anchor.diff:  
       case Message of
           undefined ->
  +            %% Store for reliability, if necessary.
  +            case proplists:get_value(ack, Options, false) of
  +                false ->
  +                    ok;
  +                true ->
  +                    %% Acknowledgements.
  +                    RescheduleableMessage = {forward_message, From, Name, Channel, MessageClock, PartitionKey, ServerRef, OriginalMessage, Options},
  +                    partisan_acknowledgement_backend:store(MessageClock, RescheduleableMessage)
  +            end,
  +
               %% Fire post-interposition functions.
               PostFoldFunUndefined = fun(_Name, PostInterpositionFun, ok) ->
                   PostInterpositionFun({forward_message, Name, OriginalMessage}, {forward_message, Name, Message}),
  
positive.code:                           membership_strategy_state=MembershipStrategyState,
                            connections=Connections}};
  
  handle_info(retransmit, #state{connections=Connections}=State) ->
      RetransmitFun = fun({_, {forward_message, Name, Channel, Clock, PartitionKey, ServerRef, Message, _Options}}) ->
          Mynode = partisan_peer_service_manager:mynode(),
          lager:info("~p restranmitting message ~p with clock ~p to ~p", [Mynode, Message, Clock, Name]),
  
          do_send_message(Name,
                          Channel,
                          PartitionKey,
                          {forward_message, ServerRef, Message},
                          Connections)
      end,
      {ok, Outstanding} = partisan_acknowledgement_backend:outstanding(),
      lager:info("~p outstanding messages are: ~p", [node(), Outstanding]),
  
negative.code: 
              lager:info("~p: Message after send interposition is: ~p", [node(), Message]),
  
              case From of 
                  undefined ->
                      ok;
                  _ ->
                      gen_server:reply(From, ok)
              end,
  
              {noreply, State#state{vclock=VClock}};
          Message ->
  