The underlying technology (read-only btrfs system snapshots) is actually much older than CoreOS (in SLE it was introduced somewhere in SLE 11 IIRC) and the idea

The underlying technology (read-only btrfs system snapshots) is actually much older than CoreOS (in SLE it was introduced somewhere in SLE 11 IIRC) and the idea to use it in a similar way as this is almost as old. It has multiple advantages over rpm-ostree's approach: - Much faster (no need to manage thousands of hardlinks) - Arbitrary modifications can be done easily in a chroot - Not only /usr is snapshotted - No need for layering and rebases (rpm-ostree has a base image + rpms on top, which this doesn't need) - RPMs just work as-is, there are no hacks with %post scripts and so on