anchor.diff:        serviceConfig = {
           Name = "net.connman.vpn";
           before = [ "connman" ];
  -        ExecStart = "${pkgs.connman}/sbin/connman-vpnd -n";
  +        ExecStart = "${cfg.package}/sbin/connman-vpnd -n";
           User = "root";
           SystemdService = "connman-vpn.service";
         };
  
positive.code:       message = "You can not use services.connman with networking.networkmanager";
      }];
  
      environment.systemPackages = [ connman ];
  
      systemd.services.connman = {
        description = "Connection service";
  
negative.code:         BusName = "net.connman";
          Restart = "on-failure";
          ExecStart = toString ([
            "${cfg.package}/sbin/connmand"
            "--config=${configFile}"
            "--nodaemon"
          ] ++ optional enableIwd "--wifi=iwd_agent"
  