anchor.diff:              '';
             };
   
  +          persistentTimer = mkOption {
  +            default = false;
  +            type = types.bool;
  +            example = true;
  +            description = literalDocBook ''
  +              Set the <literal>persistentTimer</literal> option for the
  +              <citerefentry><refentrytitle>systemd.timer</refentrytitle>
  +              <manvolnum>5</manvolnum></citerefentry>
  +              which triggers the backup immediately if the last trigger
  +              was missed (e.g. if the system was powered down).
  +            '';
  +          };
  +
             user = mkOption {
               type = types.str;
               description = ''
  
positive.code:         # A repo named "foo" is mapped to systemd.services.borgbackup-repo-foo
          // mapAttrs' mkRepoService repos;
  
        users = mkMerge (mapAttrsToList mkUsersConfig repos);
  
        environment.systemPackages = with pkgs; [ borgbackup ] ++ (mapAttrsToList mkBorgWrapper jobs);
  
negative.code:       inherit (cfg) startAt;
      };
  
    mkBackupTimers = name: cfg:
      nameValuePair "borgbackup-job-${name}" {
        description = "BorgBackup job ${name} timer";
        timerConfig = {
          Persistent = cfg.persistentTimer;
        };
      };
  
    # utility function around makeWrapper
    mkWrapperDrv = {
        original, name, set ? {}
  