anchor.diff:      NewNodes = [{Node, joinning}|State#state.nodes],
       % TODO: health checks, if 'Node' is healthy, node status changes 
       %       alive.
  -    {noreply, NewNodes};
  +    {noreply, State#state{nodes = NewNodes}};
   handle_cast(_Msg, State) ->
       {noreply, State}.
   
  
positive.code: %%                                   {stop, Reason, State}
  %% @end
  %%--------------------------------------------------------------------
  handle_call({add, _Task, _Schedule, _Detail}, _From, State) ->
      Reply = ok,
      {reply, Reply, State};
  handle_call({cancel, _Task}, _From, State) ->
      Reply = ok,
      {reply, Reply, State};
  
negative.code: -define(SERVER, ?MODULE).
  
  -record(state, {
            nodes = [{node(), alive}] :: [{node(), term()}],
            tasks = [] :: [task()]
           }).
  
  -type task_name() :: binary().
  %% TODO: specifies the proprietary schedule time format.
  -type schedule() :: term().
  -type detail() :: binary().
  -type task() :: dict:dict(task_name(), {schedule(), detail()}).
  
  %%%===================================================================
  %%% API
  