Well, Nix was mentioned a few posts up... But in general, Guix is directly based off of Nix and is seen by many as "Nix + Guile + GNU". Is it odd to see people talking about a different BSD in a {Free,Open,Net,*}BSD thread?
Guix is quite different from it's origins, though some of the oldest part of the daemon are still from the Nix days, if I understand. It will one day be rewritten in all Guile, presumably.