On Thu, Oct 05, 2023 at 05:03:49PM +0200, Emmanuel Beffara wrote:
> Hello Guix,
> 
> Is there a way to share Guix and its store between several distributions?
> 
> My situation is that I have a Guix system installed as my main system, but I
> would like to install another distribution on the same machine (a current
> Debian, specifically) and use Guix as a package manager there, in order to
> benefit from its ability to create reproducible environments. 
> 
> Of course, it works to have the other distribution completely independent,
> with its own Guix store. The only thing is to handle Grub correctly to give
> access to both distros. But it feels like a significant waste of resources,
> since I will end up having many things in both stores.
> 
> Moreover, ideally I would like to share home directories between the two
> distributions, by mounting the same partition as /home, and still be able to
> use `guix home` and `guix shell` in both distributions. By some minimal
> tuning, I can make it so that users have the same UIDs and GIDs in both
> distributions. But I imagine that using Guix in both distributions can become
> problematic if they don't share the store and the state in `/var/guix`, for
> instance if they don't share GC roots.
> 
> Is there a proper way to make that work? Or is it a bad idea?

It looks like you already have the right idea. You'd have to share /gnu
and /var/guix between the two distributions, as well as have the same
UID (and possibly GID) for the users. You would also have to tell Guix's
grub to also add an entry for Debian.

I don't know if you'd end up having issues with graphical programs from
Guix overriding environment variables for Debian or if there might be
issues with guix-home with a foreign distro.

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Efraim Flashner   <efraim@flashner.co.il>   רנשלפ םירפא
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