anchor.diff:        zlib
         libjpeg
         libsndfile
  +      libvpx
         mpg123
         game-music-emu
         zmusic
  
positive.code:     '';
  
      meta = with lib; {
        homepage = "https://github.com/coelckers/gzdoom";
        description =
          "A Doom source port based on ZDoom. It features an OpenGL renderer and lots of new features";
        license = licenses.gpl3;
        platforms = [ "x86_64-linux" ];
        maintainers = with maintainers; [ lassulus ];
      };
    };
  
  in gzdoom
  
negative.code: { lib, stdenv, fetchFromGitHub, cmake, makeWrapper, openal, fluidsynth
  , soundfont-fluid, libGL, SDL2, bzip2, zlib, libjpeg, libsndfile, libvpx, mpg123
  , game-music-emu, pkg-config, copyDesktopItems, makeDesktopItem }:
  
  let
    zmusic = stdenv.mkDerivation rec {
      pname = "zmusic";
      version = "1.1.3";
  
      src = fetchFromGitHub {
        owner = "ZDoom";
        repo = "ZMusic";
        rev = version;
        hash = "sha256-wrNWfTIbNU/S2qFObUSkb6qyaceh+Y7Loxqudl86+W4=";
      };
  
      nativeBuildInputs = [ cmake pkg-config ];
  
  