anchor.diff:  handle_event({log, Message}, #state{handle = Handle, level = Level, formatter = Formatter, format_config = FormatConfig} = State) ->
       case lager_util:is_loggable(Message, Level, State#state.id) of
           true ->
  -            nt_eventlog:report_event(Handle, Level, Formatter:format(Message, FormatConfig)),
  +            nt_eventlog:report_event(Handle, lager_msg:severity_as_int(Message), Formatter:format(Message, FormatConfig)),
               {ok, State};
           false ->
               {ok, State}
  
positive.code:     {ok, State}.
  
  config_to_id([Source | _]) ->
      {?MODULE, Source}.
negative.code: init([Source, Level]) ->
      init([Source, Level, {lager_default_formatter, ?DEFAULT_FORMAT}]);
  init([Source, Level, {Formatter, FormatterConfig}]) ->
      case parse_level(Level) of
          {ok, Lvl} ->
              case nt_eventlog:register_event_source(Source) of
                  {ok, Handle} ->
                      {ok, #state{id = {?MODULE, Source},
                                  level = Lvl,
                                  handle = Handle,
                                  formatter = Formatter,
                                  format_config = FormatterConfig}};
                  Error ->
                      Error
              end;
          Error ->
              Error
      end.
  