anchor.diff:      optipng
       inkscape
       gtk3
  -    gnome3.gnome-shell
     ];
   
     propagatedUserEnvPkgs = [
  
positive.code: 
  stdenv.mkDerivation rec {
    pname = "arc-theme";
    version = "20190330";
  
    src = fetchFromGitHub {
      owner  = "NicoHood";
      repo   = pname;
      rev    = version;
      sha256 = "16n5svgkpa8azxgyy64zwjjc04r57wfzkdq9igqvbvwkbvx8aa89";
    };
  
    nativeBuildInputs = [
  
negative.code: 
    enableParallelBuilding = true;
  
    preBuild = ''
      # Shut up inkscape's warnings about creating profile directory
      export HOME="$NIX_BUILD_ROOT"
    '';
  
    configureFlags = [
      "--with-gnome-shell=${stdenv.lib.versions.majorMinor gnome3.gnome-shell.version}"
      "--disable-unity"
    ];
  
    postInstall = ''
      install -Dm644 -t $out/share/doc/${pname} AUTHORS *.md
    '';
  
    meta = with stdenv.lib; {
      description = "Flat theme with transparent elements for GTK 3, GTK 2 and Gnome Shell";
      homepage    = https://github.com/arc-design/arc-theme;
      license     = licenses.gpl3;
      maintainers = with maintainers; [ simonvandel romildo ];
      platforms   = platforms.linux;
  