anchor.diff:          group = "smtpq";
         };
       };
  +
  +    security.wrappers.smtpctl = {
  +      group = "smtpq";
  +      setgid = true;
  +      source = "${cfg.package}/bin/smtpctl";
  +    };
  +
  +    services.mail.sendmailSetuidWrapper = mkIf cfg.setSendmail security.wrappers.smtpctl;
   
       systemd.tmpfiles.rules = [
         "d /var/spool/smtpd 711 root - - -"
  
positive.code: 
    ###### implementation
  
    config = mkIf cfg.enable {
      users.groups = {
        smtpd.gid = config.ids.gids.smtpd;
        smtpq.gid = config.ids.gids.smtpq;
  
negative.code:         description = "The OpenSMTPD package to use.";
        };
  
        setSendmail = mkOption {
          type = types.bool;
          default = true;
          description = "Whether to set the system sendmail to OpenSMTPD's.";
        };
  
        extraServerArgs = mkOption {
  