anchor.diff:        script = ''
           while true; do
             echo -e "HTTP/1.1 200 OK\n\n $(<${fakeReply})\n" \
  -            | ${pkgs.netcat}/bin/nc -N -l 127.0.0.1 8332
  +            | ${pkgs.netcat}/bin/nc -N -l ::1 8332
           done
         '';
       };
  
positive.code:   };
  
    nodes.server = { ... }: {
      networking.nameservers = [ "127.0.0.1" ];
  
      services.namecoind.rpc = {
        address = "127.0.0.1";
        user = "namecoin";
        password = "secret";
        port = 8332;
  
negative.code:       identity.address    = "1.0.0.1";
      };
  
      services.pdns-recursor.enable = true;
      services.pdns-recursor.resolveNamecoin = true;
  
      environment.systemPackages = [ pkgs.dnsutils ];
    };
  
    testScript =
  