mkosi (make operating system image) is a tool to generates OS images using package managers and repositories of many linux distributions. Let’s see how mkosi can help building System Extension Images.

Immutable OSes usually allows or even require declarative configuration: brief overview of the cloud-init, ignition, butane and combustion tools and formats

systemd-sysext activates/deactivates system extension images. […] (man systemd-sysext)