[red-iron-pine]

> MQTT is being used a lot more in recent years inside of factories for sharing data between machines. Historically it's been used in Oil & Gas for SCADA (getting data from remote well sites).

This is where I first encountered it too -- chemical production. Also saw a lot of it in aviation and railroad control systems.

That said, seeing a lot more Kafka and RabbitMQ crowding into MQTT's marketspace.