Not trying to be a nit-pick, but wanted to mention that ZeroMQ is not a message queue in the sense that RabbitMQ (and Kestrel, Beanstalkd, SQS, etc) is. It's a socket library that you'd use to implement those technologies.

And while this is truly unimportant, my experience with bay area startup stacks is that Redis has very thoroughly supplanted Memcached for most use cases. Though most still have a memcached cluster or two.

That being said: 90% of software development in this world isn't done at tech companies and startups. So from that perspective, that stack is interesting.