anchor.diff:  , configurationOverrides ? (config: {})
   # Whether to put all the build-time dependencies on DVD
   , includeBuildDeps ? false
  +, includeTarballs ? true
   }:
   
   rec {
  
positive.code:       { source = system.config.boot.grubSplashImage;
          target = "boot/background.xpm.gz";
        }
        { source = nixosTarball + "/" + nixosTarball.tarName;
          target = "/install/" + nixosTarball.tarName;
        }
        { source = nixpkgsTarball + "/nixpkgs.tar.bz2";
          target = "/install/nixpkgs.tar.bz2";
        }
      ];
  
  
negative.code:     else "nixos-${builtins.readFile ../../VERSION}"
  , compressImage ? false
  , nixpkgs ? ../../../nixpkgs
  , services ? ../../../services
  # This option allows easy building of Rescue CD with 
  # modified package set / driver set / anything.
  # For easier maitenance, let overrider know the current
  