anchor.diff:      end.
   
   aggregate_metrics(#s{nodes = Nodes, metric_groups = MetricGroups, histograms = Histograms} = State) ->
  -    system_log:info("[ metrics ] METRIC AGGREGATION:"),
       StartTime = os:timestamp(),
   
       Values = mzb_lists:pmap(
  
positive.code:     system_log:info("[ metrics ] CHECK SIGNALS:"),
      RawSignals = mzb_lists:pmap(
          fun (N) ->
              system_log:info("[ metrics ] Reading signals from ~p...", [N]),
              case mzb_interconnect:call(N, get_all_signals) of
                  {badrpc, Reason} ->
                      system_log:error("[ metrics ] Failed to request signals from node ~p (~p)", [N, Reason]),
                      [];
                  Res ->
                      system_log:info("[ metrics ] Received signals from ~p", [N]),
                      Res
              end
          end, lists:usort([erlang:node()] ++ Nodes)),
  
negative.code:     State#s{histograms = NewHistograms}.
  
  evaluate_derived_metrics(#s{metric_groups = MetricGroups} = State) ->
      NewState = eval_rps(State),
  
      DerivedMetrics = lists:filter(fun is_derived_metric/1, extract_metrics(MetricGroups)),
      lists:foreach(fun ({Name, derived, #{resolver:= Resolver, worker:= {Provider, Worker}}}) ->
          try Provider:apply(Resolver, [], Worker) of
  