I think I get the idea of Fedora Atomic (Silverblue, Kionite, etc.), but I do not get what uBlue is about.
Are those just another “ooh it’s distro X but with preinstalled Y” or are those some soft of overlays on top of Fedora? Can’t they just be some install scripts? Why not just base Fedora Silverblue? Maybe I don’t get the idea, because people seem hyped.
Starting to write about this, it is actually really complex as rpm-ostree is really powerful. Read the man entry, it tells a lot.
Ostree can use ostree remotes (like git repos) or “ostree native containers” i.e. OCI containers (like Docker, Podman etc. which uBlue uses.
the rpm part meanwhile allows to add any RPM to the image, but it takes way longer. So doing this centrally is more efficient.
This has tons of benefits like adding packages that Fedora cannot legally add, or doing opinionated changes, or unstable stuff like drivers.
Instead of having every user apply them, this does them once and by that increases reproducibility.