anchor.diff:      license = "MAME";
       makefile = "Makefile";
       makeFlags = lib.optional (!stdenv.hostPlatform.isx86) "IS_X86=0";
  +    enableParallelBuilding = false;
     };
   
     mame2003 = mkLibRetroCore {
  
positive.code:     description = "Port of MAME ~2003 to libretro";
      license = "MAME";
      makefile = "Makefile";
    };
  
    mame2003-plus = mkLibRetroCore {
  
negative.code:       # make -C 3rdparty/genie/build/gmake.linux -f genie.make obj/Release/src/host/lua-5.3.0/src/lgc.o
        mkdir -p 3rdparty/genie/build/gmake.linux/obj/Release/src/host/lua-5.3.0/src
      '';
      enableParallelBuilding = false;
    };
  
    mesen = mkLibRetroCore {
  