> I've been writing runtime validations for each individual query result. This has been a bit annoying to maintain at scale since I don't have very good patterns for it.

I think pydantic [0] solves this problem perfectly. The objects you create with pydantic work with type systems such as mypy too, so you get all the editor support for them, if you want.

https://github.com/samuelcolvin/pydantic/