I keep vacillating between "Guix rules, actually" and "what the fuck is this nonsense."
I'm in the latter place today, as I found that an important part of the Scheme code doesn't work unless the path to the process it's running in ends in "bin/guix". This means that when you use Emacs and Geiser to run Guile to hack on Guix packages, it can't use any packages from any channel other than the default one.