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 # Silverblue-ZFS
 
 This is a customized Universal Blue image with the OpenZFS kernel module installed.
+
+See [upstream Universal Blue](https://github.com/ublue-os/main/) repo for more detailed instructions how
+to rebase to this image.
+
+The ZFS modules are built against the latest latest ublue-os:main image, Fedora 40 at the time of writing.
+Building the modules is basically taken straight from [Fedora CoreOS](https://github.com/coreos/layering-examples/tree/main/build-zfs-module)
+example, except the base image used to detect the correct version is `ublue-os:main`.
+
+## Known issues
+The build fails consistently once a week. Most likely Fedora repos are already serving a newer kernel version,
+while the pulled ublue image is still on the older kernel version. Next day's build succeeds, so this only means
+a day without an updated image every week.
+
+Dependencies for Jim Salter's excellent [Sanoid/Syncoid](https://github.com/jimsalterjrs/sanoid) might become
+preinstalled at some stage, but for now I've decided to keep everything close to `ublue-os:main`. Suggestions,
+issues and pull requests are welcome.