_tests!(LightClientOptimisticUpdateElectra<MainnetEthSpec>);
     }
+
+    #[cfg(test)]
+    mod fulu {
+        use crate::{LightClientOptimisticUpdateFulu, MainnetEthSpec};
+        ssz_tests!(LightClientOptimisticUpdateFulu<MainnetEthSpec>);
+    }
 }
diff --git a/consensus/types/src/light_client_update.rs b/consensus/types/src/light_client_update.rs
index c3a50e71c1..0dd91edc3c 100644
--- a/consensus/types/src/light_client_update.rs
+++ b/consensus/types/src/light_client_update.rs
@@ -4,7 +4,7 @@ use crate::LightClientHeader;
 use crate::{
     beacon_state, test_utils::TestRandom, ChainSpec, Epoch, ForkName, ForkVersionDeserialize,
     LightClientHeaderAltair, LightClientHeaderCapella, LightClientHeaderDeneb,
-    SignedBlindedBeaconBlock,
+    LightClientHeaderFulu, SignedBlindedBeaconBlock,
 };
 use derivative::Derivative;
 use safe_arith::ArithError;
@@ -100,7 +100,7 @@ impl From<milhouse::Error> for Error {
 /// or to sync up to the last committee period, we need to have one ready for each ALTAIR period
 /// we go over, note: there is no need to keep all of the updates from [ALTAIR_PERIOD, CURRENT_PERIOD].
 #[superstruct(
-    variants(Altair, Capella, Deneb, Electra),
+    variants(Altair, Capella, Deneb, Electra, Fulu),
     variant_attributes(
         derive(
             Debug,
@@ -137,6 +137,8 @@ pub struct LightClientUpdate<E: EthSpec> {
     pub attested_header: LightClientHeaderDeneb<E>,
     #[superstruct(only(Electra), partial_getter(rename = "attested_header_electra"))]
     pub attested_header: LightClientHeaderElectra<E>,
+    #[superstruct(only(Fulu), partial_getter(rename = "attested_header_fulu"))]
+    pub attested_header: LightClientHeaderFulu<E>,
     /// The `SyncCommittee` used in the next period.
     pub next_sync_committee: Arc<SyncCommittee<E>>,
     // Merkle proof for next sync committee
@@ -146,7 +148,7 @@ pub struct LightClientUpdate<E: EthSpec> {
     )]
     pub next_sync_committee_branch: NextSyncCommitteeBranch,
     #[superstruct(
-        only(Electra),
+        only(Electra, Fulu),
         partial_getter(rename = "next_sync_committee_branch_electra")
     )]
     pub next_sync_committee_branch: NextSyncCommitteeBranchElectra,
@@ -159,13 +161,18 @@ pub struct LightClientUpdate<E: EthSpec> {
     pub finalized_header: LightClientHeaderDeneb<E>,
     #[superstruct(only(Electra), partial_getter(rename = "finalized_header_electra"))]
     pub finalized_header: LightClientHeaderElectra<E>,
+    #[superstruct(only(Fulu), partial_getter(rename = "finalized_header_fulu"))]
+    pub finalized_header: LightClientHeaderFulu<E>,
     /// Merkle proof attesting finalized header.
     #[superstruct(
         only(Altair, Capella, Deneb),
         partial_getter(rename = "finality_branch_altair")
     )]
     pub finality_branch: FinalityBranch,
-    #[superstruct(only(Electra), partial_getter(rename = "finality_branch_electra"))]
+    #[superstruct(
+        only(Electra, Fulu),
+        partial_getter(rename = "finality_branch_electra")
+    )]
     pub finality_branch: FinalityBranchElectra,
     /// current sync aggreggate
     pub sync_aggregate: SyncAggregate<E>,
@@ -285,6 +292,26 @@ impl<E: EthSpec> LightClientUpdate<E> {
                     sync_aggregate: sync_aggregate.clone(),
                     signature_slot: block_slot,
                 })
+            }
+            ForkName::Fulu => {
+                let attested_header =
+                    LightClientHeaderFulu::block_to_light_client_header(attested_block)?;
+
+                let finalized_header = if let Some(finalized_block) = finalized_block {
+                    LightClientHeaderFulu::block_to_light_client_header(finalized_block)?
+                } else {
+                    LightClientHeaderFulu::default()
+                };
+
+                Self::Fulu(LightClientUpdateFulu {
+                    attested_header,
+                    next_sync_committee,
+                    next_sync_committee_branch: next_sync_committee_branch.into(),
+                    finalized_header,
+                    finality_branch: finality_branch.into(),
+                    sync_aggregate: sync_aggregate.clone(),
+                    signature_slot: block_slot,
+                })
             } // To add a new fork, just append the new fork variant on the latest fork. Forks that
               // have a distinct execution header will need a new LightClientUpdate variant only
               // if you need to test or support lightclient usages
@@ -301,6 +328,7 @@ impl<E: EthSpec> LightClientUpdate<E> {
             ForkName::Capella => Self::Capella(LightClientUpdateCapella::from_ssz_bytes(bytes)?),
             ForkName::Deneb => Self::Deneb(LightClientUpdateDeneb::from_ssz_bytes(bytes)?),
             ForkName::Electra => Self::Electra(LightClientUpdateElectra::from_ssz_bytes(bytes)?),
+            ForkName::Fulu => Self::Fulu(LightClientUpdateFulu::from_ssz_bytes(bytes)?),
             ForkName::Base => {
                 return Err(ssz::DecodeError::BytesInvalid(format!(
                     "LightClientUpdate decoding for {fork_name} not implemented"
@@ -317,6 +345,7 @@ impl<E: EthSpec> LightClientUpdate<E> {
             LightClientUpdate::Capella(update) => update.attested_header.beacon.slot,
             LightClientUpdate::Deneb(update) => update.attested_header.beacon.slot,
             LightClientUpdate::Electra(update) => update.attested_header.beacon.slot,
+            LightClientUpdate::Fulu(update) => update.attested_header.beacon.slot,
         }
     }
 
@@ -326,6 +355,7 @@ impl<E: EthSpec> LightClientUpdate<E> {
             LightClientUpdate::Capella(update) => update.finalized_header.beacon.slot,
             LightClientUpdate::Deneb(update) => update.finalized_header.beacon.slot,
             LightClientUpdate::Electra(update) => update.finalized_header.beacon.slot,
+            LightClientUpdate::Fulu(update) => update.finalized_header.beacon.slot,
         }
     }
 
@@ -445,6 +475,7 @@ impl<E: EthSpec> LightClientUpdate<E> {
             ForkName::Capella => <LightClientUpdateCapella<E> as Encode>::ssz_fixed_len(),
             ForkName::Deneb => <LightClientUpdateDeneb<E> as Encode>::ssz_fixed_len(),
             ForkName::Electra => <LightClientUpdateElectra<E> as Encode>::ssz_fixed_len(),
+            ForkName::Fulu => <LightClientUpdateFulu<E> as Encode>::ssz_fixed_len(),
         };
         fixed_len + 2 * LightClientHeader::<E>::ssz_max_var_len_for_fork(fork_name)
     }
@@ -458,6 +489,7 @@ impl<E: EthSpec> LightClientUpdate<E> {
             Self::Capella(_) => func(ForkName::Capella),
             Self::Deneb(_) => func(ForkName::Deneb),
             Self::Electra(_) => func(ForkName::Electra),
+            Self::Fulu(_) => func(ForkName::Fulu),
         }
     }
 }
@@ -513,6 +545,13 @@ mod tests {
         ssz_tests!(LightClientUpdateElectra<MainnetEthSpec>);
     }
 
+    #[cfg(test)]
+    mod fulu {
+        use super::*;
+        use crate::MainnetEthSpec;
+        ssz_tests!(LightClientUpdateFulu<MainnetEthSpec>);
+    }
+
     #[test]
     fn finalized_root_params() {
         assert!(2usize.pow(FINALIZED_ROOT_PROOF_LEN as u32) <= FINALIZED_ROOT_INDEX);
diff --git a/consensus/types/src/payload.rs b/consensus/types/src/payload.rs
index e68801840a..abc9afd34c 100644
--- a/consensus/types/src/payload.rs
+++ b/consensus/types/src/payload.rs
@@ -84,13 +84,15 @@ pub trait AbstractExecPayload<E: EthSpec>:
     + TryInto<Self::Capella>
     + TryInto<Self::Deneb>
     + TryInto<Self::Electra>
+    + TryInto<Self::Fulu>
 {
     type Ref<'a>: ExecPayload<E>
         + Copy
         + From<&'a Self::Bellatrix>
         + From<&'a Self::Capella>
         + From<&'a Self::Deneb>
-        + From<&'a Self::Electra>;
+        + From<&'a Self::Electra>
+        + From<&'a Self::Fulu>;
 
     type Bellatrix: OwnedExecPayload<E>
         + Into<Self>
@@ -108,10 +110,14 @@ pub trait AbstractExecPayload<E: EthSpec>:
         + Into<Self>
         + for<'a> From<Cow<'a, ExecutionPayloadElectra<E>>>
         + TryFrom<ExecutionPayloadHeaderElectra<E>>;
+    type Fulu: OwnedExecPayload<E>
+        + Into<Self>
+        + for<'a> From<Cow<'a, ExecutionPayloadFulu<E>>>
+        + TryFrom<ExecutionPayloadHeaderFulu<E>>;
 }
 
 #[superstruct(
-    variants(Bellatrix, Capella, Deneb, Electra),
+    variants(Bellatrix, Capella, Deneb, Electra, Fulu),
     variant_attributes(
         derive(
             Debug,
@@ -157,6 +163,8 @@ pub struct FullPayload<E: EthSpec> {
     pub execution_payload: ExecutionPayloadDeneb<E>,
     #[superstruct(only(Electra), partial_getter(rename = "execution_payload_electra"))]
     pub execution_payload: ExecutionPayloadElectra<E>,
+    #[superstruct(only(Fulu), partial_getter(rename = "execution_payload_fulu"))]
+    pub execution_payload: ExecutionPayloadFulu<E>,
 }
 
 impl<E: EthSpec> From<FullPayload<E>> for ExecutionPayload<E> {
@@ -273,6 +281,9 @@ impl<E: EthSpec> ExecPayload<E> for FullPayload<E> {
             FullPayload::Electra(ref inner) => {
                 Ok(inner.execution_payload.withdrawals.tree_hash_root())
             }
+            FullPayload::Fulu(ref inner) => {
+                Ok(inner.execution_payload.withdrawals.tree_hash_root())
+            }
         }
     }
 
@@ -283,6 +294,7 @@ impl<E: EthSpec> ExecPayload<E> for FullPayload<E> {
             }
             FullPayload::Deneb(ref inner) => Ok(inner.execution_payload.blob_gas_used),
             FullPayload::Electra(ref inner) => Ok(inner.execution_payload.blob_gas_used),
+            FullPayload::Fulu(ref inner) => Ok(inner.execution_payload.blob_gas_used),
         }
     }
 
@@ -313,6 +325,7 @@ impl<E: EthSpec> FullPayload<E> {
             ForkName::Capella => Ok(FullPayloadCapella::default().into()),
             ForkName::Deneb => Ok(FullPayloadDeneb::default().into()),
             ForkName::Electra => Ok(FullPayloadElectra::default().into()),
+            ForkName::Fulu => Ok(FullPayloadFulu::default().into()),
         }
     }
 }
@@ -412,6 +425,7 @@ impl<E: EthSpec> ExecPayload<E> for FullPayloadRef<'_, E> {
             FullPayloadRef::Electra(inner) => {
                 Ok(inner.execution_payload.withdrawals.tree_hash_root())
             }
+            FullPayloadRef::Fulu(inner) => Ok(inner.execution_payload.withdrawals.tree_hash_root()),
         }
     }
 
@@ -422,6 +436,7 @@ impl<E: EthSpec> ExecPayload<E> for FullPayloadRef<'_, E> {
             }
             FullPayloadRef::Deneb(inner) => Ok(inner.execution_payload.blob_gas_used),
             FullPayloadRef::Electra(inner) => Ok(inner.execution_payload.blob_gas_used),
+            FullPayloadRef::Fulu(inner) => Ok(inner.execution_payload.blob_gas_used),
         }
     }
 
@@ -444,6 +459,7 @@ impl<E: EthSpec> AbstractExecPayload<E> for FullPayload<E> {
     type Capella = FullPayloadCapella<E>;
     type Deneb = FullPayloadDeneb<E>;
     type Electra = FullPayloadElectra<E>;
+    type Fulu = FullPayloadFulu<E>;
 }
 
 impl<E: EthSpec> From<ExecutionPayload<E>> for FullPayload<E> {
@@ -462,7 +478,7 @@ impl<E: EthSpec> TryFrom<ExecutionPayloadHeader<E>> for FullPayload<E> {
 }
 
 #[superstruct(
-    variants(Bellatrix, Capella, Deneb, Electra),
+    variants(Bellatrix, Capella, Deneb, Electra, Fulu),
     variant_attributes(
         derive(
             Debug,
@@ -507,6 +523,8 @@ pub struct BlindedPayload<E: EthSpec> {
     pub execution_payload_header: ExecutionPayloadHeaderDeneb<E>,
     #[superstruct(only(Electra), partial_getter(rename = "execution_payload_electra"))]
     pub execution_payload_header: ExecutionPayloadHeaderElectra<E>,
+    #[superstruct(only(Fulu), partial_getter(rename = "execution_payload_fulu"))]
+    pub execution_payload_header: ExecutionPayloadHeaderFulu<E>,
 }
 
 impl<'a, E: EthSpec> From<BlindedPayloadRef<'a, E>> for BlindedPayload<E> {
@@ -599,6 +617,7 @@ impl<E: EthSpec> ExecPayload<E> for BlindedPayload<E> {
             BlindedPayload::Electra(ref inner) => {
                 Ok(inner.execution_payload_header.withdrawals_root)
             }
+            BlindedPayload::Fulu(ref inner) => Ok(inner.execution_payload_header.withdrawals_root),
         }
     }
 
@@ -609,6 +628,7 @@ impl<E: EthSpec> ExecPayload<E> for BlindedPayload<E> {
             }
             BlindedPayload::Deneb(ref inner) => Ok(inner.execution_payload_header.blob_gas_used),
             BlindedPayload::Electra(ref inner) => Ok(inner.execution_payload_header.blob_gas_used),
+            BlindedPayload::Fulu(ref inner) => Ok(inner.execution_payload_header.blob_gas_used),
         }
     }
 
@@ -707,6 +727,7 @@ impl<'b, E: EthSpec> ExecPayload<E> for BlindedPayloadRef<'b, E> {
             BlindedPayloadRef::Electra(inner) => {
                 Ok(inner.execution_payload_header.withdrawals_root)
             }
+            BlindedPayloadRef::Fulu(inner) => Ok(inner.execution_payload_header.withdrawals_root),
         }
     }
 
@@ -717,6 +738,7 @@ impl<'b, E: EthSpec> ExecPayload<E> for BlindedPayloadRef<'b, E> {
             }
             BlindedPayloadRef::Deneb(inner) => Ok(inner.execution_payload_header.blob_gas_used),
             BlindedPayloadRef::Electra(inner) => Ok(inner.execution_payload_header.blob_gas_used),
+            BlindedPayloadRef::Fulu(inner) => Ok(inner.execution_payload_header.blob_gas_used),
         }
     }
 
@@ -1020,6 +1042,13 @@ impl_exec_payload_for_fork!(
     ExecutionPayloadElectra,
     Electra
 );
+impl_exec_payload_for_fork!(
+    BlindedPayloadFulu,
+    FullPayloadFulu,
+    ExecutionPayloadHeaderFulu,
+    ExecutionPayloadFulu,
+    Fulu
+);
 
 impl<E: EthSpec> AbstractExecPayload<E> for BlindedPayload<E> {
     type Ref<'a> = BlindedPayloadRef<'a, E>;
@@ -1027,6 +1056,7 @@ impl<E: EthSpec> AbstractExecPayload<E> for BlindedPayload<E> {
     type Capella = BlindedPayloadCapella<E>;
     type Deneb = BlindedPayloadDeneb<E>;
     type Electra = BlindedPayloadElectra<E>;
+    type Fulu = BlindedPayloadFulu<E>;
 }
 
 impl<E: EthSpec> From<ExecutionPayload<E>> for BlindedPayload<E> {
@@ -1063,6 +1093,11 @@ impl<E: EthSpec> From<ExecutionPayloadHeader<E>> for BlindedPayload<E> {
                     execution_payload_header,
                 })
             }
+            ExecutionPayloadHeader::Fulu(execution_payload_header) => {
+                Self::Fulu(BlindedPayloadFulu {
+                    execution_payload_header,
+                })
+            }
         }
     }
 }
@@ -1082,6 +1117,9 @@ impl<E: EthSpec> From<BlindedPayload<E>> for ExecutionPayloadHeader<E> {
             BlindedPayload::Electra(blinded_payload) => {
                 ExecutionPayloadHeader::Electra(blinded_payload.execution_payload_header)
             }
+            BlindedPayload::Fulu(blinded_payload) => {
+                ExecutionPayloadHeader::Fulu(blinded_payload.execution_payload_header)
+            }
         }
     }
 }
diff --git a/consensus/types/src/pending_partial_withdrawal.rs b/consensus/types/src/pending_partial_withdrawal.rs
index e5ace7b273..846dd97360 100644
--- a/consensus/types/src/pending_partial_withdrawal.rs
+++ b/consensus/types/src/pending_partial_withdrawal.rs
@@ -21,7 +21,7 @@ use tree_hash_derive::TreeHash;
 )]
 pub struct PendingPartialWithdrawal {
     #[serde(with = "serde_utils::quoted_u64")]
-    pub index: u64,
+    pub validator_index: u64,
     #[serde(with = "serde_utils::quoted_u64")]
     pub amount: u64,
     pub withdrawable_epoch: Epoch,
diff --git a/consensus/types/src/preset.rs b/consensus/types/src/preset.rs
index b469b7b777..707d2d4697 100644
--- a/consensus/types/src/preset.rs
+++ b/consensus/types/src/preset.rs
@@ -205,8 +205,6 @@ impl CapellaPreset {
 #[derive(Debug, PartialEq, Clone, Serialize, Deserialize)]
 #[serde(rename_all = "UPPERCASE")]
 pub struct DenebPreset {
-    #[serde(with = "serde_utils::quoted_u64")]
-    pub max_blobs_per_block: u64,
     #[serde(with = "serde_utils::quoted_u64")]
     pub max_blob_commitments_per_block: u64,
     #[serde(with = "serde_utils::quoted_u64")]
@@ -216,7 +214,6 @@ pub struct DenebPreset {
 impl DenebPreset {
     pub fn from_chain_spec<E: EthSpec>(_spec: &ChainSpec) -> Self {
         Self {
-            max_blobs_per_block: E::max_blobs_per_block() as u64,
             max_blob_commitments_per_block: E::max_blob_commitments_per_block() as u64,
             field_elements_per_blob: E::field_elements_per_blob() as u64,
         }
@@ -237,7 +234,7 @@ pub struct ElectraPreset {
     #[serde(with = "serde_utils::quoted_u64")]
     pub max_pending_partials_per_withdrawals_sweep: u64,
     #[serde(with = "serde_utils::quoted_u64")]
-    pub pending_balance_deposits_limit: u64,
+    pub pending_deposits_limit: u64,
     #[serde(with = "serde_utils::quoted_u64")]
     pub pending_partial_withdrawals_limit: u64,
     #[serde(with = "serde_utils::quoted_u64")]
@@ -263,7 +260,7 @@ impl ElectraPreset {
             whistleblower_reward_quotient_electra: spec.whistleblower_reward_quotient_electra,
             max_pending_partials_per_withdrawals_sweep: spec
                 .max_pending_partials_per_withdrawals_sweep,
-            pending_balance_deposits_limit: E::pending_deposits_limit() as u64,
+            pending_deposits_limit: E::pending_deposits_limit() as u64,
             pending_partial_withdrawals_limit: E::pending_partial_withdrawals_limit() as u64,
             pending_consolidations_limit: E::pending_consolidations_limit() as u64,
             max_consolidation_requests_per_payload: E::max_consolidation_requests_per_payload()
@@ -278,7 +275,7 @@ impl ElectraPreset {
 
