NSQ is a message broker that's intended to run in a distributed fashion, i.e. one broker per machine which is producing messages. Consumers then have to discover and connect to all brokers that carry messages on a given topic. NSQ persists messages to disk, but it does not have replication, so if one of the machines with the brokers dies (as in dead disk), all queued messages will be lost.

We use NSQ extensively and its a great fit for us. It's fast, lightweight, very easy to understand and work with, has great HTTP APIs for controlling the queues and publishing messages, etc. What it doesn't have is replication, so if a message must not be lost ever I'd reach for a distributed log, probably looking at Redpanda before Kafka, and possibly building my own on top of ScyllaDB since we're already running that.

I haven’t used it so I’m not qualified to answer, sorry. I can only tell why I never used it: as far as I understand it’s possible to have data loss with nsq and there’s no replication.