Have you looked at Apollo framework (for node) by any chance? I know it's not in your list of interests, but it might be worth checking out. Other than that, I

Have you looked at Apollo framework (for node) by any chance? I know it's not in your list of interests, but it might be worth checking out. Other than that, I have heard really nice things about Elixir/Phoenix. Everything is a stream so it does depart a bit from the others. Python, PHP and Ruby are all more traditional setups.