On Mon, Oct 02, 2017 at 10:00:33PM +0200, Ludovic Courtès wrote:
> Right.  Jan suggested checking the content-addressed mirrors *before*
> the real upstream address.  That would address the problem of upstream
> sources modified in-place, but at the cost of privacy/self-sufficiency
> as you note.  (Though it’s not really making “privacy” any worse in this
> case: it’s gnu.org vs. github.com.)

Yeah, I don't personally think there is a privacy issue with fetching
sources from our mirrors at gnu.org, or other domains we control.

> Perhaps we should make content-addressed mirrors configurable in a way
> that’s orthogonal to derivations, something similar in spirit to
> --substitute-urls?  The difficulty is that content-addressed mirrors are
> not just URLs; see (guix download).
>
> Thoughts?

I do think we should make it so that users don't suffer from unreliable
upstream sources when we know the sources are available on our servers
(or the Nix mirror), even with --no-substitutes.