anchor.diff:      system = pkgs.stdenv.system;
       allPackages = import ./pkgs/top-level/all-packages.nix;
     };
  +
  +  nix = pkgs.nixUnstable; # we need the exportReferencesGraph feature
   
   
     # Determine the set of modules that we need to mount the root FS.
  
positive.code:       pkgs.sysklogd
        pkgs.sysvinit
  #      pkgs.vim
        nixosInstaller
      ];
  
  
negative.code:   # The installer.
    nixosInstaller = import ./installer.nix {
      inherit (pkgs) stdenv genericSubstituter;
      inherit nix;
      nix = pkgs.nixUnstable; 
      shell = pkgs.bash + "/bin/sh";
    };
  
  