TEN7: Adding Bundle Subclasses to Drupal Core 9.3.0 (Part 3)

In Part 1 of this blog series, we explored the concepts of entities, bundles, entity classes, and the new feature of bundle subclasses now available in Drupal Core 9.3.x. In Part 2, we looked at some specific code samples to see some of the ways to use this feature to make your life better. Now we turn to the story of what it took to get this feature included in Drupal Core: using a Gitlab merge request (MR) instead of patches, what it takes to get something like this committed, how and why to contribute “upstream,” and more.