 #[derive(Debug, PartialEq, Clone, Serialize, Deserialize)]
 #[serde(rename_all = "UPPERCASE")]
-pub struct Eip7594Preset {
+pub struct FuluPreset {
     #[serde(with = "serde_utils::quoted_u64")]
     pub field_elements_per_cell: u64,
     #[serde(with = "serde_utils::quoted_u64")]
@@ -287,7 +284,7 @@ pub struct Eip7594Preset {
     pub kzg_commitments_inclusion_proof_depth: u64,
 }
 
-impl Eip7594Preset {
+impl FuluPreset {
     pub fn from_chain_spec<E: EthSpec>(_spec: &ChainSpec) -> Self {
         Self {
             field_elements_per_cell: E::field_elements_per_cell() as u64,
@@ -343,8 +340,8 @@ mod test {
         let electra: ElectraPreset = preset_from_file(&preset_name, "electra.yaml");
         assert_eq!(electra, ElectraPreset::from_chain_spec::<E>(&spec));
 
-        let eip7594: Eip7594Preset = preset_from_file(&preset_name, "eip7594.yaml");
-        assert_eq!(eip7594, Eip7594Preset::from_chain_spec::<E>(&spec));
+        let fulu: FuluPreset = preset_from_file(&preset_name, "fulu.yaml");
+        assert_eq!(fulu, FuluPreset::from_chain_spec::<E>(&spec));
     }
 
     #[test]
diff --git a/consensus/types/src/runtime_fixed_vector.rs b/consensus/types/src/runtime_fixed_vector.rs
new file mode 100644
index 0000000000..2b08b7bf70
--- /dev/null
+++ b/consensus/types/src/runtime_fixed_vector.rs
@@ -0,0 +1,81 @@
+//! Emulates a fixed size array but with the length set at runtime.
+//!
+//! The length of the list cannot be changed once it is set.
+
+#[derive(Clone, Debug)]
+pub struct RuntimeFixedVector<T> {
+    vec: Vec<T>,
+    len: usize,
+}
+
+impl<T: Clone + Default> RuntimeFixedVector<T> {
+    pub fn new(vec: Vec<T>) -> Self {
+        let len = vec.len();
+        Self { vec, len }
+    }
+
+    pub fn to_vec(&self) -> Vec<T> {
+        self.vec.clone()
+    }
+
+    pub fn as_slice(&self) -> &[T] {
+        self.vec.as_slice()
+    }
+
+    #[allow(clippy::len_without_is_empty)]
+    pub fn len(&self) -> usize {
+        self.len
+    }
+
+    pub fn into_vec(self) -> Vec<T> {
+        self.vec
+    }
+
+    pub fn default(max_len: usize) -> Self {
+        Self {
+            vec: vec![T::default(); max_len],
+            len: max_len,
+        }
+    }
+
+    pub fn take(&mut self) -> Self {
+        let new = std::mem::take(&mut self.vec);
+        *self = Self::new(vec![T::default(); self.len]);
+        Self {
+            vec: new,
+            len: self.len,
+        }
+    }
+}
+
+impl<T> std::ops::Deref for RuntimeFixedVector<T> {
+    type Target = [T];
+
+    fn deref(&self) -> &[T] {
+        &self.vec[..]
+    }
+}
+
+impl<T> std::ops::DerefMut for RuntimeFixedVector<T> {
+    fn deref_mut(&mut self) -> &mut [T] {
+        &mut self.vec[..]
+    }
+}
+
+impl<T> IntoIterator for RuntimeFixedVector<T> {
+    type Item = T;
+    type IntoIter = std::vec::IntoIter<T>;
+
+    fn into_iter(self) -> Self::IntoIter {
+        self.vec.into_iter()
+    }
+}
+
+impl<'a, T> IntoIterator for &'a RuntimeFixedVector<T> {
+    type Item = &'a T;
+    type IntoIter = std::slice::Iter<'a, T>;
+
+    fn into_iter(self) -> Self::IntoIter {
+        self.vec.iter()
+    }
+}
diff --git a/consensus/types/src/runtime_var_list.rs b/consensus/types/src/runtime_var_list.rs
index 8290876fa1..857073b3b8 100644
--- a/consensus/types/src/runtime_var_list.rs
+++ b/consensus/types/src/runtime_var_list.rs
@@ -2,7 +2,7 @@ use derivative::Derivative;
 use serde::{Deserialize, Serialize};
 use ssz::Decode;
 use ssz_types::Error;
-use std::ops::{Deref, DerefMut, Index, IndexMut};
+use std::ops::{Deref, Index, IndexMut};
 use std::slice::SliceIndex;
 
 /// Emulates a SSZ `List`.
@@ -10,6 +10,8 @@ use std::slice::SliceIndex;
 /// An ordered, heap-allocated, variable-length, homogeneous collection of `T`, with no more than
 /// `max_len` values.
 ///
+/// To ensure there are no inconsistent states, we do not allow any mutating operation if `max_len` is not set.
+///
 /// ## Example
 ///
 /// ```
@@ -35,6 +37,7 @@ use std::slice::SliceIndex;
 ///
 /// // Push a value to if it _does_ exceed the maximum.
 /// assert!(long.push(6).is_err());
+///
 /// ```
 #[derive(Debug, Clone, Serialize, Deserialize, Derivative)]
 #[derivative(PartialEq, Eq, Hash(bound = "T: std::hash::Hash"))]
@@ -65,7 +68,7 @@ impl<T> RuntimeVariableList<T> {
         Self { vec, max_len }
     }
 
-    /// Create an empty list.
+    /// Create an empty list with the given `max_len`.
     pub fn empty(max_len: usize) -> Self {
         Self {
             vec: vec![],
@@ -77,6 +80,10 @@ impl<T> RuntimeVariableList<T> {
         self.vec.as_slice()
     }
 
+    pub fn as_mut_slice(&mut self) -> &mut [T] {
+        self.vec.as_mut_slice()
+    }
+
     /// Returns the number of values presently in `self`.
     pub fn len(&self) -> usize {
         self.vec.len()
@@ -88,6 +95,8 @@ impl<T> RuntimeVariableList<T> {
     }
 
     /// Returns the type-level maximum length.
+    ///
+    /// Returns `None` if self is uninitialized with a max_len.
     pub fn max_len(&self) -> usize {
         self.max_len
     }
@@ -169,12 +178,6 @@ impl<T> Deref for RuntimeVariableList<T> {
     }
 }
 
-impl<T> DerefMut for RuntimeVariableList<T> {
-    fn deref_mut(&mut self) -> &mut [T] {
-        &mut self.vec[..]
-    }
-}
-
 impl<'a, T> IntoIterator for &'a RuntimeVariableList<T> {
     type Item = &'a T;
     type IntoIter = std::slice::Iter<'a, T>;
diff --git a/consensus/types/src/signed_beacon_block.rs b/consensus/types/src/signed_beacon_block.rs
index bb5e1ea34b..d9bf9bf55d 100644
--- a/consensus/types/src/signed_beacon_block.rs
+++ b/consensus/types/src/signed_beacon_block.rs
@@ -38,7 +38,7 @@ impl From<SignedBeaconBlockHash> for Hash256 {
 
 /// A `BeaconBlock` and a signature from its proposer.
 #[superstruct(
-    variants(Base, Altair, Bellatrix, Capella, Deneb, Electra),
+    variants(Base, Altair, Bellatrix, Capella, Deneb, Electra, Fulu),
     variant_attributes(
         derive(
             Debug,
@@ -81,6 +81,8 @@ pub struct SignedBeaconBlock<E: EthSpec, Payload: AbstractExecPayload<E> = FullP
     pub message: BeaconBlockDeneb<E, Payload>,
     #[superstruct(only(Electra), partial_getter(rename = "message_electra"))]
     pub message: BeaconBlockElectra<E, Payload>,
+    #[superstruct(only(Fulu), partial_getter(rename = "message_fulu"))]
+    pub message: BeaconBlockFulu<E, Payload>,
     pub signature: Signature,
 }
 
@@ -163,6 +165,9 @@ impl<E: EthSpec, Payload: AbstractExecPayload<E>> SignedBeaconBlock<E, Payload>
             BeaconBlock::Electra(message) => {
                 SignedBeaconBlock::Electra(SignedBeaconBlockElectra { message, signature })
             }
+            BeaconBlock::Fulu(message) => {
+                SignedBeaconBlock::Fulu(SignedBeaconBlockFulu { message, signature })
+            }
         }
     }
 
@@ -570,6 +575,64 @@ impl<E: EthSpec> SignedBeaconBlockElectra<E, BlindedPayload<E>> {
     }
 }
 
+impl<E: EthSpec> SignedBeaconBlockFulu<E, BlindedPayload<E>> {
+    pub fn into_full_block(
+        self,
+        execution_payload: ExecutionPayloadFulu<E>,
+    ) -> SignedBeaconBlockFulu<E, FullPayload<E>> {
+        let SignedBeaconBlockFulu {
+            message:
+                BeaconBlockFulu {
+                    slot,
+                    proposer_index,
+                    parent_root,
+                    state_root,
+                    body:
+                        BeaconBlockBodyFulu {
+                            randao_reveal,
+                            eth1_data,
+                            graffiti,
+                            proposer_slashings,
+                            attester_slashings,
+                            attestations,
+                            deposits,
+                            voluntary_exits,
+                            sync_aggregate,
+                            execution_payload: BlindedPayloadFulu { .. },
+                            bls_to_execution_changes,
+                            blob_kzg_commitments,
+                            execution_requests,
+                        },
+                },
+            signature,
+        } = self;
+        SignedBeaconBlockFulu {
+            message: BeaconBlockFulu {
+                slot,
+                proposer_index,
+                parent_root,
+                state_root,
+                body: BeaconBlockBodyFulu {
+                    randao_reveal,
+                    eth1_data,
+                    graffiti,
+                    proposer_slashings,
+                    attester_slashings,
+                    attestations,
+                    deposits,
+                    voluntary_exits,
+                    sync_aggregate,
+                    execution_payload: FullPayloadFulu { execution_payload },
+                    bls_to_execution_changes,
+                    blob_kzg_commitments,
+                    execution_requests,
+                },
+            },
+            signature,
+        }
+    }
+}
+
 impl<E: EthSpec> SignedBeaconBlock<E, BlindedPayload<E>> {
     pub fn try_into_full_block(
         self,
@@ -590,12 +653,16 @@ impl<E: EthSpec> SignedBeaconBlock<E, BlindedPayload<E>> {
             (SignedBeaconBlock::Electra(block), Some(ExecutionPayload::Electra(payload))) => {
                 SignedBeaconBlock::Electra(block.into_full_block(payload))
             }
+            (SignedBeaconBlock::Fulu(block), Some(ExecutionPayload::Fulu(payload))) => {
+                SignedBeaconBlock::Fulu(block.into_full_block(payload))
+            }
             // avoid wildcard matching forks so that compiler will
             // direct us here when a new fork has been added
             (SignedBeaconBlock::Bellatrix(_), _) => return None,
             (SignedBeaconBlock::Capella(_), _) => return None,
             (SignedBeaconBlock::Deneb(_), _) => return None,
             (SignedBeaconBlock::Electra(_), _) => return None,
+            (SignedBeaconBlock::Fulu(_), _) => return None,
         };
         Some(full_block)
     }
@@ -741,6 +808,9 @@ pub mod ssz_tagged_signed_beacon_block {
                 ForkName::Electra => Ok(SignedBeaconBlock::Electra(
                     SignedBeaconBlockElectra::from_ssz_bytes(body)?,
                 )),
+                ForkName::Fulu => Ok(SignedBeaconBlock::Fulu(
+                    SignedBeaconBlockFulu::from_ssz_bytes(body)?,
+                )),
             }
         }
     }
@@ -841,8 +911,9 @@ mod test {
             ),
             SignedBeaconBlock::from_block(
                 BeaconBlock::Electra(BeaconBlockElectra::empty(spec)),
-                sig,
+                sig.clone(),
             ),
+            SignedBeaconBlock::from_block(BeaconBlock::Fulu(BeaconBlockFulu::empty(spec)), sig),
         ];
 
         for block in blocks {
diff --git a/consensus/types/src/subnet_id.rs b/consensus/types/src/subnet_id.rs
index 187b070d29..7a5357c6cc 100644
--- a/consensus/types/src/subnet_id.rs
+++ b/consensus/types/src/subnet_id.rs
@@ -1,4 +1,5 @@
 //! Identifies each shard by an integer identifier.
+use crate::SingleAttestation;
 use crate::{AttestationRef, ChainSpec, CommitteeIndex, EthSpec, Slot};
 use alloy_primitives::{bytes::Buf, U256};
 use safe_arith::{ArithError, SafeArith};
@@ -57,6 +58,21 @@ impl SubnetId {
         )
     }
 
+    /// Compute the subnet for an attestation where each slot in the
+    /// attestation epoch contains `committee_count_per_slot` committees.
+    pub fn compute_subnet_for_single_attestation<E: EthSpec>(
+        attestation: &SingleAttestation,
+        committee_count_per_slot: u64,
+        spec: &ChainSpec,
+    ) -> Result<SubnetId, ArithError> {
+        Self::compute_subnet::<E>(
+            attestation.data.slot,
+            attestation.committee_index,
+            committee_count_per_slot,
+            spec,
+        )
+    }
+
     /// Compute the subnet for an attestation with `attestation.data.slot == slot` and
     /// `attestation.data.index == committee_index` where each slot in the attestation epoch
     /// contains `committee_count_at_slot` committees.
diff --git a/consensus/types/src/validator.rs b/consensus/types/src/validator.rs
index 222b9292a2..5aed90d2c1 100644
--- a/consensus/types/src/validator.rs
+++ b/consensus/types/src/validator.rs
@@ -56,7 +56,7 @@ impl Validator {
         };
 
         let max_effective_balance = validator.get_max_effective_balance(spec, fork_name);
-        // safe math is unnecessary here since the spec.effecive_balance_increment is never <= 0
+        // safe math is unnecessary here since the spec.effective_balance_increment is never <= 0
         validator.effective_balance = std::cmp::min(
             amount - (amount % spec.effective_balance_increment),
             max_effective_balance,
@@ -195,7 +195,7 @@ impl Validator {
     /// Returns `true` if the validator is fully withdrawable at some epoch.
     ///
     /// Calls the correct function depending on the provided `fork_name`.
-    pub fn is_fully_withdrawable_at(
+    pub fn is_fully_withdrawable_validator(
         &self,
         balance: u64,
         epoch: Epoch,
@@ -203,14 +203,14 @@ impl Validator {
         current_fork: ForkName,
     ) -> bool {
         if current_fork.electra_enabled() {
-            self.is_fully_withdrawable_at_electra(balance, epoch, spec)
+            self.is_fully_withdrawable_validator_electra(balance, epoch, spec)
         } else {
-            self.is_fully_withdrawable_at_capella(balance, epoch, spec)
+            self.is_fully_withdrawable_validator_capella(balance, epoch, spec)
         }
     }
 
