anchor.diff:      % Create $SYS Topics
       emqttd_pubsub:create(<<"$SYS/brokers">>),
       [ok = create_topic(Topic) || Topic <- ?SYSTOP_BROKERS],
  -    %% CLI
  -    emqttd_ctl:register_cmd(broker, {?MODULE, cli}, []),
       % Tick
       {ok, #state{started_at = os:timestamp(),
                   heartbeat  = start_tick(1000, heartbeat),
  
positive.code: terminate(_Reason, #state{heartbeat = Hb, tick_tref = TRef}) ->
      stop_tick(Hb),
      stop_tick(TRef),
      emqttd_ctl:unregister_cmd(broker),
      ok.
  
  code_change(_OldVsn, State, _Extra) ->
  
negative.code:     datetime,     % Broker local datetime
      sysdescr      % Broker description
  ]).
  
  %%%=============================================================================
  %%% API
  