anchor.diff:      end;
   
   
  -run(put, KeyGen, ValueGen, #state{id = Id, concurrent = Concurrent} = State) ->
  -    Key = keygen_global_uniq(Id, Concurrent, KeyGen), 
  +run(put, KeyGen, ValueGen, #state{check_integrity = CI, id = Id, concurrent = Concurrent} = State) ->
  +    Key = keygen_global_uniq(CI, Id, Concurrent, KeyGen), 
       Val = ValueGen(),
       {NextUrl, S2} = next_url(State),
       Url = url(NextUrl, Key, State#state.path_params),
       case do_put(Url, [], Val) of
           ok ->
  -            case State#state.check_integrity of
  +            case CI of
                   true ->
                       LocalMD5 = erlang:md5(Val),
                       ets:insert(?ETS_BODY_MD5, {Key, LocalMD5});
  
positive.code:     end;
  
  
  run(delete, KeyGen, _ValueGen, #state{id = Id, concurrent = Concurrent} = State) ->
      Key = keygen_global_uniq(Id, Concurrent, KeyGen), 
      {NextUrl, S2} = next_url(State),
      case do_delete(url(NextUrl, Key, State#state.path_params)) of
          {not_found, _Url} ->
              {ok, S2};
          {ok, _Url, _Headers} ->
              case State#state.check_integrity of
                  true ->
                      ets:delete(?ETS_BODY_MD5, Key);
                  false -> void
  
negative.code:                   concurrent = Concurrent,
                    check_integrity = CI }}.
  
  keygen_global_uniq(false, _Id, _Concurrent, KeyGen) ->
      KeyGen();
  keygen_global_uniq(true, Id, Concurrent, KeyGen) ->
      Base = KeyGen(),
      Rem = Base rem Concurrent,
      Diff = Rem - Id,
      Base - Diff.
  
  run(get, KeyGen, _ValueGen, #state{check_integrity = CI, id = Id, concurrent = Concurrent} = State) ->
      Key = keygen_global_uniq(CI, Id, Concurrent, KeyGen), 
      {NextUrl, S2} = next_url(State),
      case do_get(url(NextUrl, Key, State#state.path_params)) of
          {not_found, _Url} ->
              {ok, S2};
          {ok, _Url, _Headers, Body} ->
              case CI of
                  true ->
                      case ets:lookup(?ETS_BODY_MD5, Key) of
                          [{_Key, LocalMD5}|_] ->
  