     /// Returns `true` if the validator is fully withdrawable at some epoch.
-    fn is_fully_withdrawable_at_capella(
+    fn is_fully_withdrawable_validator_capella(
         &self,
         balance: u64,
         epoch: Epoch,
@@ -222,7 +222,7 @@ impl Validator {
     /// Returns `true` if the validator is fully withdrawable at some epoch.
     ///
     /// Modified in electra as part of EIP 7251.
-    fn is_fully_withdrawable_at_electra(
+    fn is_fully_withdrawable_validator_electra(
         &self,
         balance: u64,
         epoch: Epoch,
diff --git a/crypto/kzg/Cargo.toml b/crypto/kzg/Cargo.toml
index bfe0f19cd0..e26fe59413 100644
--- a/crypto/kzg/Cargo.toml
+++ b/crypto/kzg/Cargo.toml
@@ -8,6 +8,12 @@ edition = "2021"
 [dependencies]
 arbitrary = { workspace = true }
 c-kzg = { workspace = true }
+# Required to maintain the pin from https://github.com/sigp/lighthouse/pull/6608
+crate_crypto_internal_eth_kzg_bls12_381 = { workspace = true }
+crate_crypto_internal_eth_kzg_erasure_codes = { workspace = true }
+crate_crypto_internal_eth_kzg_maybe_rayon = { workspace = true }
+crate_crypto_internal_eth_kzg_polynomial = { workspace = true }
+crate_crypto_kzg_multi_open_fk20 = { workspace = true }
 derivative = { workspace = true }
 ethereum_hashing = { workspace = true }
 ethereum_serde_utils = { workspace = true }
diff --git a/crypto/kzg/src/lib.rs b/crypto/kzg/src/lib.rs
index 348ed785af..2a5c6e47f5 100644
--- a/crypto/kzg/src/lib.rs
+++ b/crypto/kzg/src/lib.rs
@@ -21,6 +21,9 @@ pub use rust_eth_kzg::{
     Cell, CellIndex as CellID, CellRef, TrustedSetup as PeerDASTrustedSetup,
 };
 
+// Note: `spec.number_of_columns` is a config and should match `CELLS_PER_EXT_BLOB` - however this
+// is a constant in the KZG library - be aware that overriding `number_of_columns` will break KZG
+// operations.
 pub type CellsAndKzgProofs = ([Cell; CELLS_PER_EXT_BLOB], [KzgProof; CELLS_PER_EXT_BLOB]);
 
 pub type KzgBlobRef<'a> = &'a [u8; BYTES_PER_BLOB];
diff --git a/database_manager/src/cli.rs b/database_manager/src/cli.rs
index 4246a51f89..9db807df2c 100644
--- a/database_manager/src/cli.rs
+++ b/database_manager/src/cli.rs
@@ -57,6 +57,15 @@ pub struct DatabaseManager {
     )]
     pub blobs_dir: Option<PathBuf>,
 
+    #[clap(
+        long,
+        value_name = "DATABASE",
+        help = "Set the database backend to be used by the beacon node.",
+        display_order = 0,
+        default_value_t = store::config::DatabaseBackend::LevelDb
+    )]
+    pub backend: store::config::DatabaseBackend,
+
     #[clap(
         long,
         global = true,
diff --git a/database_manager/src/lib.rs b/database_manager/src/lib.rs
index fc15e98616..bed90df9df 100644
--- a/database_manager/src/lib.rs
+++ b/database_manager/src/lib.rs
@@ -16,10 +16,12 @@ use slog::{info, warn, Logger};
 use std::fs;
 use std::io::Write;
 use std::path::PathBuf;
+use store::KeyValueStore;
 use store::{
+    database::interface::BeaconNodeBackend,
     errors::Error,
     metadata::{SchemaVersion, CURRENT_SCHEMA_VERSION},
-    DBColumn, HotColdDB, KeyValueStore, LevelDB,
+    DBColumn, HotColdDB,
 };
 use strum::{EnumString, EnumVariantNames};
 use types::{BeaconState, EthSpec, Slot};
@@ -40,7 +42,7 @@ fn parse_client_config<E: EthSpec>(
         .clone_from(&database_manager_config.blobs_dir);
     client_config.store.blob_prune_margin_epochs = database_manager_config.blob_prune_margin_epochs;
     client_config.store.hierarchy_config = database_manager_config.hierarchy_exponents.clone();
-
+    client_config.store.backend = database_manager_config.backend;
     Ok(client_config)
 }
 
@@ -55,7 +57,7 @@ pub fn display_db_version<E: EthSpec>(
     let blobs_path = client_config.get_blobs_db_path();
 
     let mut version = CURRENT_SCHEMA_VERSION;
-    HotColdDB::<E, LevelDB<E>, LevelDB<E>>::open(
+    HotColdDB::<E, BeaconNodeBackend<E>, BeaconNodeBackend<E>>::open(
         &hot_path,
         &cold_path,
         &blobs_path,
@@ -145,11 +147,14 @@ pub fn inspect_db<E: EthSpec>(
     let mut num_keys = 0;
 
     let sub_db = if inspect_config.freezer {
-        LevelDB::<E>::open(&cold_path).map_err(|e| format!("Unable to open freezer DB: {e:?}"))?
+        BeaconNodeBackend::<E>::open(&client_config.store, &cold_path)
+            .map_err(|e| format!("Unable to open freezer DB: {e:?}"))?
     } else if inspect_config.blobs_db {
-        LevelDB::<E>::open(&blobs_path).map_err(|e| format!("Unable to open blobs DB: {e:?}"))?
+        BeaconNodeBackend::<E>::open(&client_config.store, &blobs_path)
+            .map_err(|e| format!("Unable to open blobs DB: {e:?}"))?
     } else {
-        LevelDB::<E>::open(&hot_path).map_err(|e| format!("Unable to open hot DB: {e:?}"))?
+        BeaconNodeBackend::<E>::open(&client_config.store, &hot_path)
+            .map_err(|e| format!("Unable to open hot DB: {e:?}"))?
     };
 
     let skip = inspect_config.skip.unwrap_or(0);
@@ -263,11 +268,20 @@ pub fn compact_db<E: EthSpec>(
     let column = compact_config.column;
 
     let (sub_db, db_name) = if compact_config.freezer {
-        (LevelDB::<E>::open(&cold_path)?, "freezer_db")
+        (
+            BeaconNodeBackend::<E>::open(&client_config.store, &cold_path)?,
+            "freezer_db",
+        )
     } else if compact_config.blobs_db {
-        (LevelDB::<E>::open(&blobs_path)?, "blobs_db")
+        (
+            BeaconNodeBackend::<E>::open(&client_config.store, &blobs_path)?,
+            "blobs_db",
+        )
     } else {
-        (LevelDB::<E>::open(&hot_path)?, "hot_db")
+        (
+            BeaconNodeBackend::<E>::open(&client_config.store, &hot_path)?,
+            "hot_db",
+        )
     };
     info!(
         log,
@@ -303,7 +317,7 @@ pub fn migrate_db<E: EthSpec>(
 
     let mut from = CURRENT_SCHEMA_VERSION;
     let to = migrate_config.to;
-    let db = HotColdDB::<E, LevelDB<E>, LevelDB<E>>::open(
+    let db = HotColdDB::<E, BeaconNodeBackend<E>, BeaconNodeBackend<E>>::open(
         &hot_path,
         &cold_path,
         &blobs_path,
@@ -343,7 +357,7 @@ pub fn prune_payloads<E: EthSpec>(
     let cold_path = client_config.get_freezer_db_path();
     let blobs_path = client_config.get_blobs_db_path();
 
-    let db = HotColdDB::<E, LevelDB<E>, LevelDB<E>>::open(
+    let db = HotColdDB::<E, BeaconNodeBackend<E>, BeaconNodeBackend<E>>::open(
         &hot_path,
         &cold_path,
         &blobs_path,
@@ -369,7 +383,7 @@ pub fn prune_blobs<E: EthSpec>(
     let cold_path = client_config.get_freezer_db_path();
     let blobs_path = client_config.get_blobs_db_path();
 
-    let db = HotColdDB::<E, LevelDB<E>, LevelDB<E>>::open(
+    let db = HotColdDB::<E, BeaconNodeBackend<E>, BeaconNodeBackend<E>>::open(
         &hot_path,
         &cold_path,
         &blobs_path,
@@ -406,7 +420,7 @@ pub fn prune_states<E: EthSpec>(
     let cold_path = client_config.get_freezer_db_path();
     let blobs_path = client_config.get_blobs_db_path();
 
-    let db = HotColdDB::<E, LevelDB<E>, LevelDB<E>>::open(
+    let db = HotColdDB::<E, BeaconNodeBackend<E>, BeaconNodeBackend<E>>::open(
         &hot_path,
         &cold_path,
         &blobs_path,
diff --git a/lcli/Dockerfile b/lcli/Dockerfile
index d2cb6f6f14..67bc290112 100644
--- a/lcli/Dockerfile
+++ b/lcli/Dockerfile
@@ -1,7 +1,7 @@
 # `lcli` requires the full project to be in scope, so this should be built either:
 #  - from the `lighthouse` dir with the command: `docker build -f ./lcli/Dockerflie .`
 #  - from the current directory with the command: `docker build -f ./Dockerfile ../`
-FROM rust:1.80.0-bullseye AS builder
+FROM rust:1.84.0-bullseye AS builder
 RUN apt-get update && apt-get -y upgrade && apt-get install -y cmake libclang-dev
 COPY . lighthouse
 ARG FEATURES
diff --git a/lcli/src/mock_el.rs b/lcli/src/mock_el.rs
index 8d3220b1df..2e2c27a2db 100644
--- a/lcli/src/mock_el.rs
+++ b/lcli/src/mock_el.rs
@@ -9,6 +9,7 @@ use execution_layer::{
 };
 use std::net::Ipv4Addr;
 use std::path::PathBuf;
+use std::sync::Arc;
 use types::*;
 
 pub fn run<E: EthSpec>(mut env: Environment<E>, matches: &ArgMatches) -> Result<(), String> {
@@ -19,9 +20,10 @@ pub fn run<E: EthSpec>(mut env: Environment<E>, matches: &ArgMatches) -> Result<
     let shanghai_time = parse_required(matches, "shanghai-time")?;
     let cancun_time = parse_optional(matches, "cancun-time")?;
     let prague_time = parse_optional(matches, "prague-time")?;
+    let osaka_time = parse_optional(matches, "osaka-time")?;
 
     let handle = env.core_context().executor.handle().unwrap();
-    let spec = &E::default_spec();
+    let spec = Arc::new(E::default_spec());
     let jwt_key = JwtKey::from_slice(&DEFAULT_JWT_SECRET).unwrap();
     std::fs::write(jwt_path, hex::encode(DEFAULT_JWT_SECRET)).unwrap();
 
@@ -37,9 +39,10 @@ pub fn run<E: EthSpec>(mut env: Environment<E>, matches: &ArgMatches) -> Result<
         shanghai_time: Some(shanghai_time),
         cancun_time,
         prague_time,
+        osaka_time,
     };
     let kzg = None;
-    let server: MockServer<E> = MockServer::new_with_config(&handle, config, kzg);
+    let server: MockServer<E> = MockServer::new_with_config(&handle, config, spec, kzg);
 
     if all_payloads_valid {
         eprintln!(
diff --git a/lcli/src/transition_blocks.rs b/lcli/src/transition_blocks.rs
index 94d95a0d1c..ecfa04fc81 100644
--- a/lcli/src/transition_blocks.rs
+++ b/lcli/src/transition_blocks.rs
@@ -223,7 +223,7 @@ pub fn run<E: EthSpec>(
             .update_tree_hash_cache()
             .map_err(|e| format!("Unable to build THC: {:?}", e))?;
 
-        if state_root_opt.map_or(false, |expected| expected != state_root) {
+        if state_root_opt.is_some_and(|expected| expected != state_root) {
             return Err(format!(
                 "State root mismatch! Expected {}, computed {}",
                 state_root_opt.unwrap(),
@@ -331,7 +331,7 @@ fn do_transition<E: EthSpec>(
             .map_err(|e| format!("Unable to build tree hash cache: {:?}", e))?;
         debug!("Initial tree hash: {:?}", t.elapsed());
 
-        if state_root_opt.map_or(false, |expected| expected != state_root) {
+        if state_root_opt.is_some_and(|expected| expected != state_root) {
             return Err(format!(
                 "State root mismatch! Expected {}, computed {}",
                 state_root_opt.unwrap(),
diff --git a/lighthouse/Cargo.toml b/lighthouse/Cargo.toml
index eda9a2ebf2..c95735d41c 100644
--- a/lighthouse/Cargo.toml
+++ b/lighthouse/Cargo.toml
@@ -4,10 +4,10 @@ version = "6.0.1"
 authors = ["Sigma Prime <contact@sigmaprime.io>"]
 edition = { workspace = true }
 autotests = false
-rust-version = "1.80.0"
+rust-version = "1.83.0"
 
 [features]
-default = ["slasher-lmdb"]
+default = ["slasher-lmdb", "beacon-node-leveldb"]
 # Writes debugging .ssz files to /tmp during block processing.
 write_ssz_files = ["beacon_node/write_ssz_files"]
 # Compiles the BLS crypto code so that the binary is portable across machines.
@@ -24,6 +24,11 @@ slasher-mdbx = ["slasher/mdbx"]
 slasher-lmdb = ["slasher/lmdb"]
 # Support slasher redb backend.
 slasher-redb = ["slasher/redb"]
+# Supports beacon node leveldb backend.
+beacon-node-leveldb = ["store/leveldb"]
+# Supports beacon node redb backend.
+beacon-node-redb = ["store/redb"]
+
 # Deprecated. This is now enabled by default on non windows targets.
 jemalloc = []
 
@@ -56,6 +61,7 @@ serde_json = { workspace = true }
 serde_yaml = { workspace = true }
 slasher = { workspace = true }
 slog = { workspace = true }
+store = { workspace = true }
 task_executor = { workspace = true }
 types = { workspace = true }
 unused_port = { workspace = true }
diff --git a/lighthouse/src/main.rs b/lighthouse/src/main.rs
index 43c5e1107c..dd7401d49e 100644
--- a/lighthouse/src/main.rs
+++ b/lighthouse/src/main.rs
@@ -66,11 +66,15 @@ fn bls_hardware_acceleration() -> bool {
     return std::arch::is_aarch64_feature_detected!("neon");
 }
 
-fn allocator_name() -> &'static str {
-    if cfg!(target_os = "windows") {
-        "system"
-    } else {
-        "jemalloc"
+fn allocator_name() -> String {
+    #[cfg(target_os = "windows")]
+    {
+        "system".to_string()
+    }
+    #[cfg(not(target_os = "windows"))]
+    match malloc_utils::jemalloc::page_size() {
+        Ok(page_size) => format!("jemalloc ({}K)", page_size / 1024),
+        Err(e) => format!("jemalloc (error: {e:?})"),
     }
 }
 
diff --git a/lighthouse/tests/beacon_node.rs b/lighthouse/tests/beacon_node.rs
index 88e05dfa12..1063a80ff4 100644
--- a/lighthouse/tests/beacon_node.rs
+++ b/lighthouse/tests/beacon_node.rs
@@ -1,11 +1,12 @@
-use beacon_node::ClientConfig as Config;
-
 use crate::exec::{CommandLineTestExec, CompletedTest};
 use beacon_node::beacon_chain::chain_config::{
     DisallowedReOrgOffsets, DEFAULT_RE_ORG_CUTOFF_DENOMINATOR, DEFAULT_RE_ORG_HEAD_THRESHOLD,
     DEFAULT_RE_ORG_MAX_EPOCHS_SINCE_FINALIZATION,
 };
-use beacon_node::beacon_chain::graffiti_calculator::GraffitiOrigin;
+use beacon_node::{
+    beacon_chain::graffiti_calculator::GraffitiOrigin,
+    beacon_chain::store::config::DatabaseBackend as BeaconNodeBackend, ClientConfig as Config,
+};
 use beacon_processor::BeaconProcessorConfig;
 use eth1::Eth1Endpoint;
 use lighthouse_network::PeerId;
@@ -2691,3 +2692,13 @@ fn genesis_state_url_value() {
             assert_eq!(config.genesis_state_url_timeout, Duration::from_secs(42));
         });
 }
+
+#[test]
+fn beacon_node_backend_override() {
+    CommandLineTest::new()
+        .flag("beacon-node-backend", Some("leveldb"))
+        .run_with_zero_port()
+        .with_config(|config| {
+            assert_eq!(config.store.backend, BeaconNodeBackend::LevelDb);
+        });
+}
diff --git a/lighthouse/tests/validator_client.rs b/lighthouse/tests/validator_client.rs
index c5b303e4d1..1945399c86 100644
--- a/lighthouse/tests/validator_client.rs
+++ b/lighthouse/tests/validator_client.rs
@@ -345,7 +345,7 @@ fn http_store_keystore_passwords_in_secrets_dir_present() {
 }
 
 #[test]
-fn http_token_path_flag() {
+fn http_token_path_flag_present() {
     let dir = TempDir::new().expect("Unable to create temporary directory");
     CommandLineTest::new()
         .flag("http", None)
@@ -359,6 +359,19 @@ fn http_token_path_flag() {
         });
 }
 
