[Bio-packaging] Using a shared Guix store (was RE: testing out guix)

[Ricardo Wurmus]

Cook, Malcolm <MEC at stowers.org> writes:

> Also, you discussed need for setting NIX_STATE_DIR.  This should not
> be needed if guix was already installed with configuration of
> --localstatedir=/guix/var (with /guix being nfs mounted), right?

NIX_STATE_DIR is used to override localstate at runtime.  If you are
happy with the localstatedir (defined at configure time) you do not need
NIX_STATE_DIR.  After my vacation I’ll take some time to think about how
to allow users to run “guix” on cluster nodes to manipulate their
profiles — and how to reliably set this all up.  I’m planning on
documenting this, both in a specialised form for my blog and in a more
generic fashion for the Guix manual.

> Ricardo also wrote "For ‘guix package’ to work,
> /gnu/var/guix/profiles/per-user must be shared read-write (over NFS)
> with correct UID mapping." - I really don't understand this and tried
> to elicit feedback in
> http://lists.nongnu.org/archive/html/guix-devel/2015-07/msg00216.html
> - Can anyone give me clarification on this.  I though the guix daemon
> is going to manage these profiles.

I don’t remember writing this or the context in which I wrote this
(could it be that Ludovic wrote this?) — looking at the code for
guix/scripts/package.scm it seems that the client performs some of the
symlink switching when switching generations (e.g. after installing a
new package).  For that to work it would need write permission to the
user’s profile directory.

(I could be completely wrong here.  That’s not how it’s set up here and
I haven’t yet tested a configuration like this.)

~~ Ricardo