SeerLite via Bug reports for GNU Guix schreef op do 14-04-2022 om 12:45
[-0400]:
> However, now I can't run `guix upgrade`. I get the following error:
> 
>      guix upgrade: error: the source of kakoune@2021.08.28 is not a Git 
> reference

I guess the problem is that 'with-branch'/'with-commit' come before
'with-git-url' in
<https://git.savannah.gnu.org/cgit/guix.git/tree/guix/transformations.scm?id=237d90a7808cfdced34b34595eba16632cbcb89e#n794>
(untested!).

Greetings,
Maxime.