anchor.diff:  
   to_stderr(Format, Data) ->
     io:format(standard_error, Format ++ "~n", Data).
  +
  +parallelism() ->
  +  erlang:system_info(schedulers).
  
positive.code:   Server ! {test, File, Test, Status}.
  
  run_and_get_exit_status(Command) ->
    Port = open_port({spawn, Command}, [stream, in, eof, hide, exit_status]),
    get_exit(Port, infinity).
  
  get_exit(Port, Timeout) ->
  
negative.code:    , failed = 0
     , files  = 0
     , finish = false
     , limit  = parallelism()
     , tests  = 0
     }).
  
  initialize() ->
    After17 =
      case erlang:system_info(otp_release) of
        "R" ++ _ -> false; %% ... 16 or earlier
        [D,U|_] -> list_to_integer([D,U]) > 17
      end,
    case After17 of
      false ->
        to_stderr("Skipping because OTP version < 18", []),
        halt(0);
      true ->
        print_header(),
        spawn_link(fun() -> loop(#state{}) end)
    end.
  
  loop(#state{done = All, finish = {true, Report}, tests = All} = State) ->
    #state{failed = Failed, files = Files, tests = Tests} = State,
  