Pierre Neidhardt <mail@ambrevar.xyz> writes:

> Hi Chris!
>
> Christopher Baines <mail@cbaines.net> writes:
>
>> My current workflow is, look for patches to review through email, or
>> Patchwork [1], look the patches over, follow the link to the Guix Data
>> Service instance,
>
> Which link?

If you go to a patch, like: https://patchwork.cbaines.net/patch/20613/
there are some links in the Checks section. The "View comparison" link
takes you to a Guix Data Service instance, the "View Git branch" link
takes you go a Git repository containing the patches, and the "View
Laminar job" link takes you to the job in Laminar that tried to apply
the patches.

>> and maybe try building some of the derivations [2]. If
>> I want to manipulate the patches locally, I checkout the branch or
>> cherry-pick the relevant commits [3].
>>
>> 1: https://patchwork.cbaines.net/project/guix-patches/list/
>> 2: I use the substitutes from the Guix Data Service instance for the
>> derivation, so I can build it locally without having to apply the
>> patches.
>
> Is there a public substitute server from the Guix Data Service?

I realise that it's not easy enough to find this out, but the Guix Data
Service provides substitutes for the derivations it knows about. It
stores all the information about derivations, and it also stores the
sources referenced by the derivations.

This means it can provide substitutes for these store items. Take mxnet,
if you trust the key (which can be found here
https://guix-patches-data.cbaines.net/substitutes ), then you'll be able
to do:

  guix build --substitute-urls="https://guix-patches-data.cbaines.net" /gnu/store/9xcmc4z6w0brg17l1frz6blg79wgf7yi-mxnet-1.6.0.drv

As I understand it, Guix will download the derivation graph from the
Guix Data Service until it has the derivation locally, then it will
build it as normal.

Hope that makes sense?

Chris