anchor.diff:  	Next = cronparser:next(Now,Spec),
   	Interval = calendar:datetime_to_gregorian_seconds(Next) - calendar:datetime_to_gregorian_seconds(Now),
   	timer:seconds(Interval).
  +
  +store(Db, Key, Value) -> eleveldb:put(Db, term_to_binary(Key), term_to_binary(Value), []).
  +
  +%exists(Db, Key) ->
  +%        case eleveldb:get(Db, term_to_binary(Key), []) of
  +%                {ok, _BinaryTerm}  -> true;
  +%                not_found         -> false
  +%        end.
  +%
  +%getIfExists(Db, Key) ->
  +%        case eleveldb:get(Db, term_to_binary(Key), []) of
  +%                {ok, BinaryTerm} -> {ok, binary_to_term(BinaryTerm)};
  +%                not_found         -> false
  +%        end.
  +
  +delete(Db, Key) ->
  +        eleveldb:delete(Db, term_to_binary(Key), []).
  +
  
positive.code: 	end,
  	{ok, Timer} = watchbin:new(1000, CallBack, ShardIdentifier),
  
  	ets:insert(maestro_core_shard_registry, {ShardIdentifier, self()}),
  
  	{ok, #{ shard => ShardIdentifier, timer => Timer, db => DBRef, filename => FileName }}.
  
  
  handle_call({add_timer, Name, Data}, _From, State) ->
  	lager:info("Adding timer [~s]", [Name]),
  	ok = schedule_job(Name, Data, State),
  	{reply, ok, State};
  handle_call(_Msg, _From, State) ->
  
negative.code: %Next = cronparser:next(Now,Spec).
  %calendar:datetime_to_gregorian_seconds(Next) - calendar:datetime_to_gregorian_seconds(calendar:local_time()).
  
  schedule_job(Name, Data, #{ shard := Timer, db := Db }) ->
  	case determine_interval(Data) of
  		Interval when is_integer(Interval) andalso Interval > 0 ->
  			lager:info("Scheduling timer [~s] for ~B milliseconds", [Name, Interval]),
  			{ok, _} = watchbin:start_timer(Timer, Interval, #{ data => Data, name => Name }, [once, {name, Name}]);
  		_Undefined ->
  			lager:info("Timer [~s] not resecheduled: undefined next interval", [Name]),
  			delete(Db, Name)
  	end,
  	ok.
  
  determine_interval(#{ at := DateTime }) ->
  	Now = calendar:universal_time(),
  	Interval = calendar:datetime_to_gregorian_seconds(DateTime) - calendar:datetime_to_gregorian_seconds(Now),
  	timer:seconds(Interval);
  