anchor.diff: -{ lib, stdenv
  +{ lib
  +, stdenv
   , fetchurl
   , dpkg
   , undmg
  
positive.code:       xorg.libXi
        xorg.libXrandr
        xorg.libXrender
        xorg.libxshmfence
        xorg.libXtst
        xorg.libxkbfile
      ] + ":${stdenv.cc.cc.lib}/lib64";
  
      buildInputs = [
        gtk3  # needed for GSETTINGS_SCHEMAS_PATH
      ];
  
      nativeBuildInputs = [ dpkg makeWrapper nodePackages.asar ];
  
negative.code:       /usr/bin/defaults write com.tinyspeck.slackmacgap SlackNoAutoUpdates -bool YES
      '';
    };
  in
  if stdenv.isDarwin
  then darwin
  else linux
  