I am interested in setting up my installation of Guix with root-on-tmpfs-style
"impermanence," so I was happy to see that these patches were merged.
Unfortunately, I cannot seem to make it work. My approach was to use a main
partition mounted at `/persistent` with directories underneath like
`/persistent/var/{log,lib,guix}` that were bind-mounted on top of the tmpfs at

Not mentioned as far as I can see in this thread is what about `/gnu/store`.
Should that also be stored persistently or does it originate from inside
`/var/guix`? Originally I tried having `/gnu` be the persistent filesystem with
subdirectories `/gnu/persistent/var/...` and `/gnu/store`, but this interfered
with the `%immutable-store bind mount`.

Would you be so kind as to share a working configuration snippet using
root-on-tmpfs? (I understand if you're using btrfs subvolumes; it would still be
useful to me I think to see the configuration.)