anchor.diff:    buildInputs = (with xorg; [
       libXdamage libXtst libXScrnSaver libxkbfile
     ]) ++ [
  -    gtk2 gnome2.GConf nss alsaLib
  +    gtk3 nss alsaLib
     ];
     runtimeDependencies = [ udev.lib libnotify ];
   
  
positive.code: { stdenv, fetchurl, rpmextract, autoPatchelfHook
  , xorg, gtk2, gnome2, nss, alsaLib, udev, libnotify }:
  
  let
    version = "4.0.1";
  in stdenv.mkDerivation {
    pname = "vk-messenger";
    inherit version;
    src = {
      i686-linux = fetchurl {
        url = "https://desktop.userapi.com/rpm/master/vk-${version}.i686.rpm";
        sha256 = "0mgppa9qnhix64zp40dc05yc9klsc7qiwcgw7pwq2wm7m3fz3nm8";
      };
      x86_64-linux = fetchurl {
        url = "https://desktop.userapi.com/rpm/master/vk-${version}.x86_64.rpm";
        sha256 = "0ra0y4dfx4gfa1r3lm6v42j7c9pf7a8vh12kxv3wkg3pvijwgdsm";
      };
    }.${stdenv.system} or (throw "Unsupported system: ${stdenv.system}");
  
  
negative.code:     license = licenses.unfree;
      maintainers = [ maintainers.gnidorah ];
      platforms = ["i686-linux" "x86_64-linux"];
    };
  }
  