+#[test]
+fn http_token_path_default() {
+    CommandLineTest::new()
+        .flag("http", None)
+        .run()
+        .with_config(|config| {
+            assert_eq!(
+                config.http_api.http_token_path,
+                config.validator_dir.join("api-token.txt")
+            );
+        });
+}
+
 // Tests for Metrics flags.
 #[test]
 fn metrics_flag() {
diff --git a/scripts/local_testnet/network_params_das.yaml b/scripts/local_testnet/network_params_das.yaml
index ab2f07a24e..030aa2b820 100644
--- a/scripts/local_testnet/network_params_das.yaml
+++ b/scripts/local_testnet/network_params_das.yaml
@@ -3,6 +3,7 @@ participants:
     cl_image: lighthouse:local
     cl_extra_params:
       - --subscribe-all-data-column-subnets
+      - --subscribe-all-subnets
       - --target-peers=3
     count: 2
   - cl_type: lighthouse
@@ -11,11 +12,14 @@ participants:
       - --target-peers=3
     count: 2
 network_params:
-  eip7594_fork_epoch: 0
+  electra_fork_epoch: 1
+  fulu_fork_epoch: 2
   seconds_per_slot: 6
 snooper_enabled: false
 global_log_level: debug
 additional_services:
   - dora
-  - goomy_blob
+  - spamoor_blob
   - prometheus_grafana
+dora_params:
+  image: ethpandaops/dora:fulu-support
\ No newline at end of file
diff --git a/slasher/src/database.rs b/slasher/src/database.rs
index 20b4a33771..e2b49dca29 100644
--- a/slasher/src/database.rs
+++ b/slasher/src/database.rs
@@ -406,7 +406,7 @@ impl<E: EthSpec> SlasherDB<E> {
     ) -> Result<(), Error> {
         // Don't update maximum if new target is less than or equal to previous. In the case of
         // no previous we *do* want to update.
-        if previous_max_target.map_or(false, |prev_max| max_target <= prev_max) {
+        if previous_max_target.is_some_and(|prev_max| max_target <= prev_max) {
             return Ok(());
         }
 
diff --git a/testing/ef_tests/Makefile b/testing/ef_tests/Makefile
index d5f4997bb7..7b507f8c50 100644
--- a/testing/ef_tests/Makefile
+++ b/testing/ef_tests/Makefile
@@ -1,4 +1,4 @@
-TESTS_TAG := v1.5.0-alpha.8
+TESTS_TAG := v1.5.0-beta.1
 TESTS = general minimal mainnet
 TARBALLS = $(patsubst %,%-$(TESTS_TAG).tar.gz,$(TESTS))
 
diff --git a/testing/ef_tests/check_all_files_accessed.py b/testing/ef_tests/check_all_files_accessed.py
index dacca204c1..02a01555b4 100755
--- a/testing/ef_tests/check_all_files_accessed.py
+++ b/testing/ef_tests/check_all_files_accessed.py
@@ -35,6 +35,8 @@ excluded_paths = [
     "tests/.*/.*/ssz_static/LightClientStore",
     # LightClientSnapshot
     "tests/.*/.*/ssz_static/LightClientSnapshot",
+    # LightClientDataCollection
+    "tests/minimal/.*/light_client/data_collection",
     # One of the EF researchers likes to pack the tarballs on a Mac
     ".*\\.DS_Store.*",
     # More Mac weirdness.
@@ -47,7 +49,10 @@ excluded_paths = [
     "bls12-381-tests/hash_to_G2",
     "tests/.*/eip6110",
     "tests/.*/whisk",
-    "tests/.*/eip7594",
+    # TODO(electra): SingleAttestation tests are waiting on Eitan's PR
+    "tests/.*/electra/ssz_static/SingleAttestation",
+    "tests/.*/fulu/ssz_static/SingleAttestation",
+    "tests/.*/fulu/ssz_static/MatrixEntry",
 ]
 
 
diff --git a/testing/ef_tests/src/cases.rs b/testing/ef_tests/src/cases.rs
index 63274ee0c0..4a202ee3d2 100644
--- a/testing/ef_tests/src/cases.rs
+++ b/testing/ef_tests/src/cases.rs
@@ -13,12 +13,13 @@ mod bls_fast_aggregate_verify;
 mod bls_sign_msg;
 mod bls_verify_msg;
 mod common;
+mod compute_columns_for_custody_groups;
 mod epoch_processing;
 mod fork;
 mod fork_choice;
 mod genesis_initialization;
 mod genesis_validity;
-mod get_custody_columns;
+mod get_custody_groups;
 mod kzg_blob_to_kzg_commitment;
 mod kzg_compute_blob_kzg_proof;
 mod kzg_compute_cells_and_kzg_proofs;
@@ -49,11 +50,12 @@ pub use bls_fast_aggregate_verify::*;
 pub use bls_sign_msg::*;
 pub use bls_verify_msg::*;
 pub use common::SszStaticType;
+pub use compute_columns_for_custody_groups::*;
 pub use epoch_processing::*;
 pub use fork::ForkTest;
 pub use genesis_initialization::*;
 pub use genesis_validity::*;
-pub use get_custody_columns::*;
+pub use get_custody_groups::*;
 pub use kzg_blob_to_kzg_commitment::*;
 pub use kzg_compute_blob_kzg_proof::*;
 pub use kzg_compute_cells_and_kzg_proofs::*;
@@ -74,15 +76,44 @@ pub use ssz_generic::*;
 pub use ssz_static::*;
 pub use transition::TransitionTest;
 
-#[derive(Debug, PartialEq)]
+/// Used for running feature tests for future forks that have not yet been added to `ForkName`.
+/// This runs tests in the directory named by the feature instead of the fork name. This has been
+/// the pattern used in the `consensus-spec-tests` repository:
+/// `consensus-spec-tests/tests/general/[feature_name]/[runner_name].`
+/// e.g. consensus-spec-tests/tests/general/peerdas/ssz_static
+///
+/// The feature tests can be run with one of the following methods:
+/// 1. `handler.run_for_feature(feature_name)` for new tests that are not on existing fork, i.e. a
+///     new handler. This will be temporary and the test will need to be updated to use
+///     `handle.run()` once the feature is incorporated into a fork.
+/// 2. `handler.run()` for tests that are already on existing forks, but with new test vectors for
+///     the feature. In this case the `handler.is_enabled_for_feature` will need to be implemented
+///     to return `true` for the feature in order for the feature test vector to be tested.
+#[derive(Debug, PartialEq, Clone, Copy)]
 pub enum FeatureName {
-    Eip7594,
+    // TODO(fulu): to be removed once we start using Fulu types for test vectors.
+    // Existing SSZ types for PeerDAS (Fulu) are the same as Electra, so the test vectors get
+    // loaded as Electra types (default serde behaviour for untagged enums).
+    Fulu,
+}
+
+impl FeatureName {
+    pub fn list_all() -> Vec<FeatureName> {
+        vec![FeatureName::Fulu]
+    }
+
+    /// `ForkName` to use when running the feature tests.
+    pub fn fork_name(&self) -> ForkName {
+        match self {
+            FeatureName::Fulu => ForkName::Electra,
+        }
+    }
 }
 
 impl Display for FeatureName {
     fn fmt(&self, f: &mut Formatter<'_>) -> std::fmt::Result {
         match self {
-            FeatureName::Eip7594 => f.write_str("eip7594"),
+            FeatureName::Fulu => f.write_str("fulu"),
         }
     }
 }
@@ -107,11 +138,13 @@ pub trait Case: Debug + Sync {
         true
     }
 
-    /// Whether or not this test exists for the given `feature_name`.
+    /// Whether or not this test exists for the given `feature_name`. This is intended to be used
+    /// for features that have not been added to a fork yet, and there is usually a separate folder
+    /// for the feature in the `consensus-spec-tests` repository.
     ///
-    /// Returns `true` by default.
+    /// Returns `false` by default.
     fn is_enabled_for_feature(_feature_name: FeatureName) -> bool {
-        true
+        false
     }
 
     /// Execute a test and return the result.
diff --git a/testing/ef_tests/src/cases/common.rs b/testing/ef_tests/src/cases/common.rs
index e16f5b257f..62f834820f 100644
--- a/testing/ef_tests/src/cases/common.rs
+++ b/testing/ef_tests/src/cases/common.rs
@@ -66,6 +66,7 @@ pub fn previous_fork(fork_name: ForkName) -> ForkName {
         ForkName::Capella => ForkName::Bellatrix,
         ForkName::Deneb => ForkName::Capella,
         ForkName::Electra => ForkName::Deneb,
+        ForkName::Fulu => ForkName::Electra,
     }
 }
 
diff --git a/testing/ef_tests/src/cases/compute_columns_for_custody_groups.rs b/testing/ef_tests/src/cases/compute_columns_for_custody_groups.rs
new file mode 100644
index 0000000000..8a6330d399
--- /dev/null
+++ b/testing/ef_tests/src/cases/compute_columns_for_custody_groups.rs
@@ -0,0 +1,43 @@
+use super::*;
+use serde::Deserialize;
+use std::marker::PhantomData;
+use types::data_column_custody_group::{compute_columns_for_custody_group, CustodyIndex};
+
+#[derive(Debug, Clone, Deserialize)]
+#[serde(bound = "E: EthSpec", deny_unknown_fields)]
+pub struct ComputeColumnsForCustodyGroups<E: EthSpec> {
+    /// The custody group index.
+    pub custody_group: CustodyIndex,
+    /// The list of resulting custody columns.
+    pub result: Vec<u64>,
+    #[serde(skip)]
+    _phantom: PhantomData<E>,
+}
+
+impl<E: EthSpec> LoadCase for ComputeColumnsForCustodyGroups<E> {
+    fn load_from_dir(path: &Path, _fork_name: ForkName) -> Result<Self, Error> {
+        decode::yaml_decode_file(path.join("meta.yaml").as_path())
+    }
+}
+
+impl<E: EthSpec> Case for ComputeColumnsForCustodyGroups<E> {
+    fn is_enabled_for_fork(fork_name: ForkName) -> bool {
+        fork_name.fulu_enabled()
+    }
+
+    fn result(&self, _case_index: usize, _fork_name: ForkName) -> Result<(), Error> {
+        let spec = E::default_spec();
+        let computed_columns = compute_columns_for_custody_group(self.custody_group, &spec)
+            .expect("should compute custody columns from group")
+            .collect::<Vec<_>>();
+
+        let expected = &self.result;
+        if computed_columns == *expected {
+            Ok(())
+        } else {
+            Err(Error::NotEqual(format!(
+                "Got {computed_columns:?}\nExpected {expected:?}"
+            )))
+        }
+    }
+}
diff --git a/testing/ef_tests/src/cases/epoch_processing.rs b/testing/ef_tests/src/cases/epoch_processing.rs
index c1adf10770..e05225c171 100644
--- a/testing/ef_tests/src/cases/epoch_processing.rs
+++ b/testing/ef_tests/src/cases/epoch_processing.rs
@@ -100,47 +100,35 @@ type_name!(ParticipationFlagUpdates, "participation_flag_updates");
 
 impl<E: EthSpec> EpochTransition<E> for JustificationAndFinalization {
     fn run(state: &mut BeaconState<E>, spec: &ChainSpec) -> Result<(), EpochProcessingError> {
-        match state {
-            BeaconState::Base(_) => {
-                let mut validator_statuses = base::ValidatorStatuses::new(state, spec)?;
-                validator_statuses.process_attestations(state)?;
-                let justification_and_finalization_state =
-                    base::process_justification_and_finalization(
-                        state,
-                        &validator_statuses.total_balances,
-                        spec,
-                    )?;
-                justification_and_finalization_state.apply_changes_to_state(state);
-                Ok(())
-            }
-            BeaconState::Altair(_)
-            | BeaconState::Bellatrix(_)
-            | BeaconState::Capella(_)
-            | BeaconState::Deneb(_)
-            | BeaconState::Electra(_) => {
-                initialize_progressive_balances_cache(state, spec)?;
-                let justification_and_finalization_state =
-                    altair::process_justification_and_finalization(state)?;
-                justification_and_finalization_state.apply_changes_to_state(state);
-                Ok(())
-            }
+        if state.fork_name_unchecked().altair_enabled() {
+            initialize_progressive_balances_cache(state, spec)?;
+            let justification_and_finalization_state =
+                altair::process_justification_and_finalization(state)?;
+            justification_and_finalization_state.apply_changes_to_state(state);
+            Ok(())
+        } else {
+            let mut validator_statuses = base::ValidatorStatuses::new(state, spec)?;
+            validator_statuses.process_attestations(state)?;
+            let justification_and_finalization_state =
+                base::process_justification_and_finalization(
+                    state,
+                    &validator_statuses.total_balances,
+                    spec,
+                )?;
+            justification_and_finalization_state.apply_changes_to_state(state);
+            Ok(())
         }
     }
 }
 
 impl<E: EthSpec> EpochTransition<E> for RewardsAndPenalties {
     fn run(state: &mut BeaconState<E>, spec: &ChainSpec) -> Result<(), EpochProcessingError> {
-        match state {
-            BeaconState::Base(_) => {
-                let mut validator_statuses = base::ValidatorStatuses::new(state, spec)?;
-                validator_statuses.process_attestations(state)?;
-                base::process_rewards_and_penalties(state, &validator_statuses, spec)
-            }
-            BeaconState::Altair(_)
-            | BeaconState::Bellatrix(_)
-            | BeaconState::Capella(_)
-            | BeaconState::Deneb(_)
-            | BeaconState::Electra(_) => altair::process_rewards_and_penalties_slow(state, spec),
+        if state.fork_name_unchecked().altair_enabled() {
+            altair::process_rewards_and_penalties_slow(state, spec)
+        } else {
+            let mut validator_statuses = base::ValidatorStatuses::new(state, spec)?;
+            validator_statuses.process_attestations(state)?;
+            base::process_rewards_and_penalties(state, &validator_statuses, spec)
         }
     }
 }
@@ -159,24 +147,17 @@ impl<E: EthSpec> EpochTransition<E> for RegistryUpdates {
 
 impl<E: EthSpec> EpochTransition<E> for Slashings {
     fn run(state: &mut BeaconState<E>, spec: &ChainSpec) -> Result<(), EpochProcessingError> {
-        match state {
-            BeaconState::Base(_) => {
-                let mut validator_statuses = base::ValidatorStatuses::new(state, spec)?;
-                validator_statuses.process_attestations(state)?;
-                process_slashings(
-                    state,
-                    validator_statuses.total_balances.current_epoch(),
-                    spec,
-                )?;
-            }
-            BeaconState::Altair(_)
-            | BeaconState::Bellatrix(_)
-            | BeaconState::Capella(_)
-            | BeaconState::Deneb(_)
-            | BeaconState::Electra(_) => {
-                process_slashings_slow(state, spec)?;
-            }
-        };
+        if state.fork_name_unchecked().altair_enabled() {
+            process_slashings_slow(state, spec)?;
+        } else {
+            let mut validator_statuses = base::ValidatorStatuses::new(state, spec)?;
+            validator_statuses.process_attestations(state)?;
+            process_slashings(
+                state,
+                validator_statuses.total_balances.current_epoch(),
+                spec,
+            )?;
+        }
         Ok(())
     }
 }
@@ -251,11 +232,10 @@ impl<E: EthSpec> EpochTransition<E> for HistoricalRootsUpdate {
 
 impl<E: EthSpec> EpochTransition<E> for HistoricalSummariesUpdate {
     fn run(state: &mut BeaconState<E>, _spec: &ChainSpec) -> Result<(), EpochProcessingError> {
-        match state {
-            BeaconState::Capella(_) | BeaconState::Deneb(_) | BeaconState::Electra(_) => {
-                process_historical_summaries_update(state)
-            }
-            _ => Ok(()),
+        if state.fork_name_unchecked().capella_enabled() {
+            process_historical_summaries_update(state)
+        } else {
+            Ok(())
         }
     }
 }
@@ -272,39 +252,30 @@ impl<E: EthSpec> EpochTransition<E> for ParticipationRecordUpdates {
 
 impl<E: EthSpec> EpochTransition<E> for SyncCommitteeUpdates {
     fn run(state: &mut BeaconState<E>, spec: &ChainSpec) -> Result<(), EpochProcessingError> {
-        match state {
-            BeaconState::Base(_) => Ok(()),
-            BeaconState::Altair(_)
-            | BeaconState::Bellatrix(_)
-            | BeaconState::Capella(_)
-            | BeaconState::Deneb(_)
-            | BeaconState::Electra(_) => altair::process_sync_committee_updates(state, spec),
+        if state.fork_name_unchecked().altair_enabled() {
+            altair::process_sync_committee_updates(state, spec)
+        } else {
+            Ok(())
         }
     }
 }
 
 impl<E: EthSpec> EpochTransition<E> for InactivityUpdates {
     fn run(state: &mut BeaconState<E>, spec: &ChainSpec) -> Result<(), EpochProcessingError> {
-        match state {
-            BeaconState::Base(_) => Ok(()),
-            BeaconState::Altair(_)
-            | BeaconState::Bellatrix(_)
-            | BeaconState::Capella(_)
-            | BeaconState::Deneb(_)
-            | BeaconState::Electra(_) => altair::process_inactivity_updates_slow(state, spec),
+        if state.fork_name_unchecked().altair_enabled() {
+            altair::process_inactivity_updates_slow(state, spec)
+        } else {
+            Ok(())
         }
     }
 }
 
 impl<E: EthSpec> EpochTransition<E> for ParticipationFlagUpdates {
     fn run(state: &mut BeaconState<E>, _: &ChainSpec) -> Result<(), EpochProcessingError> {
-        match state {
-            BeaconState::Base(_) => Ok(()),
-            BeaconState::Altair(_)
-            | BeaconState::Bellatrix(_)
-            | BeaconState::Capella(_)
-            | BeaconState::Deneb(_)
-            | BeaconState::Electra(_) => altair::process_participation_flag_updates(state),
+        if state.fork_name_unchecked().altair_enabled() {
+            altair::process_participation_flag_updates(state)
+        } else {
+            Ok(())
         }
     }
 }
diff --git a/testing/ef_tests/src/cases/fork.rs b/testing/ef_tests/src/cases/fork.rs
index 132cfb4c0a..85301e22f6 100644
--- a/testing/ef_tests/src/cases/fork.rs
+++ b/testing/ef_tests/src/cases/fork.rs
@@ -5,7 +5,7 @@ use crate::decode::{ssz_decode_state, yaml_decode_file};
 use serde::Deserialize;
 use state_processing::upgrade::{
     upgrade_to_altair, upgrade_to_bellatrix, upgrade_to_capella, upgrade_to_deneb,
-    upgrade_to_electra,
+    upgrade_to_electra, upgrade_to_fulu,
 };
 use types::BeaconState;
 
