anchor.diff:  
   end_per_testcase(_, _) ->
       ok.
  +
  +%% replace/2
  +
  +replace(Pairs, Config)
  +  when is_list(Pairs) ->
  +    lists:foldl(fun replace/2, Config, Pairs);
  +
  +replace({Key, _} = T, Config) ->
  +    [T | lists:keydelete(Key, 1, Config)].
   
   %% --------------------
   
  
positive.code:         false ->
              start_services(Config),
              add_transports(Config),
              [{sleep, Name == parallel} | Config]
      end;
  
  init_per_group(sctp = Name, Config) ->
  
negative.code:                        server_decoding = D,
                         server_sender = SS,
                         server_throttle = ST},
              replace([{group, G}, {runlist, select()}], Config);
          _ ->
              Config
      end.
  