anchor.diff:      sed -i -e "s|ecwolf.pk3|$out/share/ecwolf/ecwolf.pk3|" src/version.h
     ''
     # Disable app bundle creation on Darwin. It fails, and it is not needed to run it from the Nix store
  -  + lib.optionalString (stdenv.isDarwin) ''
  +  + lib.optionalString stdenv.isDarwin ''
       sed -i -e "s|include(\''${CMAKE_CURRENT_SOURCE_DIR}/macosx/install.txt)||" src/CMakeLists.txt
     '';
   
  
positive.code:     sha256 = "1sbdv672dz47la5a5qwmdi1v258k9kc5dkx7cdj2b6gk8nbm2srl";
    };
  
    nativeBuildInputs = [ cmake pkg-config ];
    buildInputs = [ zlib bzip2 libjpeg SDL SDL_mixer gtk2 copyDesktopItems ];
  
    desktopItems = [ desktopItem ];
  
    # Change the location where the ecwolf executable looks for the ecwolf.pk3
    # file.
  
negative.code: { stdenv, lib, fetchurl, makeDesktopItem, copyDesktopItems, cmake, pkg-config, zlib, bzip2, libjpeg, SDL, SDL_mixer, gtk2 }:
  
  stdenv.mkDerivation rec {
    pname = "ecwolf";
    version = "1.3.3";
  