diff --git a/pkgs/development/python-modules/llama-cpp-python/default.nix b/pkgs/development/python-modules/llama-cpp-python/default.nix
index 6c07005d4ddf..09ee66b8caf0 100644
--- a/pkgs/development/python-modules/llama-cpp-python/default.nix
+++ b/pkgs/development/python-modules/llama-cpp-python/default.nix
@@ -71,6 +71,10 @@ buildPythonPackage rec {
     ]
   );
 
+  preBuild = ''
+    export CMAKE_BUILD_PARALLEL_LEVEL="$NIX_BUILD_CORES"
+  '';
+
   nativeBuildInputs = [
     cmake
     ninja