[theptip]

Strongly agreed on these pain points. One tool I have been using recently to help is django-seal, which locks the QuerySet so you can’t run extra queries. This should really be part of the ORM, fail-unsafe is a bad option for performance critical code.

Combined with the Repository pattern from DDD, you can have all your model fetches go through a separate class that does the necessary select-/prefetch-related calls, then seals. (Or just override your model's Manager to do this).

And we have a coding standard guideline to discourage using queryset operators in business logic, as you note it breaks encapsulation and makes your code really hard to refactor later. This is hard to enforce though…

I think Django’s ORM is if anything too convenient - it’s great for the first 100kloc but then as you say, you need to overlay some discipline to prevent things from blowing up, and the framework is all about removing friction which makes this hard.