diff --git a/pkgs/os-specific/darwin/swift-corelibs/corefoundation.nix b/pkgs/os-specific/darwin/swift-corelibs/corefoundation.nix
index bfe862eb3957..7c48d695e11d 100644
--- a/pkgs/os-specific/darwin/swift-corelibs/corefoundation.nix
+++ b/pkgs/os-specific/darwin/swift-corelibs/corefoundation.nix
@@ -11,7 +11,8 @@ let
 in
 
 stdenv.mkDerivation {
-  name = "swift-corefoundation";
+  pname = "swift-corefoundation";
+  version = "unstable-2018-09-14";
 
   src = fetchFromGitHub {
     owner  = "apple";