anchor.diff:  
   -define(FILENAME, "zones.json").
   
  -% Public API
  +%% Public API
   
   %% @doc Load zones from a file. The default file name is "zones.json".
   -spec load_zones() -> {ok, integer()} | {err,  atom()}.
  
positive.code:             {err, Reason}
      end.
  
  % Internal API
  filename() ->
      case application:get_env(erldns, zones) of
          {ok, Filename} -> Filename;
  
negative.code:             JsonZones = jsx:decode(Binary),
              erldns_log:info("Putting zones into cache"),
              lists:foreach(
                fun(JsonZone) ->
                        Zone = erldns_zone_parser:zone_to_erlang(JsonZone),
                        erldns_zone_cache:put_zone(Zone)
                end, JsonZones),
              erldns_log:info("Loaded ~p zones", [length(JsonZones)]),
              {ok, length(JsonZones)};
          {error, Reason} ->
  