The path to erl is embedded differently in /usr/bin/manderlbot depending
on if it was built on a usrmerge vs. non-usrmerge system:

https://tests.reproducible-builds.org/debian/rb-pkg/bookworm/amd64/diffoscope-results/manderlbot.html

  ERL=/usr/bin/erl
  vs.
  ERL=/bin/erl

The attached patch fixes this by passing the path to ERL in a
debian/rules dh_auto_configure override. The path in /usr/bin is
compatible with both usrmerge and non-usrmerge systems.

According to my local tests, with this patch applied manderlbot should
build reproducibly on tests.reproducible-builds.org once it migrates to
testing! Unfortunately, there are other issues with build paths which
are only tested in unstable and experimental.

Thanks for maintaining manderlbot!

live well,
  vagrant

We believe that the bug you reported is fixed in the latest version of
manderlbot, which is due to be installed in the Debian FTP archive.

A summary of the changes between this version and the previous one is
attached.

Thank you for reporting the bug, which will now be closed.  If you
have further comments please address them to 1037296@bugs.debian.org,
and the maintainer will reopen the bug report if appropriate.

Debian distribution maintenance software
pp.
Sergei Golovan <sgolovan@debian.org> (supplier of updated manderlbot package)

(This message was generated automatically at their request; if you
believe that there is a problem with it please contact the archive
administrators by mailing ftpmaster@ftp-master.debian.org)
Format: 1.8
Date: Mon, 10 Jul 2023 09:18:50 +0300
Source: manderlbot
Architecture: source
Version: 0.9.3-2
Distribution: unstable
Urgency: medium
Maintainer: Debian Erlang Packagers <pkg-erlang-devel@lists.alioth.debian.org>
Changed-By: Sergei Golovan <sgolovan@debian.org>
Closes: 1037296
Changes:
 manderlbot (0.9.3-2) unstable; urgency=medium
 .
   * Incorporate the NMU by Holger Levsen.
   * Fix the debian/watch uscan control file.
   * Add patch by Vagrant Cascadian which fixes erl path for usrmerge systems
     (closes: #1037296).
   * Bump debhelper compatibility level to 13.
   * Bump standards version to 4.6.2.
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