anchor.diff:      AggregationModule = aggregation_module(Instrument, View, Reader),
       Temporality = maps:get(Kind, ReaderTemporalityMapping),
   
  -    ViewAggregationReader = ViewAggregation#view_aggregation{
  -                              reader_pid=Pid,
  -                              aggregation_module=AggregationModule,
  -                              temporality=Temporality},
  -
  -    %% ets:insert(?VIEW_AGGREGATIONS_TAB, ViewAggregationReader),
  -
  -    ViewAggregationReader.
  +    ViewAggregation#view_aggregation{
  +      reader_pid=Pid,
  +      aggregation_module=AggregationModule,
  +      temporality=Temporality}.
   
   %% no aggregation defined for the View, so get the aggregation from the Reader
   %% the Reader's mapping of Instrument Kind to Aggregation was merged with the
  
positive.code: -spec aggregation_module(otel_instrument:t(), otel_view:t(), reader()) -> module().
  aggregation_module(#instrument{kind=Kind}, #view{aggregation_module=undefined},
                     #reader{default_aggregation_mapping=ReaderAggregationMapping}) ->
      ct:pal("Mapping ~p", [ReaderAggregationMapping]),
      maps:get(Kind, ReaderAggregationMapping);
  aggregation_module(_Instrument, #view{aggregation_module=Module}, _Reader) ->
      Module.
  
negative.code:                    Views) ->
      ViewMatches = otel_view:match_instrument_to_views(Instrument, Views),
      lists:map(fun(Reader=#reader{view_aggregation_tab=ViewAggregationTab}) ->
                        case ets:lookup(ViewAggregationTab, Instrument) of
                            [] ->
                                %% this instrument hasn't been seen before
                                Matches = per_reader_aggregations(Reader, Instrument, ViewMatches),
                                true = ets:insert(ViewAggregationTab, {Instrument, Matches}),
                                update_aggregations(Measurement, Reader, Matches);
                            [{_, Matches}] ->
                                %% TODO: matches need to be  updated when a new view is added
                                update_aggregations(Measurement, Reader, Matches)
                        end
                end, Readers).
  
  update_aggregations(#measurement{attributes=Attributes,
  