@@ -69,6 +69,7 @@ impl<E: EthSpec> Case for ForkTest<E> {
             ForkName::Capella => upgrade_to_capella(&mut result_state, spec).map(|_| result_state),
             ForkName::Deneb => upgrade_to_deneb(&mut result_state, spec).map(|_| result_state),
             ForkName::Electra => upgrade_to_electra(&mut result_state, spec).map(|_| result_state),
+            ForkName::Fulu => upgrade_to_fulu(&mut result_state, spec).map(|_| result_state),
         };
 
         compare_beacon_state_results_without_caches(&mut result, &mut expected)
diff --git a/testing/ef_tests/src/cases/fork_choice.rs b/testing/ef_tests/src/cases/fork_choice.rs
index 427bcf5e9c..a1c74389a7 100644
--- a/testing/ef_tests/src/cases/fork_choice.rs
+++ b/testing/ef_tests/src/cases/fork_choice.rs
@@ -523,7 +523,7 @@ impl<E: EthSpec> Tester<E> {
                 || Ok(()),
             ))?
             .map(|avail: AvailabilityProcessingStatus| avail.try_into());
-        let success = blob_success && result.as_ref().map_or(false, |inner| inner.is_ok());
+        let success = blob_success && result.as_ref().is_ok_and(|inner| inner.is_ok());
         if success != valid {
             return Err(Error::DidntFail(format!(
                 "block with root {} was valid={} whilst test expects valid={}. result: {:?}",
diff --git a/testing/ef_tests/src/cases/genesis_initialization.rs b/testing/ef_tests/src/cases/genesis_initialization.rs
index 11402c75e6..210e18f781 100644
--- a/testing/ef_tests/src/cases/genesis_initialization.rs
+++ b/testing/ef_tests/src/cases/genesis_initialization.rs
@@ -66,8 +66,7 @@ impl<E: EthSpec> LoadCase for GenesisInitialization<E> {
 
 impl<E: EthSpec> Case for GenesisInitialization<E> {
     fn is_enabled_for_fork(fork_name: ForkName) -> bool {
-        // Altair genesis and later requires real crypto.
-        fork_name == ForkName::Base || cfg!(not(feature = "fake_crypto"))
+        fork_name == ForkName::Base
     }
 
     fn result(&self, _case_index: usize, fork_name: ForkName) -> Result<(), Error> {
diff --git a/testing/ef_tests/src/cases/genesis_validity.rs b/testing/ef_tests/src/cases/genesis_validity.rs
index e977fa3d63..8fb9f2fbdc 100644
--- a/testing/ef_tests/src/cases/genesis_validity.rs
+++ b/testing/ef_tests/src/cases/genesis_validity.rs
@@ -39,6 +39,10 @@ impl<E: EthSpec> LoadCase for GenesisValidity<E> {
 }
 
 impl<E: EthSpec> Case for GenesisValidity<E> {
+    fn is_enabled_for_fork(fork_name: ForkName) -> bool {
+        fork_name == ForkName::Base
+    }
+
     fn result(&self, _case_index: usize, fork_name: ForkName) -> Result<(), Error> {
         let spec = &testing_spec::<E>(fork_name);
 
diff --git a/testing/ef_tests/src/cases/get_custody_columns.rs b/testing/ef_tests/src/cases/get_custody_groups.rs
similarity index 59%
rename from testing/ef_tests/src/cases/get_custody_columns.rs
rename to testing/ef_tests/src/cases/get_custody_groups.rs
index 9665f87730..1c1294305f 100644
--- a/testing/ef_tests/src/cases/get_custody_columns.rs
+++ b/testing/ef_tests/src/cases/get_custody_groups.rs
@@ -2,37 +2,42 @@ use super::*;
 use alloy_primitives::U256;
 use serde::Deserialize;
 use std::marker::PhantomData;
-use types::DataColumnSubnetId;
+use types::data_column_custody_group::get_custody_groups;
 
 #[derive(Debug, Clone, Deserialize)]
 #[serde(bound = "E: EthSpec", deny_unknown_fields)]
-pub struct GetCustodyColumns<E: EthSpec> {
+pub struct GetCustodyGroups<E: EthSpec> {
+    /// The NodeID input.
     pub node_id: String,
-    pub custody_subnet_count: u64,
+    /// The count of custody groups.
+    pub custody_group_count: u64,
+    /// The list of resulting custody groups.
     pub result: Vec<u64>,
     #[serde(skip)]
     _phantom: PhantomData<E>,
 }
 
-impl<E: EthSpec> LoadCase for GetCustodyColumns<E> {
+impl<E: EthSpec> LoadCase for GetCustodyGroups<E> {
     fn load_from_dir(path: &Path, _fork_name: ForkName) -> Result<Self, Error> {
         decode::yaml_decode_file(path.join("meta.yaml").as_path())
     }
 }
 
-impl<E: EthSpec> Case for GetCustodyColumns<E> {
+impl<E: EthSpec> Case for GetCustodyGroups<E> {
+    fn is_enabled_for_fork(fork_name: ForkName) -> bool {
+        fork_name.fulu_enabled()
+    }
+
     fn result(&self, _case_index: usize, _fork_name: ForkName) -> Result<(), Error> {
         let spec = E::default_spec();
         let node_id = U256::from_str_radix(&self.node_id, 10)
             .map_err(|e| Error::FailedToParseTest(format!("{e:?}")))?;
         let raw_node_id = node_id.to_be_bytes::<32>();
-        let computed = DataColumnSubnetId::compute_custody_columns::<E>(
-            raw_node_id,
-            self.custody_subnet_count,
-            &spec,
-        )
-        .expect("should compute custody columns")
-        .collect::<Vec<_>>();
+        let mut computed = get_custody_groups(raw_node_id, self.custody_group_count, &spec)
+            .map(|set| set.into_iter().collect::<Vec<_>>())
+            .expect("should compute custody groups");
+        computed.sort();
+
         let expected = &self.result;
         if computed == *expected {
             Ok(())
diff --git a/testing/ef_tests/src/cases/kzg_blob_to_kzg_commitment.rs b/testing/ef_tests/src/cases/kzg_blob_to_kzg_commitment.rs
index fa16a5fcb7..feb9a4ff5c 100644
--- a/testing/ef_tests/src/cases/kzg_blob_to_kzg_commitment.rs
+++ b/testing/ef_tests/src/cases/kzg_blob_to_kzg_commitment.rs
@@ -31,10 +31,6 @@ impl<E: EthSpec> Case for KZGBlobToKZGCommitment<E> {
         fork_name == ForkName::Deneb
     }
 
-    fn is_enabled_for_feature(feature_name: FeatureName) -> bool {
-        feature_name != FeatureName::Eip7594
-    }
-
     fn result(&self, _case_index: usize, _fork_name: ForkName) -> Result<(), Error> {
         let kzg = get_kzg();
         let commitment = parse_blob::<E>(&self.input.blob).and_then(|blob| {
diff --git a/testing/ef_tests/src/cases/kzg_compute_blob_kzg_proof.rs b/testing/ef_tests/src/cases/kzg_compute_blob_kzg_proof.rs
index 694013e251..4aadc37af2 100644
--- a/testing/ef_tests/src/cases/kzg_compute_blob_kzg_proof.rs
+++ b/testing/ef_tests/src/cases/kzg_compute_blob_kzg_proof.rs
@@ -32,10 +32,6 @@ impl<E: EthSpec> Case for KZGComputeBlobKZGProof<E> {
         fork_name == ForkName::Deneb
     }
 
-    fn is_enabled_for_feature(feature_name: FeatureName) -> bool {
-        feature_name != FeatureName::Eip7594
-    }
-
     fn result(&self, _case_index: usize, _fork_name: ForkName) -> Result<(), Error> {
         let parse_input = |input: &KZGComputeBlobKZGProofInput| -> Result<_, Error> {
             let blob = parse_blob::<E>(&input.blob)?;
diff --git a/testing/ef_tests/src/cases/kzg_compute_cells_and_kzg_proofs.rs b/testing/ef_tests/src/cases/kzg_compute_cells_and_kzg_proofs.rs
index 2a9f8ceeef..6ab9a8db65 100644
--- a/testing/ef_tests/src/cases/kzg_compute_cells_and_kzg_proofs.rs
+++ b/testing/ef_tests/src/cases/kzg_compute_cells_and_kzg_proofs.rs
@@ -27,7 +27,7 @@ impl<E: EthSpec> LoadCase for KZGComputeCellsAndKZGProofs<E> {
 
 impl<E: EthSpec> Case for KZGComputeCellsAndKZGProofs<E> {
     fn is_enabled_for_fork(fork_name: ForkName) -> bool {
-        fork_name == ForkName::Deneb
+        fork_name.fulu_enabled()
     }
 
     fn result(&self, _case_index: usize, _fork_name: ForkName) -> Result<(), Error> {
diff --git a/testing/ef_tests/src/cases/kzg_compute_kzg_proof.rs b/testing/ef_tests/src/cases/kzg_compute_kzg_proof.rs
index 6f53038f28..4a47fe35eb 100644
--- a/testing/ef_tests/src/cases/kzg_compute_kzg_proof.rs
+++ b/testing/ef_tests/src/cases/kzg_compute_kzg_proof.rs
@@ -39,10 +39,6 @@ impl<E: EthSpec> Case for KZGComputeKZGProof<E> {
         fork_name == ForkName::Deneb
     }
 
-    fn is_enabled_for_feature(feature_name: FeatureName) -> bool {
-        feature_name != FeatureName::Eip7594
-    }
-
     fn result(&self, _case_index: usize, _fork_name: ForkName) -> Result<(), Error> {
         let parse_input = |input: &KZGComputeKZGProofInput| -> Result<_, Error> {
             let blob = parse_blob::<E>(&input.blob)?;
diff --git a/testing/ef_tests/src/cases/kzg_recover_cells_and_kzg_proofs.rs b/testing/ef_tests/src/cases/kzg_recover_cells_and_kzg_proofs.rs
index 10cc866fbe..732cb54f31 100644
--- a/testing/ef_tests/src/cases/kzg_recover_cells_and_kzg_proofs.rs
+++ b/testing/ef_tests/src/cases/kzg_recover_cells_and_kzg_proofs.rs
@@ -28,7 +28,7 @@ impl<E: EthSpec> LoadCase for KZGRecoverCellsAndKZGProofs<E> {
 
 impl<E: EthSpec> Case for KZGRecoverCellsAndKZGProofs<E> {
     fn is_enabled_for_fork(fork_name: ForkName) -> bool {
-        fork_name == ForkName::Deneb
+        fork_name.fulu_enabled()
     }
 
     fn result(&self, _case_index: usize, _fork_name: ForkName) -> Result<(), Error> {
diff --git a/testing/ef_tests/src/cases/kzg_verify_blob_kzg_proof.rs b/testing/ef_tests/src/cases/kzg_verify_blob_kzg_proof.rs
index 3dc955bdcc..66f50d534b 100644
--- a/testing/ef_tests/src/cases/kzg_verify_blob_kzg_proof.rs
+++ b/testing/ef_tests/src/cases/kzg_verify_blob_kzg_proof.rs
@@ -116,10 +116,6 @@ impl<E: EthSpec> Case for KZGVerifyBlobKZGProof<E> {
         fork_name == ForkName::Deneb
     }
 
-    fn is_enabled_for_feature(feature_name: FeatureName) -> bool {
-        feature_name != FeatureName::Eip7594
-    }
-
     fn result(&self, _case_index: usize, _fork_name: ForkName) -> Result<(), Error> {
         let parse_input = |input: &KZGVerifyBlobKZGProofInput| -> Result<(Blob<E>, KzgCommitment, KzgProof), Error> {
             let blob = parse_blob::<E>(&input.blob)?;
diff --git a/testing/ef_tests/src/cases/kzg_verify_blob_kzg_proof_batch.rs b/testing/ef_tests/src/cases/kzg_verify_blob_kzg_proof_batch.rs
index 80cd0a2849..efd4158806 100644
--- a/testing/ef_tests/src/cases/kzg_verify_blob_kzg_proof_batch.rs
+++ b/testing/ef_tests/src/cases/kzg_verify_blob_kzg_proof_batch.rs
@@ -33,10 +33,6 @@ impl<E: EthSpec> Case for KZGVerifyBlobKZGProofBatch<E> {
         fork_name == ForkName::Deneb
     }
 
-    fn is_enabled_for_feature(feature_name: FeatureName) -> bool {
-        feature_name != FeatureName::Eip7594
-    }
-
     fn result(&self, _case_index: usize, _fork_name: ForkName) -> Result<(), Error> {
         let parse_input = |input: &KZGVerifyBlobKZGProofBatchInput| -> Result<_, Error> {
             let blobs = input
diff --git a/testing/ef_tests/src/cases/kzg_verify_cell_kzg_proof_batch.rs b/testing/ef_tests/src/cases/kzg_verify_cell_kzg_proof_batch.rs
index 5887d764ca..e3edc0df0a 100644
--- a/testing/ef_tests/src/cases/kzg_verify_cell_kzg_proof_batch.rs
+++ b/testing/ef_tests/src/cases/kzg_verify_cell_kzg_proof_batch.rs
@@ -30,7 +30,7 @@ impl<E: EthSpec> LoadCase for KZGVerifyCellKZGProofBatch<E> {
 
 impl<E: EthSpec> Case for KZGVerifyCellKZGProofBatch<E> {
     fn is_enabled_for_fork(fork_name: ForkName) -> bool {
-        fork_name == ForkName::Deneb
+        fork_name.fulu_enabled()
     }
 
     fn result(&self, _case_index: usize, _fork_name: ForkName) -> Result<(), Error> {
diff --git a/testing/ef_tests/src/cases/kzg_verify_kzg_proof.rs b/testing/ef_tests/src/cases/kzg_verify_kzg_proof.rs
index ed7583dbd0..07df05a6ac 100644
--- a/testing/ef_tests/src/cases/kzg_verify_kzg_proof.rs
+++ b/testing/ef_tests/src/cases/kzg_verify_kzg_proof.rs
@@ -33,10 +33,6 @@ impl<E: EthSpec> Case for KZGVerifyKZGProof<E> {
         fork_name == ForkName::Deneb
     }
 
-    fn is_enabled_for_feature(feature_name: FeatureName) -> bool {
-        feature_name != FeatureName::Eip7594
-    }
-
     fn result(&self, _case_index: usize, _fork_name: ForkName) -> Result<(), Error> {
         let parse_input = |input: &KZGVerifyKZGProofInput| -> Result<_, Error> {
             let commitment = parse_commitment(&input.commitment)?;
diff --git a/testing/ef_tests/src/cases/merkle_proof_validity.rs b/testing/ef_tests/src/cases/merkle_proof_validity.rs
index 49c0719784..109d2cc796 100644
--- a/testing/ef_tests/src/cases/merkle_proof_validity.rs
+++ b/testing/ef_tests/src/cases/merkle_proof_validity.rs
@@ -4,7 +4,7 @@ use serde::Deserialize;
 use tree_hash::Hash256;
 use types::{
     light_client_update, BeaconBlockBody, BeaconBlockBodyCapella, BeaconBlockBodyDeneb,
-    BeaconBlockBodyElectra, BeaconState, FixedVector, FullPayload, Unsigned,
+    BeaconBlockBodyElectra, BeaconBlockBodyFulu, BeaconState, FixedVector, FullPayload, Unsigned,
 };
 
