Bootable containers on the Raspberry Pi

The question on how to use bootable containers on the Raspberry Pi (or other single board computers that have &lsquo;interesting&rsquo; boot setups) comes up quite regularly. For a while now it has been possible in image-builder to create a Raspberry Pi compatible partition table. I don&rsquo;t think this has been written down in long-form anywhere except answers to GitHub issues and Matrix chats.…