diff --git a/protos/build.rs b/protos/build.rs
index d8becfa519..108d9e2ddb 100644
--- a/protos/build.rs
+++ b/protos/build.rs
@@ -1,8 +1,10 @@
 extern crate protoc_grpcio;
 
+use std::path::Path;
+
 fn main() {
-    let proto_root = "src/";
-    println!("cargo:rerun-if-changed={}", proto_root);
+    let proto_root = Path::new("src");
+    println!("cargo:rerun-if-changed={}", proto_root.display());
     protoc_grpcio::compile_grpc_protos(&["services.proto"], &[proto_root], &proto_root)
         .expect("Failed to compile gRPC definitions!");
 }