title: Request-reply broker in ZeroMQ using one worker with asynchronous tasks
body: <p>I want to implement a design similar to the <strong>Request-Reply Broker</strong> from the <a href="http://zguide.zeromq.org/page%3aall" rel="nofollow">ZeroMQ zguide</a> but instead of having multiple worker threads running ahead of time, I want to have one worker that receives all the requests, and spawns asynchronous operations (tasks) to handle them and send the responses.</p>
  
  <p>What would be the proper combination of socket types to achieve this?</p>