anchor.diff:      core = "play";
       description = "Port of Play! to libretro";
       license = lib.licenses.bsd2;
  -    extraBuildInputs = [ boost ];
  -    extraNativeBuildInputs = [ cmake openssl curl icu libGL libGLU xorg.libX11 ];
  -    makefile = "Makefile";
  -    cmakeFlags = [ "-DBUILD_PLAY=OFF -DBUILD_LIBRETRO_CORE=ON" ];
  -    postBuild = "mv Source/ui_libretro/play_libretro${stdenv.hostPlatform.extensions.sharedLibrary} play_libretro${stdenv.hostPlatform.extensions.sharedLibrary}";
  +    extraBuildInputs = [ boost bzip2 curl openssl icu libGL libGLU xorg.libX11 ];
  +    extraNativeBuildInputs = [ cmake ];
  +    makefile = "Makefile";
  +    cmakeFlags = [ "-DBUILD_PLAY=OFF" "-DBUILD_LIBRETRO_CORE=ON" ];
  +    postBuild = "cd Source/ui_libretro";
     };
   
     ppsspp = mkLibRetroCore {
  
positive.code:   };
  
    mesen-s = mkLibRetroCore {
      core = "mesens";
      src = getCoreSrc "mesen-s";
      description = "Port of Mesen-S to libretro";
      license = lib.licenses.gpl3Only;
      makefile = "Makefile";
      preBuild = "cd Libretro";
      postInstall = ''
        # fix library name to match libretro-core-info
        mv $coreDir/mesens_libretro${stdenv.hostPlatform.extensions.sharedLibrary} \
          $coreDir/mesen-s_libretro${stdenv.hostPlatform.extensions.sharedLibrary}
      '';
    };
  
    meteor = mkLibRetroCore {
  
negative.code: , alsa-lib
  , boost
  , buildPackages
  , bzip2
  , cmake
  , curl
  , fetchFromGitHub
  