 #[derive(Debug, Clone, Deserialize)]
@@ -131,6 +131,9 @@ impl<E: EthSpec> LoadCase for KzgInclusionMerkleProofValidity<E> {
                 ssz_decode_file::<BeaconBlockBodyElectra<E>>(&path.join("object.ssz_snappy"))?
                     .into()
             }
+            ForkName::Fulu => {
+                ssz_decode_file::<BeaconBlockBodyFulu<E>>(&path.join("object.ssz_snappy"))?.into()
+            }
         };
         let merkle_proof = yaml_decode_file(&path.join("proof.yaml"))?;
         // Metadata does not exist in these tests but it is left like this just in case.
@@ -246,6 +249,9 @@ impl<E: EthSpec> LoadCase for BeaconBlockBodyMerkleProofValidity<E> {
                 ssz_decode_file::<BeaconBlockBodyElectra<E>>(&path.join("object.ssz_snappy"))?
                     .into()
             }
+            ForkName::Fulu => {
+                ssz_decode_file::<BeaconBlockBodyFulu<E>>(&path.join("object.ssz_snappy"))?.into()
+            }
         };
         let merkle_proof = yaml_decode_file(&path.join("proof.yaml"))?;
         // Metadata does not exist in these tests but it is left like this just in case.
diff --git a/testing/ef_tests/src/cases/operations.rs b/testing/ef_tests/src/cases/operations.rs
index 54ca52447f..adb5bee768 100644
--- a/testing/ef_tests/src/cases/operations.rs
+++ b/testing/ef_tests/src/cases/operations.rs
@@ -98,29 +98,24 @@ impl<E: EthSpec> Operation<E> for Attestation<E> {
     ) -> Result<(), BlockProcessingError> {
         initialize_epoch_cache(state, spec)?;
         let mut ctxt = ConsensusContext::new(state.slot());
-        match state {
-            BeaconState::Base(_) => base::process_attestations(
+        if state.fork_name_unchecked().altair_enabled() {
+            initialize_progressive_balances_cache(state, spec)?;
+            altair_deneb::process_attestation(
+                state,
+                self.to_ref(),
+                0,
+                &mut ctxt,
+                VerifySignatures::True,
+                spec,
+            )
+        } else {
+            base::process_attestations(
                 state,
                 [self.clone().to_ref()].into_iter(),
                 VerifySignatures::True,
                 &mut ctxt,
                 spec,
-            ),
-            BeaconState::Altair(_)
-            | BeaconState::Bellatrix(_)
-            | BeaconState::Capella(_)
-            | BeaconState::Deneb(_)
-            | BeaconState::Electra(_) => {
-                initialize_progressive_balances_cache(state, spec)?;
-                altair_deneb::process_attestation(
-                    state,
-                    self.to_ref(),
-                    0,
-                    &mut ctxt,
-                    VerifySignatures::True,
-                    spec,
-                )
-            }
+            )
         }
     }
 }
@@ -131,14 +126,11 @@ impl<E: EthSpec> Operation<E> for AttesterSlashing<E> {
     }
 
     fn decode(path: &Path, fork_name: ForkName, _spec: &ChainSpec) -> Result<Self, Error> {
-        Ok(match fork_name {
-            ForkName::Base
-            | ForkName::Altair
-            | ForkName::Bellatrix
-            | ForkName::Capella
-            | ForkName::Deneb => Self::Base(ssz_decode_file(path)?),
-            ForkName::Electra => Self::Electra(ssz_decode_file(path)?),
-        })
+        if fork_name.electra_enabled() {
+            Ok(Self::Electra(ssz_decode_file(path)?))
+        } else {
+            Ok(Self::Base(ssz_decode_file(path)?))
+        }
     }
 
     fn apply_to(
@@ -308,6 +300,7 @@ impl<E: EthSpec> Operation<E> for BeaconBlockBody<E, FullPayload<E>> {
                 ForkName::Capella => BeaconBlockBody::Capella(<_>::from_ssz_bytes(bytes)?),
                 ForkName::Deneb => BeaconBlockBody::Deneb(<_>::from_ssz_bytes(bytes)?),
                 ForkName::Electra => BeaconBlockBody::Electra(<_>::from_ssz_bytes(bytes)?),
+                ForkName::Fulu => BeaconBlockBody::Fulu(<_>::from_ssz_bytes(bytes)?),
                 _ => panic!(),
             })
         })
@@ -322,7 +315,7 @@ impl<E: EthSpec> Operation<E> for BeaconBlockBody<E, FullPayload<E>> {
         let valid = extra
             .execution_metadata
             .as_ref()
-            .map_or(false, |e| e.execution_valid);
+            .is_some_and(|e| e.execution_valid);
         if valid {
             process_execution_payload::<E, FullPayload<E>>(state, self.to_ref(), spec)
         } else {
@@ -363,6 +356,10 @@ impl<E: EthSpec> Operation<E> for BeaconBlockBody<E, BlindedPayload<E>> {
                     let inner = <BeaconBlockBodyElectra<E, FullPayload<E>>>::from_ssz_bytes(bytes)?;
                     BeaconBlockBody::Electra(inner.clone_as_blinded())
                 }
+                ForkName::Fulu => {
+                    let inner = <BeaconBlockBodyElectra<E, FullPayload<E>>>::from_ssz_bytes(bytes)?;
+                    BeaconBlockBody::Electra(inner.clone_as_blinded())
+                }
                 _ => panic!(),
             })
         })
@@ -377,7 +374,7 @@ impl<E: EthSpec> Operation<E> for BeaconBlockBody<E, BlindedPayload<E>> {
         let valid = extra
             .execution_metadata
             .as_ref()
-            .map_or(false, |e| e.execution_valid);
+            .is_some_and(|e| e.execution_valid);
         if valid {
             process_execution_payload::<E, BlindedPayload<E>>(state, self.to_ref(), spec)
         } else {
diff --git a/testing/ef_tests/src/cases/transition.rs b/testing/ef_tests/src/cases/transition.rs
index dc5029d53e..6d037dae87 100644
--- a/testing/ef_tests/src/cases/transition.rs
+++ b/testing/ef_tests/src/cases/transition.rs
@@ -60,6 +60,14 @@ impl<E: EthSpec> LoadCase for TransitionTest<E> {
                 spec.deneb_fork_epoch = Some(Epoch::new(0));
                 spec.electra_fork_epoch = Some(metadata.fork_epoch);
             }
+            ForkName::Fulu => {
+                spec.altair_fork_epoch = Some(Epoch::new(0));
+                spec.bellatrix_fork_epoch = Some(Epoch::new(0));
+                spec.capella_fork_epoch = Some(Epoch::new(0));
+                spec.deneb_fork_epoch = Some(Epoch::new(0));
+                spec.electra_fork_epoch = Some(Epoch::new(0));
+                spec.fulu_fork_epoch = Some(metadata.fork_epoch);
+            }
         }
 
         // Load blocks
diff --git a/testing/ef_tests/src/decode.rs b/testing/ef_tests/src/decode.rs
index 757b9bf3c4..eb88ac6af1 100644
--- a/testing/ef_tests/src/decode.rs
+++ b/testing/ef_tests/src/decode.rs
@@ -28,7 +28,7 @@ pub fn log_file_access<P: AsRef<Path>>(file_accessed: P) {
 
     writeln!(&mut file, "{:?}", file_accessed.as_ref()).expect("should write to file");
 
-    file.unlock().expect("unable to unlock file");
+    fs2::FileExt::unlock(&file).expect("unable to unlock file");
 }
 
 pub fn yaml_decode<T: serde::de::DeserializeOwned>(string: &str) -> Result<T, Error> {
diff --git a/testing/ef_tests/src/handler.rs b/testing/ef_tests/src/handler.rs
index f4a09de32c..d1ddd6a48f 100644
--- a/testing/ef_tests/src/handler.rs
+++ b/testing/ef_tests/src/handler.rs
@@ -7,9 +7,6 @@ use std::marker::PhantomData;
 use std::path::PathBuf;
 use types::{BeaconState, EthSpec, ForkName};
 
-const EIP7594_FORK: ForkName = ForkName::Deneb;
-const EIP7594_TESTS: [&str; 4] = ["ssz_static", "merkle_proof", "networking", "kzg"];
-
 pub trait Handler {
     type Case: Case + LoadCase;
 
@@ -24,7 +21,7 @@ pub trait Handler {
     // Add forks here to exclude them from EF spec testing. Helpful for adding future or
     // unspecified forks.
     fn disabled_forks(&self) -> Vec<ForkName> {
-        vec![]
+        vec![ForkName::Fulu]
     }
 
     fn is_enabled_for_fork(&self, fork_name: ForkName) -> bool {
@@ -39,13 +36,16 @@ pub trait Handler {
         for fork_name in ForkName::list_all() {
             if !self.disabled_forks().contains(&fork_name) && self.is_enabled_for_fork(fork_name) {
                 self.run_for_fork(fork_name);
+            }
+        }
 
-                if fork_name == EIP7594_FORK
-                    && EIP7594_TESTS.contains(&Self::runner_name())
-                    && self.is_enabled_for_feature(FeatureName::Eip7594)
-                {
-                    self.run_for_feature(EIP7594_FORK, FeatureName::Eip7594);
-                }
+        // Run feature tests for future forks that are not yet added to `ForkName`.
+        // This runs tests in the directory named by the feature instead of the fork name.
+        // e.g. consensus-spec-tests/tests/general/[feature_name]/[runner_name]
+        // e.g. consensus-spec-tests/tests/general/peerdas/ssz_static
+        for feature_name in FeatureName::list_all() {
+            if self.is_enabled_for_feature(feature_name) {
+                self.run_for_feature(feature_name);
             }
         }
     }
@@ -96,8 +96,9 @@ pub trait Handler {
         crate::results::assert_tests_pass(&name, &handler_path, &results);
     }
 
-    fn run_for_feature(&self, fork_name: ForkName, feature_name: FeatureName) {
+    fn run_for_feature(&self, feature_name: FeatureName) {
         let feature_name_str = feature_name.to_string();
+        let fork_name = feature_name.fork_name();
 
         let handler_path = PathBuf::from(env!("CARGO_MANIFEST_DIR"))
             .join("consensus-spec-tests")
@@ -287,6 +288,10 @@ impl<T, E> SszStaticHandler<T, E> {
         Self::for_forks(vec![ForkName::Electra])
     }
 
+    pub fn fulu_only() -> Self {
+        Self::for_forks(vec![ForkName::Fulu])
+    }
+
     pub fn altair_and_later() -> Self {
         Self::for_forks(ForkName::list_all()[1..].to_vec())
     }
@@ -307,6 +312,10 @@ impl<T, E> SszStaticHandler<T, E> {
         Self::for_forks(ForkName::list_all()[5..].to_vec())
     }
 
+    pub fn fulu_and_later() -> Self {
+        Self::for_forks(ForkName::list_all()[6..].to_vec())
+    }
+
     pub fn pre_electra() -> Self {
         Self::for_forks(ForkName::list_all()[0..5].to_vec())
     }
@@ -344,6 +353,25 @@ where
     fn is_enabled_for_fork(&self, fork_name: ForkName) -> bool {
         self.supported_forks.contains(&fork_name)
     }
+
+    fn is_enabled_for_feature(&self, feature_name: FeatureName) -> bool {
+        // TODO(fulu): to be removed once Fulu types start differing from Electra. We currently run Fulu tests as a
+        // "feature" - this means we use Electra types for Fulu SSZ tests (except for PeerDAS types, e.g. `DataColumnSidecar`).
+        //
+        // This ensures we only run the tests **once** for `Fulu`, using the types matching the
+        // correct fork, e.g. `Fulu` uses SSZ types from `Electra` as of spec test version
+        // `v1.5.0-beta.0`, therefore the `Fulu` tests should get included when testing Deneb types.
+        //
+        // e.g. Fulu test vectors are executed in the 2nd line below, but excluded in the 1st
+        // line when testing the type `AttestationElectra`:
+        //
+        // ```
+        // SszStaticHandler::<AttestationBase<MainnetEthSpec>, MainnetEthSpec>::pre_electra().run();
+        // SszStaticHandler::<AttestationElectra<MainnetEthSpec>, MainnetEthSpec>::electra_only().run();
+        // ```
+        feature_name == FeatureName::Fulu
+            && self.supported_forks.contains(&feature_name.fork_name())
+    }
 }
 
 impl<E> Handler for SszStaticTHCHandler<BeaconState<E>, E>
@@ -363,6 +391,10 @@ where
     fn handler_name(&self) -> String {
         BeaconState::<E>::name().into()
     }
+
+    fn is_enabled_for_feature(&self, feature_name: FeatureName) -> bool {
+        feature_name == FeatureName::Fulu
+    }
 }
 
 impl<T, E> Handler for SszStaticWithSpecHandler<T, E>
@@ -384,6 +416,10 @@ where
     fn handler_name(&self) -> String {
         T::name().into()
     }
+
+    fn is_enabled_for_feature(&self, feature_name: FeatureName) -> bool {
+        feature_name == FeatureName::Fulu
+    }
 }
 
 #[derive(Derivative)]
@@ -841,10 +877,10 @@ impl<E: EthSpec> Handler for KZGVerifyKZGProofHandler<E> {
 
 #[derive(Derivative)]
 #[derivative(Default(bound = ""))]
-pub struct GetCustodyColumnsHandler<E>(PhantomData<E>);
+pub struct GetCustodyGroupsHandler<E>(PhantomData<E>);
 
-impl<E: EthSpec + TypeName> Handler for GetCustodyColumnsHandler<E> {
-    type Case = cases::GetCustodyColumns<E>;
+impl<E: EthSpec + TypeName> Handler for GetCustodyGroupsHandler<E> {
+    type Case = cases::GetCustodyGroups<E>;
 
     fn config_name() -> &'static str {
         E::name()
@@ -855,7 +891,35 @@ impl<E: EthSpec + TypeName> Handler for GetCustodyColumnsHandler<E> {
     }
 
     fn handler_name(&self) -> String {
-        "get_custody_columns".into()
+        "get_custody_groups".into()
+    }
+
+    fn is_enabled_for_feature(&self, feature_name: FeatureName) -> bool {
+        feature_name == FeatureName::Fulu
+    }
+}
+
+#[derive(Derivative)]
+#[derivative(Default(bound = ""))]
+pub struct ComputeColumnsForCustodyGroupHandler<E>(PhantomData<E>);
+
+impl<E: EthSpec + TypeName> Handler for ComputeColumnsForCustodyGroupHandler<E> {
+    type Case = cases::ComputeColumnsForCustodyGroups<E>;
+
+    fn config_name() -> &'static str {
+        E::name()
+    }
+
+    fn runner_name() -> &'static str {
+        "networking"
+    }
+
+    fn handler_name(&self) -> String {
+        "compute_columns_for_custody_group".into()
+    }
+
+    fn is_enabled_for_feature(&self, feature_name: FeatureName) -> bool {
+        feature_name == FeatureName::Fulu
     }
 }
 
@@ -877,6 +941,10 @@ impl<E: EthSpec> Handler for KZGComputeCellsAndKZGProofHandler<E> {
     fn handler_name(&self) -> String {
         "compute_cells_and_kzg_proofs".into()
     }
+
+    fn is_enabled_for_feature(&self, feature_name: FeatureName) -> bool {
+        feature_name == FeatureName::Fulu
+    }
 }
 
 #[derive(Derivative)]
@@ -897,6 +965,10 @@ impl<E: EthSpec> Handler for KZGVerifyCellKZGProofBatchHandler<E> {
     fn handler_name(&self) -> String {
         "verify_cell_kzg_proof_batch".into()
     }
+
+    fn is_enabled_for_feature(&self, feature_name: FeatureName) -> bool {
+        feature_name == FeatureName::Fulu
+    }
 }
 
 #[derive(Derivative)]
@@ -917,6 +989,10 @@ impl<E: EthSpec> Handler for KZGRecoverCellsAndKZGProofHandler<E> {
     fn handler_name(&self) -> String {
         "recover_cells_and_kzg_proofs".into()
     }
+
+    fn is_enabled_for_feature(&self, feature_name: FeatureName) -> bool {
+        feature_name == FeatureName::Fulu
+    }
 }
 
 #[derive(Derivative)]
@@ -963,9 +1039,12 @@ impl<E: EthSpec + TypeName> Handler for KzgInclusionMerkleProofValidityHandler<E
     }
 
     fn is_enabled_for_fork(&self, fork_name: ForkName) -> bool {
-        // Enabled in Deneb
         fork_name.deneb_enabled()
     }
+
+    fn is_enabled_for_feature(&self, feature_name: FeatureName) -> bool {
+        feature_name == FeatureName::Fulu
+    }
 }
 
 #[derive(Derivative)]
diff --git a/testing/ef_tests/src/type_name.rs b/testing/ef_tests/src/type_name.rs
index c50032a63d..285ac951a6 100644
--- a/testing/ef_tests/src/type_name.rs
+++ b/testing/ef_tests/src/type_name.rs
@@ -54,6 +54,7 @@ type_name_generic!(BeaconBlockBodyBellatrix, "BeaconBlockBody");
 type_name_generic!(BeaconBlockBodyCapella, "BeaconBlockBody");
 type_name_generic!(BeaconBlockBodyDeneb, "BeaconBlockBody");
 type_name_generic!(BeaconBlockBodyElectra, "BeaconBlockBody");
+type_name_generic!(BeaconBlockBodyFulu, "BeaconBlockBody");
 type_name!(BeaconBlockHeader);
 type_name_generic!(BeaconState);
 type_name!(BlobIdentifier);
@@ -74,12 +75,14 @@ type_name_generic!(ExecutionPayloadBellatrix, "ExecutionPayload");
 type_name_generic!(ExecutionPayloadCapella, "ExecutionPayload");
 type_name_generic!(ExecutionPayloadDeneb, "ExecutionPayload");
 type_name_generic!(ExecutionPayloadElectra, "ExecutionPayload");
+type_name_generic!(ExecutionPayloadFulu, "ExecutionPayload");
 type_name_generic!(FullPayload, "ExecutionPayload");
 type_name_generic!(ExecutionPayloadHeader);
 type_name_generic!(ExecutionPayloadHeaderBellatrix, "ExecutionPayloadHeader");
 type_name_generic!(ExecutionPayloadHeaderCapella, "ExecutionPayloadHeader");
 type_name_generic!(ExecutionPayloadHeaderDeneb, "ExecutionPayloadHeader");
 type_name_generic!(ExecutionPayloadHeaderElectra, "ExecutionPayloadHeader");
+type_name_generic!(ExecutionPayloadHeaderFulu, "ExecutionPayloadHeader");
 type_name_generic!(ExecutionRequests);
 type_name_generic!(BlindedPayload, "ExecutionPayloadHeader");
 type_name!(Fork);
@@ -93,6 +96,7 @@ type_name_generic!(LightClientBootstrapAltair, "LightClientBootstrap");
 type_name_generic!(LightClientBootstrapCapella, "LightClientBootstrap");
 type_name_generic!(LightClientBootstrapDeneb, "LightClientBootstrap");
 type_name_generic!(LightClientBootstrapElectra, "LightClientBootstrap");
+type_name_generic!(LightClientBootstrapFulu, "LightClientBootstrap");
 type_name_generic!(LightClientFinalityUpdate);
 type_name_generic!(LightClientFinalityUpdateAltair, "LightClientFinalityUpdate");
 type_name_generic!(
@@ -104,11 +108,13 @@ type_name_generic!(
     LightClientFinalityUpdateElectra,
     "LightClientFinalityUpdate"
 );
+type_name_generic!(LightClientFinalityUpdateFulu, "LightClientFinalityUpdate");
 type_name_generic!(LightClientHeader);
 type_name_generic!(LightClientHeaderAltair, "LightClientHeader");
 type_name_generic!(LightClientHeaderCapella, "LightClientHeader");
 type_name_generic!(LightClientHeaderDeneb, "LightClientHeader");
 type_name_generic!(LightClientHeaderElectra, "LightClientHeader");
+type_name_generic!(LightClientHeaderFulu, "LightClientHeader");
 type_name_generic!(LightClientOptimisticUpdate);
 type_name_generic!(
     LightClientOptimisticUpdateAltair,
@@ -126,11 +132,16 @@ type_name_generic!(
     LightClientOptimisticUpdateElectra,
     "LightClientOptimisticUpdate"
 );
+type_name_generic!(
+    LightClientOptimisticUpdateFulu,
+    "LightClientOptimisticUpdate"
+);
 type_name_generic!(LightClientUpdate);
 type_name_generic!(LightClientUpdateAltair, "LightClientUpdate");
 type_name_generic!(LightClientUpdateCapella, "LightClientUpdate");
 type_name_generic!(LightClientUpdateDeneb, "LightClientUpdate");
 type_name_generic!(LightClientUpdateElectra, "LightClientUpdate");
+type_name_generic!(LightClientUpdateFulu, "LightClientUpdate");
 type_name_generic!(PendingAttestation);
 type_name!(PendingConsolidation);
 type_name!(PendingPartialWithdrawal);
diff --git a/testing/ef_tests/tests/tests.rs b/testing/ef_tests/tests/tests.rs
index 292625a371..bba7efde49 100644
--- a/testing/ef_tests/tests/tests.rs
+++ b/testing/ef_tests/tests/tests.rs
@@ -276,9 +276,9 @@ mod ssz_static {
     fn attestation() {
         SszStaticHandler::<AttestationBase<MinimalEthSpec>, MinimalEthSpec>::pre_electra().run();
         SszStaticHandler::<AttestationBase<MainnetEthSpec>, MainnetEthSpec>::pre_electra().run();
-        SszStaticHandler::<AttestationElectra<MinimalEthSpec>, MinimalEthSpec>::electra_only()
+        SszStaticHandler::<AttestationElectra<MinimalEthSpec>, MinimalEthSpec>::electra_and_later()
             .run();
-        SszStaticHandler::<AttestationElectra<MainnetEthSpec>, MainnetEthSpec>::electra_only()
+        SszStaticHandler::<AttestationElectra<MainnetEthSpec>, MainnetEthSpec>::electra_and_later()
             .run();
     }
 
