People are replying that NATS isn't the same as ZeroMQ. But, I think the missing piece here is that most people who are looking at ZeroMQ really just want something like NATS. There is a decent amount of effort required to make ZeroMQ work. Whereas, NATS just does the thing you wanted in the first place without all that effort.
They're not even remotely the same thing. You could build NATS on ZeroMQ but not the other way around. ZeroMQ is more like a network/message-passing abstraction library while NATS is a service.
I'd 90% agree with this, except that NATS does have an embedded mode.[0] That plus the clustering, gateway, and leaf-node features gets it very close to what ZeroMQ is doing, though at a much higher complexity level that's maybe unnecessary depending on what you're doing. Embedding is exclusive to Go programs, so that's very limited compared to ZeroMQ.
Even in embedded mode NATS is doing way more than ZeroMQ is, it's a full-blown message queue system while ZeroMQ at best gives you the tools to build a message queue.
