diff --git a/pkgs/by-name/or/or-tools/pybind11-protobuf.nix b/pkgs/by-name/or/or-tools/pybind11-protobuf.nix
index 32947bbc038f..6e4df8b78a37 100644
--- a/pkgs/by-name/or/or-tools/pybind11-protobuf.nix
+++ b/pkgs/by-name/or/or-tools/pybind11-protobuf.nix
@@ -29,8 +29,15 @@ buildPythonPackage {
   ];
 
   postPatch = ''
+    # Original fix for version pinning
     substituteInPlace cmake/dependencies/CMakeLists.txt \
       --replace-fail 'find_package(protobuf 5.29.2 REQUIRED)' 'find_package(protobuf REQUIRED)'
+
+    # Fix for Protobuf 34.0 (absl::string_view migration)
+    substituteInPlace pybind11_protobuf/proto_cast_util.cc \
+      --replace-fail "const std::string& filename" "absl::string_view filename" \
+      --replace-fail "const std::string& symbol_name" "absl::string_view symbol_name" \
+      --replace-fail "const std::string& containing_type" "absl::string_view containing_type"
   '';
 
   nativeBuildInputs = [ cmake ];