anchor.diff:  { stdenv, lib, callPackage, fetchurl, unzip, atomEnv, makeDesktopItem,
  -  makeWrapper, libXScrnSaver }:
  +  makeWrapper, libXScrnSaver, libxkbfile }:
   
   let
     version = "1.11.1";
  
positive.code:   }.${stdenv.system};
  
    archive_fmt = if stdenv.system == "x86_64-darwin" then "zip" else "tar.gz";
  
  in
    stdenv.mkDerivation rec {
  
negative.code: 
      buildInputs = if stdenv.system == "x86_64-darwin"
        then [ unzip makeWrapper libXScrnSaver ]
        else [ makeWrapper libXScrnSaver libxkbfile ];
  
      installPhase =
        if stdenv.system == "x86_64-darwin" then ''
  