diff --git a/nix/zig.nix b/nix/zig.nix
index f4fd935..3f448a1 100644
--- a/nix/zig.nix
+++ b/nix/zig.nix
@@ -1,12 +1,21 @@
 { pkgs }:
 
+let
+  nixpkgsWithLLVM13_0_1 = pkgs.fetchFromGitHub {
+    owner = "TerrorJack";
+    repo = "nixpkgs";
+    rev = "1a8754caf8eb8831b904daaf34b2ee737053b383";
+    sha256 = "jmZIAMpm5wPw1QclgA6jsgMbN5MinakuXtUFHZWd5kY=";
+  };
+  pkgsFork = import nixpkgsWithLLVM13_0_1 { system = pkgs.system; };
+in
 pkgs.mkShell {
   buildInputs = with pkgs; [
     cmake
     ninja
-    llvmPackages_13.clang-unwrapped
-    llvmPackages_13.llvm
-    llvmPackages_13.lld
+    pkgsFork.llvmPackages_13.clang-unwrapped
+    pkgsFork.llvmPackages_13.llvm
+    pkgsFork.llvmPackages_13.lld
     libxml2
     zlib
   ];