anchor.diff:      end;
   export(traces, Tab, Resource, #state{protocol=grpc,
                                        grpc_metadata=Metadata,
  -                                     channel_pid=_ChannelPid}) ->
  +                                     channel=Channel}) ->
       ExportRequest = otel_otlp_traces:to_proto(Tab, Resource),
       Ctx = grpcbox_metadata:append_to_outgoing_ctx(ctx:new(), Metadata),
  -    case opentelemetry_trace_service:export(Ctx, ExportRequest, #{channel => ?MODULE}) of
  +    case opentelemetry_trace_service:export(Ctx, ExportRequest, #{channel => Channel}) of
           {ok, _Response, _ResponseMetadata} ->
               ok;
           {error, {Status, Message}, _} ->
  
positive.code:               endpoint/0,
                protocol/0]).
  
  -record(state, {protocol :: protocol(),
                  channel_pid :: pid() | undefined,
                  headers :: headers(),
                  compression :: compression() | undefined,
  
negative.code:     end;
  export(metrics, Tab, Resource, #state{protocol=grpc,
                                        grpc_metadata=Metadata,
                                        channel=Channel}) ->
      ExportRequest = otel_otlp_metrics:to_proto(Tab, Resource),
      Ctx = grpcbox_metadata:append_to_outgoing_ctx(ctx:new(), Metadata),
      case opentelemetry_metrics_service:export(Ctx, ExportRequest, #{channel => Channel}) of
          {ok, _Response, _ResponseMetadata} ->
              ok;
          {error, {Status, Message}, _} ->
  