anchor.diff:      [{parallelism, 1}, {channels, []}] ++ Config;
   init_per_group(with_causal_labels, Config) ->
       [{causal_labels, [default]}] ++ Config;
  +init_per_group(with_ack, Config) ->
  +    [{forward_options, [{ack, true}]}] ++ Config;
   init_per_group(with_tls, Config) ->
       TLSOpts = make_certs(Config),
       [{parallelism, 1}, {tls, true}] ++ TLSOpts ++ Config;
  
positive.code:       [{simple, [shuffle]},
         {hyparview, [shuffle]}
        ]},
  
       {group, with_causal_labels, []},
  
  
negative.code:        hyparview_manager_high_active_test,
         hyparview_manager_low_active_test,
         hyparview_manager_high_client_test]},
  
       {with_ack, [],
        [default_manager_test]},
  
       {with_causal_labels, [],
        [causal_test]},
  