I've seen organizations have lots of trouble operationally with kafka (which samza uses). I've seen NSQ be extremely reliable operationally. However they offer

I've seen organizations have lots of trouble operationally with kafka (which samza uses). I've seen NSQ be extremely reliable operationally. However they offer very different guarantees so it's an apples to oranges comparison. NSQ isn't really designed to provide a replayable history, although you can fake it by registering a consumer which does nothing but log to file (nsq_to_file) and that works pretty well. (disclaimer: the nsq mailing list has lots of chatter these days, nsq may be growing features I'm not aware of)