PlutoOS
pluto is a very opinionated immutable linux distro that is (at the moment) very optimized for framework laptops specifically. everything possible is systemd based (i told you it was opinionated), systemd-boot, run0, etc. it uses a/b partitioning and rauc bundling to distribute root filesystems with overlay fs's when needed. kde plasma desktop, a background monitor to keep everything running as smooth as possible, battery optimizations, and a heavy emphasis on flatpaks
not much to see on this site right now, as it's primarily used as an endpoint for the OS and nothing else.