The project runs many Guix-specific services; this is all lovely Scheme code but it tends to receive less attention than Guix itself:
There is no time constraint on this coding activity: any improvement is welcome, whenever it comes. Most of these code bases are relatively small, which should make it easier to get started.
Prerequisites: Familiarity with Guile, HTTP, and databases.
If you wish to get started, check out the README of the project of your
choice and get in touch with guix-devel and the primary developer(s) of the
tool as per git shortlog -s | sort -k1 -n
.