Hi,

auctex is not compatible use-package / elpa handling.  As a use-package
user, after installing auctex from Debian, it will try to install auctex
from elpa.gnu.org nonetheless.  This is because the current auctex
layout doesn't follow elpa convention so that it cannot be detected by
use-package.  It would be great to make it compatible so that
use-package users don't have to install auctex twice.

I have attempted to convert auctex to use dh-elpa and prepared a MR[1],
please review.  Thanks in advance for considering!

[1] https://salsa.debian.org/salve/auctex/-/merge_requests/3

I have made a new MR[1] using a separate branch so that I can continue
to experiment on master.  It also changes how *-pkg.el is generated.
PTAL.

I encountered the same exact problem on Emacs 30.1 (the version packaged
in Trixie).  It would be great to see this solved, so that the Emacs
version in stable can "transparently" avoid depending on GNU ELPA when
the Debian auctex package is installed.