So is MQTT, why bother with NATS then?

MQTT doesn't have the same semantics. https://docs.nats.io/nats-concepts/core-nats/reqreply request reply is really useful if you need low latency, but reasonably efficient queuing. (making sure to mark your workers as busy when processing otherwise you get latency spikes. )

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RedShift1 3 hours ago | parent [-]

You can do request/reply with MQTT too, you just have to implement more bits yourself, whilst NATS has a nice API that abstracts that away for you.

	▲	KaiserPro 3 hours ago \| parent [-]
		oh indeed, and clusters nicely.