> Also, don’t you run into scenarios in Django where the automatic migration is not enough and you need to provide custom commands? In such cases, how do you provide them?

Data migrations are the obvious case where you need to write migration code manually. It comes up in schema migrations too on big projects. It’s easy to modify the auto-generated migration; it’s just Python that gets run by the migration tool:

https://docs.djangoproject.com/en/4.1/topics/migrations/#dat...