Ludovic Courtès transcribed 1.4K bytes:
> Hi Konrad,
> 
> Konrad Hinsen <konrad.hinsen@fastmail.net> skribis:
> 
> >> That error looks suspicious.  Perhaps you already know this, but it
> >> probably means that the string "mirror.hydra.gnu.org" wound up being
> >> used where a procedure should probably have been used instead.  For
> >> example, in your Guile REPL, you can reproduce this kind of error like
> >> this:
> >>
> >>     scheme@(guile-user)> ("this is not a procedure")
> >>     ERROR: ERROR: Wrong type to apply: "this is not a procedure"
> >
> > Suspicious indeed...
> 
> It turned out to come from a typo in Guile 2.2’s web client, now fixed
> here:
> 
>   https://git.savannah.gnu.org/cgit/guile.git/commit/?h=stable-2.2&id=7d0d9e2c25c1e872cfc7d14ab5139915f1813d56
> 
> and I’ve done some monkey-patching here:
> 
>   https://git.savannah.gnu.org/cgit/guix.git/commit/?id=59da6f04f45b36696a9385babab3080d7d854fba
> 
> I’ll update the ‘guix’ package soon so that this change is available to
> daemon-side code such as ‘guix substitute’.  In the meantime you can run
> the daemon from a checkout:
> 
>   sudo -E ./pre-inst-env guix-daemon …
> 
> For reference, I used this command to test proxy support:
> 
>   http_proxy=http://localhost:8118 \
>   ./pre-inst-env guix download http://www.gnu.org
> 
> where Privoxy is listening to localhost:8118.
> 
> Thanks for reporting the issue!
> 
> Ludo’.

Oh. I think I encountered a similar (or the same?) problem one
year ago without ever reporting it.
I'll check soon if my usecase is fixed with your latest commits.

Thanks for working on this!
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