Hi! Danny Milosavljevic skribis: > I think it's a good interim solution. Based on your feedback I’ve come up with the two attached patches. I’ve checked at the REPL that ‘operating-system-uuid’ gives reasonable results for different ‘operating-system’ configs, and deterministic results for a given config (OSes that are not ‘eq?’ but that are equal.) On ext4 “guix system disk-image” produces an image that works like a charm. With iso9660, it works… by chance, because GRUB’s “search --fs-uuid” fails. Guess why? Because it compares UUIDs as strings, and we format it as a DCE UUID instead of an ISO UUID. Sounds familiar no? :-) So that’s where we are. Thoughts on how to address it? Cheers, Ludo’.