diff --git a/pkgs/development/python-modules/llama-cpp-python/default.nix b/pkgs/development/python-modules/llama-cpp-python/default.nix
index f7137c0778ee..8f9b293a7ba9 100644
--- a/pkgs/development/python-modules/llama-cpp-python/default.nix
+++ b/pkgs/development/python-modules/llama-cpp-python/default.nix
@@ -56,6 +56,10 @@ buildPythonPackage rec {
     ]
   );
 
+  preBuild = ''
+    export CMAKE_BUILD_PARALLEL_LEVEL="$NIX_BUILD_CORES"
+  '';
+
   nativeBuildInputs = [
     cmake
     ninja