Also have a look at https://en.opensuse.org/Kubic:MicroOS https://en.opensuse.org/Kubic:MicroOS It uses btrfs instead of OSTree. It only allows writes inside /

Also have a look at https://en.opensuse.org/Kubic:MicroOS https://en.opensuse.org/Kubic:MicroOS It uses btrfs instead of OSTree. It only allows writes inside /home, /var, /tmp, /etc, ... and everything else is updated transactionally.