anchor.diff:  , configurationOverrides ? (config: {})
   # Whether to put all the build-time dependencies on DVD
   , includeBuildDeps ? false
  +, includeTarballs ? true
   }:
   
   rec {
  
positive.code:               tar xjf /install/nixos.tar.bz2 -C /etc/nixos/nixos
                mkdir -p /etc/nixos/nixpkgs
                tar xjf /install/nixpkgs.tar.bz2 -C /etc/nixos/nixpkgs
                chown -R root.root /etc/nixos
              end script
            ";
  
negative.code:       { source = system.config.boot.grubSplashImage;
          target = "boot/background.xpm.gz";
        }
      ]
      ++
      pkgs.lib.optionals includeTarballs [
        { source = nixosTarball + "/" + nixosTarball.tarName;
          target = "/install/" + nixosTarball.tarName;
        }
        { source = nixpkgsTarball + "/nixpkgs.tar.bz2";
          target = "/install/nixpkgs.tar.bz2";
        }
        { source = servicesTarball + "/services.tar.bz2";
          target = "/install/services.tar.bz2";
        }
      ];
  
  