Sure; though, as I mentioned before I did try again and it did work. Doing
a pull once more I failed with:

guix substitute: error: TLS error in procedure 'handshake': Error in the
pull function.
substitution of
/gnu/store/k1da7bv579d8gvwdrakd9l4hxswknff2-guix-module-union failed
guix pull: error: some substitutes for the outputs of derivation
`/gnu/store/k2gdq7ahjaqmdgjr9xwywqpxvzazn467-guix-e07573432.drv' failed
(usually happens due to networking issues); try `--fallback' to build
derivation from source

As with before, I was also able to succeed on a subsequent pull; but this
error seemed to be handled better as it suggested both the cause of the
problem and a possible solution.

On Mon, Jun 15, 2020 at 12:42 PM Ludovic Courtès <ludo@gnu.org> wrote:

> Hi,
>
> Quinten Gruenthal <quintengruenthal@gmail.com> skribis:
>
> > |substitute: guix substitute: error: TLS error in procedure 'handshake':
> > Error in the pull function.
>
> [...]
>
> > I've seen this kind of error before in other software and I believe it
> > occurs when a handshake can't be performed in time and the connection is
> > dropped; I was able to successfully pull a few minutes later under better
> > conditions. That being said I bring this up because a problem in my
> network
> > (I think) is being treated like an error in your program.
>
> Yes, it looks like a connectivity issue, either on your side or on the
> side of https://ci.guix.gnu.org (though I’m unaware of downtime today).
>
> Could you try again?
>
> Thanks,
> Ludo’.
>