diff --git a/pkgs/development/libraries/qt-5/mkDerivation.nix b/pkgs/development/libraries/qt-5/mkDerivation.nix
index ef105092fe2..385ebeacd8f 100644
--- a/pkgs/development/libraries/qt-5/mkDerivation.nix
+++ b/pkgs/development/libraries/qt-5/mkDerivation.nix
@@ -21,7 +21,7 @@ let
           (if debug then "-DCMAKE_BUILD_TYPE=Debug"
                     else "-DCMAKE_BUILD_TYPE=Release");
 
-    enableParallelBuilding = args.enableParallelBuilding or false;
+    enableParallelBuilding = args.enableParallelBuilding or true;
 
   };
 in