Lately I’ve been exploring FreeBSD and OpenBSD. One of the more interesting things about them is how they handle OS and package upgrades.
On FreeBSD, the freebsd-update command is used for upgrading the OS and the pkg command is used for managing user packages. On OpenBSD, the syspatch command is used for upgrading the OS and the pkg_* commands are used for managing user packages.
Unlike Linux, these BSDs have a clear separation of OS from these packages. OS files and data are stored in places like /bin and /etc, while user installed packages get installed to /usr/local/bin and /usr/local/etc.
On the Linux side, the closest thing I can think of is using an atomic distro and flatpak, homebrew, containers, and/or snap for user package management. However, it’s not always viable to use these formats. Flatpak, snap, and containers have sandbox issues that prevent certain functionality; homebrew is not sandboxed but on Linux its limited to CLI programs.
There’s work being done to work around such issues, such as systemd sysext. But I’m starting to feel that this is just increasing complexity rather than addressing root problems. I feel like taking inspiration from the BSDs could be beneficial.
Gentoo will allow you to update the small set of required system packages and their dependencies separately from everything else (
emerge --update system), but doing the reverse would require some pretty heavy micro-management.