bug#22629: “Stable” branch

[Ludovic Courtès]

Hi Alex,

(Cc’ing <https://bugs.gnu.org/32022> and <https://bugs.gnu.org/26608>,
which are related.)

Alex Sassmannshausen <address@hidden> skribis:

> I don't know if this is what Konrad desires, but from my perspective, a
> desirable part of the definition of stable would be a that the build
> farms have produced a set of binaries/substitutes for a given Guix
> revision that is "good enough".

I just had a bright idea (yes!): this can be addressed by writing
something like this in ~/.config/guix/channels.scm:

  (map latest-commit-with-substitutes-available
       %default-channels)

The hypothetical ‘latest-commit-with-substitutes-available’ would use
(git) and (guix ci) to find the latest commit for which substitutes of
interest are available, and would return:

  (channel
    ;; …
    (commit "cabbag3"))   ;the ideal commit

This has to be done with great care to prevent a downgrade attack and to
make sure the user doesn’t miss out on security updates, but maybe we
could provide a procedure that makes reasonable choices.

Food for thought…

Ludo’.