Am Samstag, 12. Januar 2013 schrieb Ludovic Courtès:
> Any other ideas?  Comments?

One thing that could be improved: Right now, I still need to start the 
daemon with
   guix-daemon --build-users-group=nixbld
Since this is the recommended setup (at least from the nix manual, I did 
not check if the guix manual gives details), would it be possible to change 
the daemon code in the following way:
If --build-users-group is not given explicitly, check for the group nixbld 
and use it if it exists.

Andreas