anchor.diff:  -export([
   	init_tables/0,
   	subscribe/1,
  +	subscribe/2,
   	send/2
   ]).
   
  
positive.code: 	{ok, #{ subscribers => [] }}.
  
  handle_call({subscribe, Topics}, {From, _}, #{ subscribers := Subs } = State) ->
  	NewSubs = case lists:keyfind(From, 1, Subs) of
  		{From, _MonRef} -> Subs;
  		false          ->
  			MonRef = monitor(process, From),
  			[{From, MonRef} |Subs]
  	end,
  	true = ets:insert(?MODULE, [{Topic, From} || Topic <- Topics]),
  	{reply, ok, State#{ subscribers :=  NewSubs }};
  handle_call(_Request, _From, State) ->
  	{reply, ok, State}.
  
negative.code: send_event(Message, From, {Topic, Subscriber}) ->
  	Subscriber ! {hot_proxy_event, From, {Topic, Message}},
  	ok.
  
  ensure_monitor(New, Existing) when is_pid(New) ->
  	case lists:keyfind(New, 1, Existing) of
  		{New, _MonRef} -> Existing;
  		false          ->
  			MonRef = monitor(process, New),
  			[{New, MonRef} |Existing]
  	end.
  