anchor.diff:      gen_server:call(?MODULE, {receive_message, FullMessage}, infinity);
   receive_message({forward_message, ServerRef, {'$partisan_padded', _Padding, Message}}) ->
       receive_message({forward_message, ServerRef, Message});
  +receive_message({forward_message, _ServerRef, {causal, Label, _, _, _, _, _} = Message}) ->
  +    partisan_causality_backend:receive_message(Label, Message);
   receive_message({forward_message, ServerRef, Message}) ->
  -    %% Deliver the message.
  -    try
  -        ServerRef ! Message
  -    catch
  -        _:Error ->
  -            lager:error("Error forwarding message ~p to process ~p: ~p", [Message, ServerRef, Error])
  -    end,
  -
  -    ok;
  +    process_forward(ServerRef, Message);
   receive_message(Message) ->
       gen_server:call(?MODULE, {receive_message, Message}, infinity).
   
  
positive.code:                     {ack, MessageClock},
                      Connections),
  
      %% Attempt message delivery.
      try
          ServerRef ! Message
      catch
          _:Error ->
              lager:debug("Error forwarding message ~p to process ~p: ~p", [Message, ServerRef, Error])
      end,
      {reply, ok, State};
  handle_message({forward_message, ServerRef, Message}, State) ->
      try
          ServerRef ! Message
      catch
          _:Error ->
              lager:debug("Error forwarding message ~p to process ~p: ~p", [Message, ServerRef, Error])
      end,
      {reply, ok, State};
  handle_message({ack, MessageClock}, State) ->
      partisan_reliability_backend:ack(MessageClock),
      {reply, ok, State}.
  
  %% @private
  schedule_gossip() ->
  
negative.code:                     {stop, normal, State#state{membership=EmptyMembership}}
              end
      end;
  handle_message({forward_message, SourceNode, MessageClock, ServerRef, {causal, Label, _, _, _, _, _} = Message},
                 #state{connections=Connections}=State) ->
      %% Try to acknowledge.
      do_send_message(SourceNode,
  