anchor.diff:          license = lib.licenses.asl20;
           platforms = lib.platforms.all;
           maintainers = with maintainers; [ thoughtpolice offline kamilchm illustris ];
  -      };
  +      } // extraMeta;
       };
   in
   {
  
positive.code:     pname = "spark";
      version = "2.4.8";
      sha256 = "1mkyq0gz9fiav25vr0dba5ivp0wh0mh7kswwnx8pvsmb6wbwyfxv";
    };
  }
  
negative.code: with lib;
  
  let
    spark = { pname, version, sha256, extraMeta ? {} }:
      stdenv.mkDerivation rec {
        inherit pname version;
        src = fetchzip {
  