Hi,

It appears guix-daemon.service leaks some replacement variables defined in
guix-daemon.service.in, e.g.:
--8<---------------cut here---------------start------------->8---
Environment='GUIX_STATE_DIRECTORY=/var/guix' 'GUIX_LOCPATH=@localstatedir@/guix/profiles/per-user/root/guix-profile/lib/locale' LC_ALL=en_US.utf8

# Run under a dedicated unprivileged user account.
User=guix-daemon

# Bind-mount the store read-write in a private namespace, to counter the
# effect of 'gnu-store.mount'.
PrivateMounts=true
BindPaths=@storedir@
--8<---------------cut here---------------end--------------->8---

From what I can tell, the replacement is done by nix/local.mk (not self.scm).
The sed script there doesn't include all variables, nor is it replacing
matched patterns globally.

Thanks,
Ido.