diff --git a/pkgs/development/libraries/gtkmm/2.x.nix b/pkgs/development/libraries/gtkmm/2.x.nix
index 469c6adc6f7..69fd3f30e92 100644
--- a/pkgs/development/libraries/gtkmm/2.x.nix
+++ b/pkgs/development/libraries/gtkmm/2.x.nix
@@ -11,12 +11,14 @@ stdenv.mkDerivation rec {
 
   outputs = [ "out" "dev" ];
 
-  nativeBuildInputs = [pkgconfig];
+  nativeBuildInputs = [ pkgconfig ];
 
   propagatedBuildInputs = [ glibmm gtk2 atkmm cairomm pangomm ];
 
   doCheck = true;
 
+  enableParallelBuilding = true;
+
   meta = {
     description = "C++ interface to the GTK+ graphical user interface library";