diff --git a/codex-rs/default.nix b/codex-rs/default.nix
index 8ad019a1d..c9586128e 100644
--- a/codex-rs/default.nix
+++ b/codex-rs/default.nix
@@ -1,4 +1,6 @@
 {
+  cmake,
+  llvmPackages,
   openssl,
   rustPlatform,
   pkg-config,
@@ -15,8 +17,11 @@ rustPlatform.buildRustPackage (_: {
   doCheck = false;
   src = ./.;
   nativeBuildInputs = [
-    pkg-config
+    cmake
+    llvmPackages.clang
+    llvmPackages.libclang.lib
     openssl
+    pkg-config
   ];
 
   cargoLock.outputHashes = {
@@ -25,8 +30,8 @@ rustPlatform.buildRustPackage (_: {
     "nucleo-0.5.0" = "sha256-Hm4SxtTSBrcWpXrtSqeO0TACbUxq3gizg1zD/6Yw/sI=";
     "nucleo-matcher-0.3.1" = "sha256-Hm4SxtTSBrcWpXrtSqeO0TACbUxq3gizg1zD/6Yw/sI=";
     "runfiles-0.1.0" = "sha256-uJpVLcQh8wWZA3GPv9D8Nt43EOirajfDJ7eq/FB+tek=";
-    "tokio-tungstenite-0.28.0" = "sha256-vJZ3S41gHtRt4UAODsjAoSCaTksgzCALiBmbWgyDCi8=";
-    "tungstenite-0.28.0" = "sha256-CyXZp58zGlUhEor7WItjQoS499IoSP55uWqr++ia+0A=";
+    "tokio-tungstenite-0.28.0" = "sha256-hJAkvWxDjB9A9GqansahWhTmj/ekcelslLUTtwqI7lw=";
+    "tungstenite-0.27.0" = "sha256-AN5wql2X2yJnQ7lnDxpljNw0Jua40GtmT+w3wjER010=";
   };
 
   meta = with lib; {