core

Fields in Drupal 9 can be defined in code, or they can be defined in configuration. Both techniques have their uses and advantages. Typically code fields apply to all bundles of the entity type, as so-called base fields, while config fields apply only to a single bundle.

But there is a way to have code fields which apply only to specific bundles: these are called bundle fields. These are particularly useful for adding computed fields to specific bundles of an entity (more on computed fields in a future blog post).

I've been mulling this idea since Paris, trying to figure out the best way to present it.

But basically:

We want a smaller, slimmer, efficient core.
But we also want Drupal to, like, be useful.
We want contrib, at least the high-use end of contrib, to be smoother, more organized, released on time with core.
It's been suggested we have a contrib maintainer, who would have the unenviable task of managing a huge kaboodle.