@@ -288,9 +288,9 @@ mod ssz_static {
             .run();
         SszStaticHandler::<AttesterSlashingBase<MainnetEthSpec>, MainnetEthSpec>::pre_electra()
             .run();
-        SszStaticHandler::<AttesterSlashingElectra<MinimalEthSpec>, MinimalEthSpec>::electra_only()
+        SszStaticHandler::<AttesterSlashingElectra<MinimalEthSpec>, MinimalEthSpec>::electra_and_later()
             .run();
-        SszStaticHandler::<AttesterSlashingElectra<MainnetEthSpec>, MainnetEthSpec>::electra_only()
+        SszStaticHandler::<AttesterSlashingElectra<MainnetEthSpec>, MainnetEthSpec>::electra_and_later()
             .run();
     }
 
@@ -300,9 +300,9 @@ mod ssz_static {
             .run();
         SszStaticHandler::<IndexedAttestationBase<MainnetEthSpec>, MainnetEthSpec>::pre_electra()
             .run();
-        SszStaticHandler::<IndexedAttestationElectra<MinimalEthSpec>, MinimalEthSpec>::electra_only()
+        SszStaticHandler::<IndexedAttestationElectra<MinimalEthSpec>, MinimalEthSpec>::electra_and_later()
             .run();
-        SszStaticHandler::<IndexedAttestationElectra<MainnetEthSpec>, MainnetEthSpec>::electra_only()
+        SszStaticHandler::<IndexedAttestationElectra<MainnetEthSpec>, MainnetEthSpec>::electra_and_later()
             .run();
     }
 
@@ -314,10 +314,10 @@ mod ssz_static {
         SszStaticHandler::<SignedAggregateAndProofBase<MainnetEthSpec>, MainnetEthSpec>::pre_electra(
         )
         .run();
-        SszStaticHandler::<SignedAggregateAndProofElectra<MinimalEthSpec>, MinimalEthSpec>::electra_only(
+        SszStaticHandler::<SignedAggregateAndProofElectra<MinimalEthSpec>, MinimalEthSpec>::electra_and_later(
         )
         .run();
-        SszStaticHandler::<SignedAggregateAndProofElectra<MainnetEthSpec>, MainnetEthSpec>::electra_only(
+        SszStaticHandler::<SignedAggregateAndProofElectra<MainnetEthSpec>, MainnetEthSpec>::electra_and_later(
         )
         .run();
     }
@@ -328,10 +328,10 @@ mod ssz_static {
             .run();
         SszStaticHandler::<AggregateAndProofBase<MainnetEthSpec>, MainnetEthSpec>::pre_electra()
             .run();
-        SszStaticHandler::<AggregateAndProofElectra<MinimalEthSpec>, MinimalEthSpec>::electra_only(
+        SszStaticHandler::<AggregateAndProofElectra<MinimalEthSpec>, MinimalEthSpec>::electra_and_later(
         )
         .run();
-        SszStaticHandler::<AggregateAndProofElectra<MainnetEthSpec>, MainnetEthSpec>::electra_only(
+        SszStaticHandler::<AggregateAndProofElectra<MainnetEthSpec>, MainnetEthSpec>::electra_and_later(
         )
         .run();
     }
@@ -361,6 +361,8 @@ mod ssz_static {
             .run();
         SszStaticHandler::<BeaconBlockBodyElectra<MainnetEthSpec>, MainnetEthSpec>::electra_only()
             .run();
+        SszStaticHandler::<BeaconBlockBodyFulu<MinimalEthSpec>, MinimalEthSpec>::fulu_only().run();
+        SszStaticHandler::<BeaconBlockBodyFulu<MainnetEthSpec>, MainnetEthSpec>::fulu_only().run();
     }
 
     // Altair and later
@@ -399,6 +401,10 @@ mod ssz_static {
             .run();
         SszStaticHandler::<LightClientBootstrapElectra<MainnetEthSpec>, MainnetEthSpec>::electra_only()
             .run();
+        SszStaticHandler::<LightClientBootstrapFulu<MinimalEthSpec>, MinimalEthSpec>::fulu_only()
+            .run();
+        SszStaticHandler::<LightClientBootstrapFulu<MainnetEthSpec>, MainnetEthSpec>::fulu_only()
+            .run();
     }
 
     // LightClientHeader has no internal indicator of which fork it is for, so we test it separately.
@@ -430,6 +436,10 @@ mod ssz_static {
         SszStaticHandler::<LightClientHeaderElectra<MainnetEthSpec>, MainnetEthSpec>::electra_only(
         )
         .run();
+        SszStaticHandler::<LightClientHeaderFulu<MinimalEthSpec>, MinimalEthSpec>::fulu_only()
+            .run();
+        SszStaticHandler::<LightClientHeaderFulu<MainnetEthSpec>, MainnetEthSpec>::fulu_only()
+            .run();
     }
 
     // LightClientOptimisticUpdate has no internal indicator of which fork it is for, so we test it separately.
@@ -445,6 +455,8 @@ mod ssz_static {
         SszStaticHandler::<LightClientOptimisticUpdateDeneb<MainnetEthSpec>, MainnetEthSpec>::deneb_only().run();
         SszStaticHandler::<LightClientOptimisticUpdateElectra<MinimalEthSpec>, MinimalEthSpec>::electra_only().run();
         SszStaticHandler::<LightClientOptimisticUpdateElectra<MainnetEthSpec>, MainnetEthSpec>::electra_only().run();
+        SszStaticHandler::<LightClientOptimisticUpdateFulu<MinimalEthSpec>, MinimalEthSpec>::fulu_only().run();
+        SszStaticHandler::<LightClientOptimisticUpdateFulu<MainnetEthSpec>, MainnetEthSpec>::fulu_only().run();
     }
 
     // LightClientFinalityUpdate has no internal indicator of which fork it is for, so we test it separately.
@@ -480,6 +492,12 @@ mod ssz_static {
         SszStaticHandler::<LightClientFinalityUpdateElectra<MainnetEthSpec>, MainnetEthSpec>::electra_only(
         )
             .run();
+        SszStaticHandler::<LightClientFinalityUpdateFulu<MinimalEthSpec>, MinimalEthSpec>::fulu_only(
+        )
+            .run();
+        SszStaticHandler::<LightClientFinalityUpdateFulu<MainnetEthSpec>, MainnetEthSpec>::fulu_only(
+        )
+            .run();
     }
 
     // LightClientUpdate has no internal indicator of which fork it is for, so we test it separately.
@@ -509,6 +527,10 @@ mod ssz_static {
         SszStaticHandler::<LightClientUpdateElectra<MainnetEthSpec>, MainnetEthSpec>::electra_only(
         )
         .run();
+        SszStaticHandler::<LightClientUpdateFulu<MinimalEthSpec>, MinimalEthSpec>::fulu_only()
+            .run();
+        SszStaticHandler::<LightClientUpdateFulu<MainnetEthSpec>, MainnetEthSpec>::fulu_only()
+            .run();
     }
 
     #[test]
@@ -566,6 +588,8 @@ mod ssz_static {
             .run();
         SszStaticHandler::<ExecutionPayloadElectra<MainnetEthSpec>, MainnetEthSpec>::electra_only()
             .run();
+        SszStaticHandler::<ExecutionPayloadFulu<MinimalEthSpec>, MinimalEthSpec>::fulu_only().run();
+        SszStaticHandler::<ExecutionPayloadFulu<MainnetEthSpec>, MainnetEthSpec>::fulu_only().run();
     }
 
     #[test]
@@ -586,6 +610,10 @@ mod ssz_static {
             ::electra_only().run();
         SszStaticHandler::<ExecutionPayloadHeaderElectra<MainnetEthSpec>, MainnetEthSpec>
             ::electra_only().run();
+        SszStaticHandler::<ExecutionPayloadHeaderFulu<MinimalEthSpec>, MinimalEthSpec>::fulu_only()
+            .run();
+        SszStaticHandler::<ExecutionPayloadHeaderFulu<MainnetEthSpec>, MainnetEthSpec>::fulu_only()
+            .run();
     }
 
     #[test]
@@ -626,18 +654,18 @@ mod ssz_static {
 
     #[test]
     fn data_column_sidecar() {
-        SszStaticHandler::<DataColumnSidecar<MinimalEthSpec>, MinimalEthSpec>::deneb_only()
-            .run_for_feature(ForkName::Deneb, FeatureName::Eip7594);
-        SszStaticHandler::<DataColumnSidecar<MainnetEthSpec>, MainnetEthSpec>::deneb_only()
-            .run_for_feature(ForkName::Deneb, FeatureName::Eip7594);
+        SszStaticHandler::<DataColumnSidecar<MinimalEthSpec>, MinimalEthSpec>::default()
+            .run_for_feature(FeatureName::Fulu);
+        SszStaticHandler::<DataColumnSidecar<MainnetEthSpec>, MainnetEthSpec>::default()
+            .run_for_feature(FeatureName::Fulu);
     }
 
     #[test]
     fn data_column_identifier() {
-        SszStaticHandler::<DataColumnIdentifier, MinimalEthSpec>::deneb_only()
-            .run_for_feature(ForkName::Deneb, FeatureName::Eip7594);
-        SszStaticHandler::<DataColumnIdentifier, MainnetEthSpec>::deneb_only()
-            .run_for_feature(ForkName::Deneb, FeatureName::Eip7594);
+        SszStaticHandler::<DataColumnIdentifier, MinimalEthSpec>::default()
+            .run_for_feature(FeatureName::Fulu);
+        SszStaticHandler::<DataColumnIdentifier, MainnetEthSpec>::default()
+            .run_for_feature(FeatureName::Fulu);
     }
 
     #[test]
@@ -901,20 +929,17 @@ fn kzg_verify_kzg_proof() {
 
 #[test]
 fn kzg_compute_cells_and_proofs() {
-    KZGComputeCellsAndKZGProofHandler::<MainnetEthSpec>::default()
-        .run_for_feature(ForkName::Deneb, FeatureName::Eip7594);
+    KZGComputeCellsAndKZGProofHandler::<MainnetEthSpec>::default().run();
 }
 
 #[test]
 fn kzg_verify_cell_proof_batch() {
-    KZGVerifyCellKZGProofBatchHandler::<MainnetEthSpec>::default()
-        .run_for_feature(ForkName::Deneb, FeatureName::Eip7594);
+    KZGVerifyCellKZGProofBatchHandler::<MainnetEthSpec>::default().run();
 }
 
 #[test]
 fn kzg_recover_cells_and_proofs() {
-    KZGRecoverCellsAndKZGProofHandler::<MainnetEthSpec>::default()
-        .run_for_feature(ForkName::Deneb, FeatureName::Eip7594);
+    KZGRecoverCellsAndKZGProofHandler::<MainnetEthSpec>::default().run();
 }
 
 #[test]
@@ -948,9 +973,13 @@ fn rewards() {
 }
 
 #[test]
-fn get_custody_columns() {
-    GetCustodyColumnsHandler::<MainnetEthSpec>::default()
-        .run_for_feature(ForkName::Deneb, FeatureName::Eip7594);
-    GetCustodyColumnsHandler::<MinimalEthSpec>::default()
-        .run_for_feature(ForkName::Deneb, FeatureName::Eip7594);
+fn get_custody_groups() {
+    GetCustodyGroupsHandler::<MainnetEthSpec>::default().run();
+    GetCustodyGroupsHandler::<MinimalEthSpec>::default().run()
+}
+
+#[test]
+fn compute_columns_for_custody_group() {
+    ComputeColumnsForCustodyGroupHandler::<MainnetEthSpec>::default().run();
+    ComputeColumnsForCustodyGroupHandler::<MinimalEthSpec>::default().run();
 }
diff --git a/testing/node_test_rig/src/lib.rs b/testing/node_test_rig/src/lib.rs
index ac01c84b9d..6e632ccf54 100644
--- a/testing/node_test_rig/src/lib.rs
+++ b/testing/node_test_rig/src/lib.rs
@@ -7,6 +7,7 @@ use environment::RuntimeContext;
 use eth2::{reqwest::ClientBuilder, BeaconNodeHttpClient, Timeouts};
 use sensitive_url::SensitiveUrl;
 use std::path::PathBuf;
+use std::sync::Arc;
 use std::time::Duration;
 use std::time::{SystemTime, UNIX_EPOCH};
 use tempfile::{Builder as TempBuilder, TempDir};
@@ -248,8 +249,14 @@ impl<E: EthSpec> LocalExecutionNode<E> {
         if let Err(e) = std::fs::write(jwt_file_path, config.jwt_key.hex_string()) {
             panic!("Failed to write jwt file {}", e);
         }
+        let spec = Arc::new(E::default_spec());
         Self {
-            server: MockServer::new_with_config(&context.executor.handle().unwrap(), config, None),
+            server: MockServer::new_with_config(
+                &context.executor.handle().unwrap(),
+                config,
+                spec,
+                None,
+            ),
             datadir,
         }
     }
diff --git a/testing/simulator/src/basic_sim.rs b/testing/simulator/src/basic_sim.rs
index 8f659a893f..82a7028582 100644
--- a/testing/simulator/src/basic_sim.rs
+++ b/testing/simulator/src/basic_sim.rs
@@ -22,7 +22,8 @@ const ALTAIR_FORK_EPOCH: u64 = 0;
 const BELLATRIX_FORK_EPOCH: u64 = 0;
 const CAPELLA_FORK_EPOCH: u64 = 1;
 const DENEB_FORK_EPOCH: u64 = 2;
-//const ELECTRA_FORK_EPOCH: u64 = 3;
+// const ELECTRA_FORK_EPOCH: u64 = 3;
+// const FULU_FORK_EPOCH: u64  = 4;
 
 const SUGGESTED_FEE_RECIPIENT: [u8; 20] =
     [0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1];
@@ -118,6 +119,7 @@ pub fn run_basic_sim(matches: &ArgMatches) -> Result<(), String> {
     spec.capella_fork_epoch = Some(Epoch::new(CAPELLA_FORK_EPOCH));
     spec.deneb_fork_epoch = Some(Epoch::new(DENEB_FORK_EPOCH));
     //spec.electra_fork_epoch = Some(Epoch::new(ELECTRA_FORK_EPOCH));
+    //spec.fulu_fork_epoch = Some(Epoch::new(FULU_FORK_EPOCH));
     let spec = Arc::new(spec);
     env.eth2_config.spec = spec.clone();
 
diff --git a/testing/simulator/src/fallback_sim.rs b/testing/simulator/src/fallback_sim.rs
index b3b9a46001..7d4bdfa264 100644
--- a/testing/simulator/src/fallback_sim.rs
+++ b/testing/simulator/src/fallback_sim.rs
@@ -21,7 +21,8 @@ const ALTAIR_FORK_EPOCH: u64 = 0;
 const BELLATRIX_FORK_EPOCH: u64 = 0;
 const CAPELLA_FORK_EPOCH: u64 = 1;
 const DENEB_FORK_EPOCH: u64 = 2;
-//const ELECTRA_FORK_EPOCH: u64 = 3;
+// const ELECTRA_FORK_EPOCH: u64 = 3;
+// const FULU_FORK_EPOCH: u64 = 4;
 
