Asynchronous Database Access in Ruby

There's a strong urge to come up with a Rails stack that's end-to-end async, that looks and tastes like Rails but automagically performs 10x faster.

I'm not saying that's irrational, but it's not necessarily the best way to meet speed targets. Database queries are not immune to the 80/20 rule. You find the queries that are killing you, you factor them into handlers that run straight SQL async handlers, and you keep standard ActiveRecord for the vast majority of your code that isn't performance sensitive.