nix CI

[bgregoir]

With Cyril help's

[eponier]

We discussed with @CohenCyril about how to use coq-nix-toolbox to both have nix-shell and ci. This PR is a proof of concept.

@CohenCyril explained that by default there is no caching. If we want some, we would have to ask for an access for Coq's cache or create our own account elpi/coq-elpi on Cachix. We can also disable the test of reverse dependencies if we find it too costly.

[CohenCyril]

@Zimmi48 could we make room for a LPCIC cache in the coq cachix organization?

[eponier]

@gares To be fair w.r.t. Cyril's work, the effort was pretty small. It was basically a matter of following https://github.com/coq-community/coq-nix-toolbox#standalone. With Cyril's help, it was straightforward. But it may become more complex for more advanced stuff, I don't know.

[gares]

Fine with nix, but please don't remove the other workflows. One builds the doc, which I don't think nix does.
The other is probably subsumed by nix.

[gares]

I did the fix myself, if it works I'll merge

[Zimmi48]

Sure, we can add @gares to the "Coq ecosystem" Cachix organization. Please contact me by private message on Zulip.

[gares]

@CohenCyril why don't you become an admin of this repo and set up cachix?

[CohenCyril]

@CohenCyril why don't you become an admin of this repo and set up cachix?

Sure admin me

[gares]

Apparently there is a "maintainer" role, but I could not understand if you can create secrets (it seems so, but the doc is not clear to me). Please try, if not I'll admin you.

[CohenCyril]

@gares I do not have access to secrets as of now.

[gares]

ok, now you are Admin.

[CohenCyril]

@gares to reactivate rev dep test on HB for example
cf #334

[CohenCyril]

@gares

Suggested change

	#coqPackages.hierarchy-builder.job = false;
	coqPackages.hierarchy-builder.override.version = "master";