anchor.diff:      BaseClockVector = dict:store(Lid, NewN, ClockVector),
       LidsClockVector = recent_dependency_cv(Selected, BaseClockVector, LidTrace),
       NewClockMap = dict:store(Lid, LidsClockVector, ClockMap),
  -    NewSleepSetCandidates =
  -        ordsets:union(ordsets:del_element(Lid, Done), SleepSet),
  -    NewSleepSet = filter_awaked(NewSleepSetCandidates, Nexts, Selected),
  +    NewSleepSet =
  +        case Flavor of
  +            fake -> [];
  +            _Other ->
  +                NewSleepSetCandidates =
  +                    ordsets:union(ordsets:del_element(Lid, Done), SleepSet),
  +                filter_awaked(NewSleepSetCandidates, Nexts, Selected)
  +        end,
       NewNexts = dict:store(Lid, Next, Nexts),
       MaybeNotPollable = ordsets:del_element(Lid, Pollable),
       {NewPollable, NewEnabled, NewBlocked} =
  
positive.code: %% - wait any possible additional messages
  %% - check for async
  update_trace({Lid, _} = Selected, Next, State) ->
      #dpor_state{trace = [PrevTraceTop|Rest]} = State,
      #trace_state{i = I, enabled = Enabled, blocked = Blocked,
                   pollable = Pollable, done = Done,
                   nexts = Nexts, lid_trace = LidTrace,
  
negative.code:     end.
  
  add_some_next_to_backtrack(State) ->
      #dpor_state{trace = [TraceTop|Rest], dpor_flavor = Flavor,
                  preemption_bound = PreBound} = State,
      #trace_state{enabled = Enabled, sleep_set = SleepSet,
                   error_nxt = ErrorNext, last = {Lid, _},
                   preemptions = Preemptions} = TraceTop,
      ?f_debug("Pick random: Enabled: ~w Sleeping: ~w\n",
               [Enabled, SleepSet]),
      Backtrack =
          case Flavor of
              fake ->
                  case ordsets:is_element(Lid, Enabled) of
                      true when Preemptions =:= PreBound ->
                          [Lid];
                      _Else -> Enabled
                  end;
              _Other ->
                  case ordsets:subtract(Enabled, SleepSet) of
                      [] -> [];
                      [H|_] = Candidates ->
                          case ErrorNext of
                              none ->
                                  case ordsets:is_element(Lid, Candidates) of
  