It appears that:

  b97b423e3f61c80d5877dadc95b3f316cd61788f bootloader: Fix u-boot
  installation.

Breaks using a /dev/disk/by-id/ symlink in the bootloader target field
on systems using u-boot with "guix system reconfigure".

Frustratingly, It claims to succeed with bootloader installation, but
does not actually install u-boot to the device... when updating to the
new version of u-boot, I had to manually install the new version.


Using a raw device (e.g. /dev/mmcblk1) still works, but those devices
are not necessarily enumerated in a consistent order and so cannot be
used in a config.scm with guix system reliably.


Reverting that patch fixes using the /dev/disk symlink, though probably
breaks other use-cases.


I'm writing this from memory now, but I can also boot the machines at a
later point and get the exact configurations, if needed.


live well,
  vagrant