anchor.diff:  -spec qwrite_fast(pid_groups:pidname(),
                     comm:erl_local_pid(),
                     ?RT:key(),
  -                  fun ((any(), any(), any()) -> any()), %% CC (Content Check)
  +                  fun ((any(), any(), any()) -> {boolean(), any()}), %% CC (Content Check)
                     client_value(), prbr:r_with_id(),
                     client_value() | prbr_bottom) -> ok.
   qwrite_fast(CSeqPidName, Client, Key, CC, Value, Round, OldVal) ->
  
positive.code:              comm:erl_local_pid(),
               ?RT:key(),
               fun ((any()) -> any()), %% read filter
               fun ((any(), any(), any()) -> any()), %% content check
               fun ((any(), any(), any()) -> any()), %% write filter
  %%              %% select what you need to read for the operation
  %%              fun ((CustomData) -> ReadInfo),
  
negative.code: -spec qwrite(pid_groups:pidname(),
               comm:erl_local_pid(),
               ?RT:key(),
               fun ((any(), any(), any()) -> {boolean(), any()}), %% CC (Content Check)
               client_value()) -> ok.
  qwrite(CSeqPidName, Client, Key, CC, Value) ->
      RF = fun prbr:noop_read_filter/1,
  