 // Since simulator tests are non-deterministic and there is a non-zero chance of missed
 // attestations, define an acceptable network-wide attestation performance.
@@ -123,6 +124,7 @@ pub fn run_fallback_sim(matches: &ArgMatches) -> Result<(), String> {
     spec.capella_fork_epoch = Some(Epoch::new(CAPELLA_FORK_EPOCH));
     spec.deneb_fork_epoch = Some(Epoch::new(DENEB_FORK_EPOCH));
     //spec.electra_fork_epoch = Some(Epoch::new(ELECTRA_FORK_EPOCH));
+    //spec.fulu_fork_epoch = Some(Epoch::new(FULU_FORK_EPOCH));
     let spec = Arc::new(spec);
     env.eth2_config.spec = spec.clone();
 
diff --git a/testing/simulator/src/local_network.rs b/testing/simulator/src/local_network.rs
index 59efc09baa..a95c15c231 100644
--- a/testing/simulator/src/local_network.rs
+++ b/testing/simulator/src/local_network.rs
@@ -88,6 +88,11 @@ fn default_mock_execution_config<E: EthSpec>(
                 + spec.seconds_per_slot * E::slots_per_epoch() * electra_fork_epoch.as_u64(),
         )
     }
+    if let Some(fulu_fork_epoch) = spec.fulu_fork_epoch {
+        mock_execution_config.osaka_time = Some(
+            genesis_time + spec.seconds_per_slot * E::slots_per_epoch() * fulu_fork_epoch.as_u64(),
+        )
+    }
 
     mock_execution_config
 }
diff --git a/validator_client/beacon_node_fallback/src/lib.rs b/validator_client/beacon_node_fallback/src/lib.rs
index daa0802f9b..526479d67f 100644
--- a/validator_client/beacon_node_fallback/src/lib.rs
+++ b/validator_client/beacon_node_fallback/src/lib.rs
@@ -361,6 +361,14 @@ impl<E: EthSpec> CandidateBeaconNode<E> {
                 "endpoint_electra_fork_epoch" => ?beacon_node_spec.electra_fork_epoch,
                 "hint" => UPDATE_REQUIRED_LOG_HINT,
             );
+        } else if beacon_node_spec.fulu_fork_epoch != spec.fulu_fork_epoch {
+            warn!(
+            log,
+                    "Beacon node has mismatched Fulu fork epoch";
+                    "endpoint" => %self.beacon_node,
+                    "endpoint_fulu_fork_epoch" => ?beacon_node_spec.fulu_fork_epoch,
+                    "hint" => UPDATE_REQUIRED_LOG_HINT,
+                );
         }
 
         Ok(())
diff --git a/validator_client/doppelganger_service/src/lib.rs b/validator_client/doppelganger_service/src/lib.rs
index 35228fe354..4a593c2700 100644
--- a/validator_client/doppelganger_service/src/lib.rs
+++ b/validator_client/doppelganger_service/src/lib.rs
@@ -162,7 +162,7 @@ impl DoppelgangerState {
 /// If the BN fails to respond to either of these requests, simply return an empty response.
 /// This behaviour is to help prevent spurious failures on the BN from needlessly preventing
 /// doppelganger progression.
-async fn beacon_node_liveness<'a, T: 'static + SlotClock, E: EthSpec>(
+async fn beacon_node_liveness<T: 'static + SlotClock, E: EthSpec>(
     beacon_nodes: Arc<BeaconNodeFallback<T, E>>,
     log: Logger,
     current_epoch: Epoch,
diff --git a/validator_client/http_api/Cargo.toml b/validator_client/http_api/Cargo.toml
index 76a021ab8c..651e658a7a 100644
--- a/validator_client/http_api/Cargo.toml
+++ b/validator_client/http_api/Cargo.toml
@@ -21,6 +21,7 @@ eth2_keystore  = { workspace = true }
 ethereum_serde_utils = { workspace = true }
 filesystem = { workspace = true }
 graffiti_file = { workspace = true }
+health_metrics = { workspace = true }
 initialized_validators = { workspace = true }
 lighthouse_version = { workspace = true }
 logging = { workspace = true }
diff --git a/validator_client/http_api/src/lib.rs b/validator_client/http_api/src/lib.rs
index f3dab3780c..9c3e3da63d 100644
--- a/validator_client/http_api/src/lib.rs
+++ b/validator_client/http_api/src/lib.rs
@@ -32,6 +32,7 @@ use eth2::lighthouse_vc::{
         PublicKeyBytes, SetGraffitiRequest,
     },
 };
+use health_metrics::observe::Observe;
 use lighthouse_version::version_with_platform;
 use logging::SSELoggingComponents;
 use parking_lot::RwLock;
@@ -106,6 +107,7 @@ pub struct Config {
 
 impl Default for Config {
     fn default() -> Self {
+        // This value is always overridden when building config from CLI.
         let http_token_path = dirs::home_dir()
             .unwrap_or_else(|| PathBuf::from("."))
             .join(DEFAULT_ROOT_DIR)
diff --git a/validator_client/http_api/src/test_utils.rs b/validator_client/http_api/src/test_utils.rs
index 390095eec7..0531626846 100644
--- a/validator_client/http_api/src/test_utils.rs
+++ b/validator_client/http_api/src/test_utils.rs
@@ -251,9 +251,9 @@ impl ApiTester {
     pub async fn test_get_lighthouse_spec(self) -> Self {
         let result = self
             .client
-            .get_lighthouse_spec::<ConfigAndPresetElectra>()
+            .get_lighthouse_spec::<ConfigAndPresetFulu>()
             .await
-            .map(|res| ConfigAndPreset::Electra(res.data))
+            .map(|res| ConfigAndPreset::Fulu(res.data))
             .unwrap();
         let expected = ConfigAndPreset::from_chain_spec::<E>(&E::default_spec(), None);
 
diff --git a/validator_client/http_api/src/tests.rs b/validator_client/http_api/src/tests.rs
index 7ea3d7ebaa..4e9acc4237 100644
--- a/validator_client/http_api/src/tests.rs
+++ b/validator_client/http_api/src/tests.rs
@@ -214,9 +214,9 @@ impl ApiTester {
     pub async fn test_get_lighthouse_spec(self) -> Self {
         let result = self
             .client
-            .get_lighthouse_spec::<ConfigAndPresetElectra>()
+            .get_lighthouse_spec::<ConfigAndPresetFulu>()
             .await
-            .map(|res| ConfigAndPreset::Electra(res.data))
+            .map(|res| ConfigAndPreset::Fulu(res.data))
             .unwrap();
         let expected = ConfigAndPreset::from_chain_spec::<E>(&E::default_spec(), None);
 
diff --git a/validator_client/http_metrics/Cargo.toml b/validator_client/http_metrics/Cargo.toml
index c29a4d18fa..a3432410bc 100644
--- a/validator_client/http_metrics/Cargo.toml
+++ b/validator_client/http_metrics/Cargo.toml
@@ -5,6 +5,7 @@ edition = { workspace = true }
 authors = ["Sigma Prime <contact@sigmaprime.io>"]
 
 [dependencies]
+health_metrics = { workspace = true }
 lighthouse_version = { workspace = true }
 malloc_utils = { workspace = true }
 metrics = { workspace = true }
diff --git a/validator_client/http_metrics/src/lib.rs b/validator_client/http_metrics/src/lib.rs
index 984b752e5a..f1c6d4ed8a 100644
--- a/validator_client/http_metrics/src/lib.rs
+++ b/validator_client/http_metrics/src/lib.rs
@@ -206,7 +206,7 @@ pub fn gather_prometheus_metrics<E: EthSpec>(
         scrape_allocator_metrics();
     }
 
-    warp_utils::metrics::scrape_health_metrics();
+    health_metrics::metrics::scrape_health_metrics();
 
     encoder
         .encode(&metrics::gather(), &mut buffer)
diff --git a/validator_client/signing_method/src/web3signer.rs b/validator_client/signing_method/src/web3signer.rs
index a04922c8c0..885b53683f 100644
--- a/validator_client/signing_method/src/web3signer.rs
+++ b/validator_client/signing_method/src/web3signer.rs
@@ -30,6 +30,7 @@ pub enum ForkName {
     Capella,
     Deneb,
     Electra,
+    Fulu,
 }
 
 #[derive(Debug, PartialEq, Serialize)]
@@ -109,6 +110,11 @@ impl<'a, E: EthSpec, Payload: AbstractExecPayload<E>> Web3SignerObject<'a, E, Pa
                 block: None,
                 block_header: Some(block.block_header()),
             }),
+            BeaconBlock::Fulu(_) => Ok(Web3SignerObject::BeaconBlock {
+                version: ForkName::Fulu,
+                block: None,
+                block_header: Some(block.block_header()),
+            }),
         }
     }
 
diff --git a/validator_client/slashing_protection/src/slashing_database.rs b/validator_client/slashing_protection/src/slashing_database.rs
index baaf930c68..71611339f9 100644
--- a/validator_client/slashing_protection/src/slashing_database.rs
+++ b/validator_client/slashing_protection/src/slashing_database.rs
@@ -1113,9 +1113,7 @@ fn max_or<T: Copy + Ord>(opt_x: Option<T>, y: T) -> T {
 ///
 /// If prev is `None` and `new` is `Some` then `true` is returned.
 fn monotonic<T: PartialOrd>(new: Option<T>, prev: Option<T>) -> bool {
-    new.map_or(false, |new_val| {
-        prev.map_or(true, |prev_val| new_val >= prev_val)
-    })
+    new.is_some_and(|new_val| prev.map_or(true, |prev_val| new_val >= prev_val))
 }
 
 /// The result of importing a single entry from an interchange file.
diff --git a/validator_client/src/config.rs b/validator_client/src/config.rs
index 0fecb5202d..bb72ef81c8 100644
--- a/validator_client/src/config.rs
+++ b/validator_client/src/config.rs
@@ -314,10 +314,11 @@ impl Config {
             config.http_api.store_passwords_in_secrets_dir = true;
         }
 
-        if cli_args.get_one::<String>("http-token-path").is_some() {
-            config.http_api.http_token_path = parse_required(cli_args, "http-token-path")
-                // For backward compatibility, default to the path under the validator dir if not provided.
-                .unwrap_or_else(|_| config.validator_dir.join(PK_FILENAME));
+        if let Some(http_token_path) = cli_args.get_one::<String>("http-token-path") {
+            config.http_api.http_token_path = PathBuf::from(http_token_path);
+        } else {
+            // For backward compatibility, default to the path under the validator dir if not provided.
+            config.http_api.http_token_path = config.validator_dir.join(PK_FILENAME);
         }
 
         /*
diff --git a/validator_client/validator_services/Cargo.toml b/validator_client/validator_services/Cargo.toml
index 21f0ae2d77..b4495a7c81 100644
--- a/validator_client/validator_services/Cargo.toml
+++ b/validator_client/validator_services/Cargo.toml
@@ -8,6 +8,7 @@ authors = ["Sigma Prime <contact@sigmaprime.io>"]
 beacon_node_fallback = { workspace = true }
 bls =  { workspace = true }
 doppelganger_service = { workspace = true }
+either = { workspace = true }
 environment = { workspace = true }
 eth2 = { workspace = true }
 futures = { workspace = true }
diff --git a/validator_client/validator_services/src/attestation_service.rs b/validator_client/validator_services/src/attestation_service.rs
index e31ad4f661..9a6f94d52b 100644
--- a/validator_client/validator_services/src/attestation_service.rs
+++ b/validator_client/validator_services/src/attestation_service.rs
@@ -1,5 +1,6 @@
 use crate::duties_service::{DutiesService, DutyAndProof};
 use beacon_node_fallback::{ApiTopic, BeaconNodeFallback};
+use either::Either;
 use environment::RuntimeContext;
 use futures::future::join_all;
 use slog::{crit, debug, error, info, trace, warn};
@@ -457,8 +458,34 @@ impl<T: SlotClock + 'static, E: EthSpec> AttestationService<T, E> {
                     &[validator_metrics::ATTESTATIONS_HTTP_POST],
                 );
                 if fork_name.electra_enabled() {
+                    let single_attestations = attestations
+                        .iter()
+                        .zip(validator_indices)
+                        .filter_map(|(a, i)| {
+                            match a.to_single_attestation_with_attester_index(*i) {
+                                Ok(a) => Some(a),
+                                Err(e) => {
+                                    // This shouldn't happen unless BN and VC are out of sync with
+                                    // respect to the Electra fork.
+                                    error!(
+                                        log,
+                                        "Unable to convert to SingleAttestation";
+                                        "error" => ?e,
+                                        "committee_index" => attestation_data.index,
+                                        "slot" => slot.as_u64(),
+                                        "type" => "unaggregated",
+                                    );
+                                    None
+                                }
+                            }
+                        })
+                        .collect::<Vec<_>>();
+
                     beacon_node
-                        .post_beacon_pool_attestations_v2(attestations, fork_name)
+                        .post_beacon_pool_attestations_v2::<E>(
+                            Either::Right(single_attestations),
+                            fork_name,
+                        )
                         .await
                 } else {
                     beacon_node
diff --git a/validator_client/validator_services/src/preparation_service.rs b/validator_client/validator_services/src/preparation_service.rs
index 480f4af2b3..fe6eab3a8a 100644
--- a/validator_client/validator_services/src/preparation_service.rs
+++ b/validator_client/validator_services/src/preparation_service.rs
@@ -258,7 +258,7 @@ impl<T: SlotClock + 'static, E: EthSpec> PreparationService<T, E> {
             .slot_clock
             .now()
             .map_or(E::genesis_epoch(), |slot| slot.epoch(E::slots_per_epoch()));
-        spec.bellatrix_fork_epoch.map_or(false, |fork_epoch| {
+        spec.bellatrix_fork_epoch.is_some_and(|fork_epoch| {
             current_epoch + PROPOSER_PREPARATION_LOOKAHEAD_EPOCHS >= fork_epoch
         })
     }
diff --git a/validator_client/validator_services/src/sync.rs b/validator_client/validator_services/src/sync.rs
index af501326f4..dd3e05088e 100644
--- a/validator_client/validator_services/src/sync.rs
+++ b/validator_client/validator_services/src/sync.rs
@@ -94,7 +94,7 @@ impl<E: EthSpec> SyncDutiesMap<E> {
         self.committees
             .read()
             .get(&committee_period)
-            .map_or(false, |committee_duties| {
+            .is_some_and(|committee_duties| {
                 let validator_duties = committee_duties.validators.read();
                 validator_indices
                     .iter()
diff --git a/validator_manager/src/create_validators.rs b/validator_manager/src/create_validators.rs
index d4403b4613..b40fe61a82 100644
--- a/validator_manager/src/create_validators.rs
+++ b/validator_manager/src/create_validators.rs
@@ -286,7 +286,7 @@ struct ValidatorsAndDeposits {
 }
 
 impl ValidatorsAndDeposits {
-    async fn new<'a, E: EthSpec>(config: CreateConfig, spec: &ChainSpec) -> Result<Self, String> {
+    async fn new<E: EthSpec>(config: CreateConfig, spec: &ChainSpec) -> Result<Self, String> {
         let CreateConfig {
             // The output path is handled upstream.
             output_path: _,
@@ -545,7 +545,7 @@ pub async fn cli_run<E: EthSpec>(
     }
 }
 
-async fn run<'a, E: EthSpec>(config: CreateConfig, spec: &ChainSpec) -> Result<(), String> {
+async fn run<E: EthSpec>(config: CreateConfig, spec: &ChainSpec) -> Result<(), String> {
     let output_path = config.output_path.clone();
 
     if !output_path.exists() {
diff --git a/validator_manager/src/delete_validators.rs b/validator_manager/src/delete_validators.rs
index a2d6c062fa..5ef647c5af 100644
--- a/validator_manager/src/delete_validators.rs
+++ b/validator_manager/src/delete_validators.rs
@@ -86,7 +86,7 @@ pub async fn cli_run(matches: &ArgMatches, dump_config: DumpConfig) -> Result<()
     }
 }
 
-async fn run<'a>(config: DeleteConfig) -> Result<(), String> {
+async fn run(config: DeleteConfig) -> Result<(), String> {
     let DeleteConfig {
         vc_url,
         vc_token_path,
diff --git a/validator_manager/src/import_validators.rs b/validator_manager/src/import_validators.rs
index 3cebc10bb3..63c7ca4596 100644
--- a/validator_manager/src/import_validators.rs
+++ b/validator_manager/src/import_validators.rs
@@ -209,7 +209,7 @@ pub async fn cli_run(matches: &ArgMatches, dump_config: DumpConfig) -> Result<()
     }
 }
 
-async fn run<'a>(config: ImportConfig) -> Result<(), String> {
+async fn run(config: ImportConfig) -> Result<(), String> {
     let ImportConfig {
         validators_file_path,
         keystore_file_path,
diff --git a/validator_manager/src/list_validators.rs b/validator_manager/src/list_validators.rs
index e3deb0b21a..a0a1c5fb40 100644
--- a/validator_manager/src/list_validators.rs
+++ b/validator_manager/src/list_validators.rs
@@ -58,7 +58,7 @@ pub async fn cli_run(matches: &ArgMatches, dump_config: DumpConfig) -> Result<()
     }
 }
 
-async fn run<'a>(config: ListConfig) -> Result<Vec<SingleKeystoreResponse>, String> {
+async fn run(config: ListConfig) -> Result<Vec<SingleKeystoreResponse>, String> {
     let ListConfig {
         vc_url,
         vc_token_path,
diff --git a/validator_manager/src/move_validators.rs b/validator_manager/src/move_validators.rs
index 4d0820f5a8..abac071673 100644
--- a/validator_manager/src/move_validators.rs
+++ b/validator_manager/src/move_validators.rs
@@ -277,7 +277,7 @@ pub async fn cli_run(matches: &ArgMatches, dump_config: DumpConfig) -> Result<()
     }
 }
 
-async fn run<'a>(config: MoveConfig) -> Result<(), String> {
+async fn run(config: MoveConfig) -> Result<(), String> {
     let MoveConfig {
         src_vc_url,
         src_vc_token_path,
diff --git a/wordlist.txt b/wordlist.txt
index 6287366cbc..bb8b46b525 100644
--- a/wordlist.txt
+++ b/wordlist.txt
@@ -162,6 +162,7 @@ keypair
 keypairs
 keystore
 keystores
+leveldb
 linter
 linux
 localhost
@@ -191,6 +192,7 @@ pre
 pubkey
 pubkeys
 rc
+redb
 reimport
 resync
 roadmap