Do not report issues to the upstream when running this to update your system.
Read the Nix expression, understand it, run the script, knowing that this is unsupported by either the author of the expression, or the author of the firmware.
Run the output as root.
Whenever I notice them and get around to it. Contributions welcome.
Seriously do not report issues to the upstream when running this to update your system.
This may render your system unbootable. Good luck.