Your business logic should not be tied your persistence, that's what I mean by it.

By "domain objects" I don't mean that you need to embrace OOP, they could be simple structs without any associated logic.

> PPS - N+1 queries are kinda trivial to resolve in most cases in Rails? There's core ORM functionality for it.

The problem isn't that you can't fix N+1 queries in Rails, it's that it's incredibly easy to create them by accident because your ActiveRecord objects carry a DB connection around everywhere, even in views.