anchor.diff:    Since = maps:get(since, Options, 0),
     ChangeCb = maps:get(changes_cb, Options, nil),
     Mode = maps:get(mode, Options, binary),
  -  
  +
     %% make change callback
     ChangeFun = case {Mode, ChangeCb} of
                   {binary, nil} ->
  
positive.code:     Opts
    ),
    State#{ last_seq => LastSeq1, changes => Changes1}.
    
  
  parse_options(Options) ->
    maps:fold(
  
negative.code:   ).
  
  encode_sse(Change) ->
    Seq = maps:get(<<"seq">>, Change),
    << "id: ", (integer_to_binary(Seq))/binary, "\n",
       "data: ", (jsx:encode(Change))/binary >>.
  