anchor.diff:  { stdenv, fetchurl, makeDesktopItem, makeWrapper
  -, jdk, jre, libpulseaudio
  +, jdk, jre, libpulseaudio, libXxf86vm
   }:
   
   let
  
positive.code:     genericName = "minecraft";
      categories = "Game;";
    };
  
  in stdenv.mkDerivation {
    name = "minecraft-2015-07-24";
  
negative.code: 
      makeWrapper ${jre}/bin/java $out/bin/minecraft \
        --add-flags "-jar $out/share/minecraft/minecraft.jar" \
        --suffix LD_LIBRARY_PATH : ${libPath}
  
      cp $src $out/share/minecraft/minecraft.jar
      cp -r ${desktopItem}/share/applications $out/share
  