Here’s the concrete sysext plan I’d use.
Goal
Build an incus.raw system extension that overlays only /usr, while keeping Incus state on the host in /var/lib/incus, /var/cache/incus, /var/log/incus, and /run/incus.
1. Define The Artifact
Create a separate dakota-incus-sysext build artifact, initially out-of-tree.
The sysext should contain: