Thanks a ton for Phoenix :D Re the clustering support, I can see in your article here https://dockyard.com/blog/2016/01/28/running-elixir-and-phoe... that the Erlang VM joins clusters on startup - any idea if it's easy or possible to dynamically join and leave clusters?

Sort of what you'd expect in a cloud environment: one or two bastion servers would have a known IP address, and the remaining would be expected to learn about the cluster when the joined with the bastions.