Writing custom Laravel queue driver

I'm in the process of writing a custom Laravel 5.5 queue driver for interacting with MQTT. I'm using the Mosquitto MQTT extension.

There's not a lot of documentation on how to implement this. What has me stuck is understanding the expected payload. When my pop() method is being called, and my MqttJob class is being processed, I receive an error about a missing index 'job'. I've tried looking at the implentation of various other drivers including Redis, Beanstalkd, and other custom drivers like for Kafka, and RabbitMQ, but still see where their implementations follow this expected payload structure.

If anyone has experience or understanding of how the queues, workers and jobs interact, it'd be much appreciated.

via Chebli Mohamed