protected function listen()
    {
        $this->eventEmitter->on('peridot.concurrency.load', [$this, 'setPending']);
        $this->eventEmitter->on('peridot.concurrency.worker.run', [$this, 'addRunning']);
        $this->eventEmitter->on('peridot.concurrency.worker.completed', [$this, 'onWorkerComplete']);
        $this->broker->on('end', [$this, 'onMessageEnd']);
        $this->broker->on('error', [$this, 'onError']);
        $this->broker->on('suite.halt', [$this, 'stop']);
    }