The "MQ" part of the name is unfortunate, but apparently came about because of the original idea to come up with a "better" implementation of AMQP (http://zerom

The "MQ" part of the name is unfortunate, but apparently came about because of the original idea to come up with a "better" implementation of AMQP (http://zeromq.org/docs:welcome-from-amqp http://zeromq.org/docs:welcome-from-amqp). But you're right -- ZeroMQ doesn't do queueing (except in some very limited circumstances), and if you need reliable delivery you must implement that yourself "on top of" ZeroMQ. I've done that, and while it's not a simple task, it is certainly possible. You can get reliable delivery "out of the box" with other software, that in fact does do queueing. (kafka may be one, but I don't know enough to say). But what you give up when you do that is performance -- ZeroMQ can easily be orders of magnitude faster than those other solutions, and for some applications (e.g., real-time market data) the work to provide a custom reliability solution on top of ZeroMQ is worthwhile.