anchor.diff:          true -> error(term_to_big);
           false -> ok
       end,
  -    case exec(?DRIVER, set, to_driver_key(Bucket, Key), to_binary(Value), 0) of
  +    case exec(?DRIVER, set, to_driver_key(Bucket, Key), to_json(Value), 0) of
           ok ->
               {ok, Key};
           {ok, _} ->
  
positive.code:         true -> error(term_to_big);
          false -> ok
      end,
      case exec(?DRIVER, add, to_driver_key(Bucket, Key), to_binary(Value), 0) of
          ok ->
              {ok, Key};
          {ok, _} ->
  
negative.code:             {error, Reason};
          {ok, {CAS, Value}} ->
              {ok, #document{key = Key, rev = CAS,
                  value = from_json(Value)}};
          {ok, Value} ->
              {ok, #document{key = Key, value = from_json(Value)}}
      end.
  
  
  