I've switched to it yesterday and since then it seems I have to compile
everything myself :(
Subversion, git, boost, to name a few.

I do get the source from qualif.ci.guix.gnu.org though:

--8<---------------cut here---------------start------------->8---
downloading from https://qualif.ci.guix.gnu.org/nar/z4yv0m8wqfqgpgqalgx1dlqylq6rwqyg-git-2.21.0.tar.xz...
--8<---------------cut here---------------end--------------->8---

Is this expected?  If not, any idea how to investigate?

-- 
Pierre Neidhardt
https://ambrevar.xyz/