anchor.diff:      list_to_binary(L).
   
   
  -%%
  -pmap(F, L) when is_function(F, 1), is_list(L) ->
  -    TaskId = {make_ref(), self()},
  -    [spawn(worker(TaskId, F, El)) || El <- tag(L)],
  -    collect(TaskId, length(L), []).
   tag(L) -> lists:zip(lists:seq(1, length(L)), L).
  -untag(L) -> [ Val || {_Ord, Val} <- lists:sort(L) ].
  -reply(Ord, {Ref, Pid}, Val) -> Pid ! {Ref, {Ord, Val}}.
  -worker(TaskId, Fun, {Ord, Item}) ->
  -    fun() ->
  -        Reply = try Fun(Item)
  -                catch Class:Reason ->
  -                    Stacktrace = erlang:get_stacktrace(),
  -                    escalus_ct:log_error("issue=pmap_failed reason=~p:~p~n"
  -                                         " stacktrace=~p",
  -                                         [Class, Reason, Stacktrace]),
  -                    {error, {Class, Reason}}
  -                end,
  -        reply(Ord, TaskId, Reply)
  -    end.
  -collect(_TaskId, 0, Acc) -> untag(Acc);
  -collect({Ref, _} = TaskId, N, Acc) ->
  -    receive {Ref, Val} -> collect(TaskId, N-1, [Val|Acc])
  -    after 5000 -> error({partial_results, Acc})
  -    end.
  
positive.code:     nasty_global_table() ! bye.
  clean() ->
      wpool:start_sup_pool(unregister_pool, [{workers, 10},
                                             {overrun_warning, 3000},
                                             {one_for_one, 3, 2}]), % if it dies 3 times in last 2 seconds, we fail
      L = ets:tab2list(nasty_global_table()),
      [wpool:cast(unregister_pool, {?MODULE, delete_users, [El]}, available_worker) || El <- tag(L)],
      ets:delete_all_objects(nasty_global_table()),
      ok.
  
  %%% Internals
  nasty_global_table() -> escalus_fresh_db.
  
  delete_users({_Suffix, Conf}) ->
      ct:pal("Deleting users..."),
      Plist = proplists:get_value(escalus_users, Conf),
      escalus_users:delete_users(Conf, Plist),
      ok.
  
  ensure_table_present(T) ->
      RunDB = fun() -> ets:new(T, [named_table, public]),
  
negative.code:          create_users/2,
           freshen_specs/2,
           freshen_spec/2,
           work_on_deleting_users/3, % used by wpool worker
           create_fresh_user/2]).
  -export([start/1,
           stop/1,
  