[previous e-mail was bogus. ggrr emacs, why can't I open e-mail
I was composing and saved with C-x C-f and continue later,
even if I set mml-mode]

Hi Guix,

If I didn't miss anything, this patch allows for booting with a non-standard
shepherd package, which may be useful for using features from a not-yet
released shepherd (presuming you've packaged the custom shepherd first :)).

I'll send a follow-up e-mail to confirm/disconfirm whether this works
well.

Maxime