anchor.diff:  
     config = mkIf config.services.kerberos_server.enable {
   
  -    environment.systemPackages = [ heimdal ];
  +    environment.systemPackages = [ heimdalFull ];
   
       services.xinetd.enable = true;
       services.xinetd.services = lib.singleton
  
positive.code: 
    inherit (lib) mkOption mkIf singleton;
  
    inherit (pkgs) heimdal;
  
    stateDir = "/var/heimdal";
  in
  
negative.code:         protocol = "tcp";
          user = "root";
          server = "${pkgs.tcp_wrappers}/sbin/tcpd";
          serverArgs = "${pkgs.heimdalFull}/sbin/kadmind";
        };
  
      systemd.services.kdc = {
  