Hi Felix & Efraim, Update on this. Does indeed seem to have been hardware related.
I managed to catch in one of the boots a bunch of `not a correct XFS inode' messages. I tried doing a live-usb boot and running xfs-repair tools on the partition, but this did not resolve it. I eventually just got a new drive and reinstalled Guix (on BTRFS this time) and boot times are normal again. (Misc. - the EFI ext4 partition was a red herring, as I for some reason had that partition but was using MBR/BIOS anyway. When I put in the new drive, I got into my BIOS settings and got UEFI turned on and set up the EFI partition properly as vfat &c.) best, —Benjamin -- '(Dr Benjamin Slade (he/him) (website . <https://lambda-y.net>) `(pgp_fp: ,(B20E 444C FA80 B5F8 15FA 4AD8 6FBF CD68 3B05 2B84)) "sent by [mu4e] 1.12.9 in [Emacs] 30.1 with [org-msg] on [GNU Guix] ([Linux])") [mu4e] <https://www.djcbsoftware.nl/code/mu/mu4e.html> [Emacs] <https://www.gnu.org/software/emacs/> [org-msg] <https://github.com/jeremy-compostella/org-msg> [GNU Guix] <https://guix.gnu.org/> [Linux] <https://opensource.com/resources/linux>