Within your public/index.php you will need to upgrade
$cubex = new Cubex(dirname(__DIR__), $loader);
$cubex->handle(new Application());
to
use Cubex\Workerman\CubexWorker;
$worker = CubexWorker::create(
dirname(__DIR__),
$loader,
function () { return new Application(); },
'http://0.0.0.0:3000'
)->setCount(4);
this will run workerman on port 3000 with 4 processes