Being able to extend and customize the editorial experience for users has been a part of any WordPress developer’s toolbox since hooks were introduced in WordPress 1.2. With the Gutenberg Project, developers have a new tool available: SlotFill.

The SlotFIll system can extend blocks and the UI for the Block Editor and Site Editor screens. This talk is a deep dive into how this system works. Learn how and where you can extend WordPress and how to create your own custom SlotFills.