I see Chris Holland mentioned it about a year ago, but one other you may want to consider is
- popular for Go development.
NATS Server is written in Golang, is very lightweight and simple to use, as well as extremely fast. Some of you may have seen the GopherAcademy post on it in December:
https://blog.gopheracademy.com/advent-2015/nats-high-performance-cloud-native-messaging-written-in-go/
For those of you headed to GopherCon, there is a workshop on HackDay as well on NATS:
http://bit.ly/1XpeSq6
Since Chris mentioned it, NATS has become even faster and functionality has continually been updated - have a look. Regardless of whether you use NATS or not, be interested in your input on the project so just ask if any questions, comments, etc.
B