diff --git a/pkgs/development/libraries/tk/generic.nix b/pkgs/development/libraries/tk/generic.nix
index 10b8bc7cd71..6e4640fabb7 100644
--- a/pkgs/development/libraries/tk/generic.nix
+++ b/pkgs/development/libraries/tk/generic.nix
@@ -20,6 +20,9 @@ stdenv.mkDerivation {
     ln -s $out/bin/wish* $out/bin/wish
     cp ../{unix,generic}/*.h $out/include
     ln -s $out/lib/libtk${tcl.release}.so $out/lib/libtk.so
+  ''
+  + stdenv.lib.optionalString (stdenv.isDarwin) ''
+    cp ../macosx/*.h $out/include
   '';
 
   configureFlags = [