anchor.diff:        { source = nixpkgsTarball + "/nixpkgs.tar.bz2";
           target = "/install/nixpkgs.tar.bz2";
         }
  -      { source = servicesTarball + "/services.tar.bz2";
  -        target = "/install/services.tar.bz2";
  -      }
       ];
   
       # Closures to be copied to the Nix store on the CD.
  
positive.code:   nixosTarball = makeTarball "nixos.tar.bz2" ../..;
  
  
    # Put Services in a tarball.
    servicesTarball = makeTarball "services.tar.bz2" services;
  
  
    # Put Nixpkgs in a tarball.
    nixpkgsTarball = makeTarball "nixpkgs.tar.bz2" nixpkgs;
  
  
negative.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
            ";
  