Implement power management (suspend, hibernate, resume) in Shepherd?

[Mekeor Melire]

I'm bumping this old thread:

    https://lists.gnu.org/archive/html/guix-devel/2015-03/msg00757.html

because I'd like to discuss if it still makes sense to implement power
management, i.e. suspend (to memory=RAM), hibernate (to (hard) disk) and
resume in GNU Shepherd. As far as I can see, Shepherd currently only
provides ‘halt’ and ‘reboot’.

As far as I understand, currently GuixSD uses elogind (“systemd
project's ‘logind’, extracted to a standalone package”) to suspend,
hibernate and resume when some events happen, like pressing the
suspend-key etc.

Is there any nice way to suspend GuixSD by command? (I didn't yet try
out ‘echo mem > /sys/power/state’.) Is it still desirable that Shepherd
itself could get this job done?