anchor.diff:          # Allow the machine to talk to the fake nixos.org.
           $machine->succeed(
               "rm /etc/hosts",
  -            "echo 192.168.1.1 nixos.org cache.nixos.org > /etc/hosts",
  +            "echo 192.168.1.1 nixos.org cache.nixos.org tarballs.nixos.org > /etc/hosts",
               "ifconfig eth1 up 192.168.1.2",
           );
   
  
positive.code:         $webserver->succeed(
              "nix-push --bzip2 --dest /tmp/channel --manifest --url-prefix http://nixos.org/channels/nixos-unstable " .
              "${toString channelContents} >&2");
        ''}
  
        # Make sure that we get a login prompt etc.
  
negative.code:         };
  
        virtualisation.writableStore = true;
        virtualisation.pathsInNixDB = channelContents ++ [ pkgs.hello.src ];
        virtualisation.memorySize = 768;
      };
  
    channelContents = [ pkgs.rlwrap ];
  
  
    # The test script boots the CD, installs NixOS on an empty hard
  