anchor.diff:  
       environment.systemPackages = [ cfg.package ];
   
  -    systemd.services = mkIf cfg.systemService {
  -      syncthing = header // {
  -        after = [ "network.target" ];
  +    systemd.services.syncthing = mkIf cfg.systemService
  +      header // {
           wantedBy = [ "multi-user.target" ];
           serviceConfig = service // {
             User = cfg.user;
  
positive.code:           ExecStart = "${cfg.package}/bin/syncthing -no-browser -home=${cfg.dataDir}";
          };
        };
      };
  
      systemd.user.services =  {
        syncthing = header // {
          serviceConfig = service // {
            ExecStart = "${cfg.package}/bin/syncthing -no-browser";
          };
        };
      };
    };
  }
  
negative.code: 
    header = {
      description = "Syncthing service";
      after = [ "network.target" ];
      environment = {
        STNORESTART = "yes";
        STNOUPGRADE = "yes";
  