anchor.diff:                  NumberVMs = get_number_of_vms(),
                   io:format("Executing: ~p~n", [Cmd]),
                   _ = os:cmd(Cmd),
  -                wait_for(fun get_number_of_vms/0, NumberVMs - 1)
  +                util:wait_for(fun() -> get_number_of_vms() =:= NumberVMs - 1 end)
           end,
       _ = [RemoveFun(NodeName) || NodeName <- lists:sublist(VMs, N),
                                   get_number_of_vms() > config:read(cloud_local_min_vms)],
  
positive.code: %%%%%%%%%%%%%%%%%%%
  %%%% Helper methods
  %%%%%%%%%%%%%%%%%%%
  wait_for(Fun, ExpectedValue) ->
      case Fun() of
          ExpectedValue -> ok;
          _ ->
              wait_for(Fun, ExpectedValue)
      end.
  
  -spec find_free_port(comm_server:tcp_port() | [comm_server:tcp_port()] |
                           {From::comm_server:tcp_port(), To::comm_server:tcp_port()})
          -> comm_server:tcp_port().
  
negative.code:                  io:format("Executing: ~p~n", [Cmd]),
                   NumberVMs = get_number_of_vms(),
                   _ = os:cmd(Cmd),
                   util:wait_for(fun() -> get_number_of_vms() =:= NumberVMs + 1 end),
                   timer:sleep(200)
          end,
      _ = [SpawnFun(X) || X <- lists:seq(1, N), get_number_of_vms() < config:read(cloud_local_max_vms)],
  