Diff of the two buildlogs:

--
--- b1/build.log	2024-04-30 17:53:32.411293053 +0000
+++ b2/build.log	2024-04-30 17:55:10.783114856 +0000
@@ -1,6 +1,6 @@
 I: pbuilder: network access will be disabled during build
-I: Current time: Mon Jun  2 12:13:57 -12 2025
-I: pbuilder-time-stamp: 1748909637
+I: Current time: Wed May  1 07:53:35 +14 2024
+I: pbuilder-time-stamp: 1714499615
 I: Building the build Environment
 I: extracting base tarball [/var/cache/pbuilder/trixie-reproducible-base.tgz]
 I: copying local configuration
@@ -25,52 +25,84 @@
 dpkg-source: info: unpacking bootstrap-flask_2.4.0+ds-1.debian.tar.xz
 I: Not using root during the build.
 I: Installing the build-deps
-I: user script /srv/workspace/pbuilder/3989860/tmp/hooks/D02_print_environment starting
+I: user script /srv/workspace/pbuilder/2494673/tmp/hooks/D01_modify_environment starting
+debug: Running on codethink02-arm64.
+I: Changing host+domainname to test build reproducibility
+I: Adding a custom variable just for the fun of it...
+I: Changing /bin/sh to bash
+'/bin/sh' -> '/bin/bash'
+lrwxrwxrwx 1 root root 9 Apr 30 17:53 /bin/sh -> /bin/bash
+I: Setting pbuilder2's login shell to /bin/bash
+I: Setting pbuilder2's GECOS to second user,second room,second work-phone,second home-phone,second other
+I: user script /srv/workspace/pbuilder/2494673/tmp/hooks/D01_modify_environment finished
+I: user script /srv/workspace/pbuilder/2494673/tmp/hooks/D02_print_environment starting
 I: set
-  BUILDDIR='/build/reproducible-path'
-  BUILDUSERGECOS='first user,first room,first work-phone,first home-phone,first other'
-  BUILDUSERNAME='pbuilder1'
-  BUILD_ARCH='arm64'
-  DEBIAN_FRONTEND='noninteractive'
+  BASH=/bin/sh
+  BASHOPTS=checkwinsize:cmdhist:complete_fullquote:extquote:force_fignore:globasciiranges:globskipdots:hostcomplete:interactive_comments:patsub_replacement:progcomp:promptvars:sourcepath
+  BASH_ALIASES=()
+  BASH_ARGC=()
+  BASH_ARGV=()
+  BASH_CMDS=()
+  BASH_LINENO=([0]="12" [1]="0")
+  BASH_LOADABLES_PATH=/usr/local/lib/bash:/usr/lib/bash:/opt/local/lib/bash:/usr/pkg/lib/bash:/opt/pkg/lib/bash:.
+  BASH_SOURCE=([0]="/tmp/hooks/D02_print_environment" [1]="/tmp/hooks/D02_print_environment")
+  BASH_VERSINFO=([0]="5" [1]="2" [2]="21" [3]="1" [4]="release" [5]="aarch64-unknown-linux-gnu")
+  BASH_VERSION='5.2.21(1)-release'
+  BUILDDIR=/build/reproducible-path
+  BUILDUSERGECOS='second user,second room,second work-phone,second home-phone,second other'
+  BUILDUSERNAME=pbuilder2
+  BUILD_ARCH=arm64
+  DEBIAN_FRONTEND=noninteractive
   DEB_BUILD_OPTIONS='buildinfo=+all reproducible=+all parallel=12 '
-  DISTRIBUTION='trixie'
-  HOME='/root'
-  HOST_ARCH='arm64'
+  DIRSTACK=()
+  DISTRIBUTION=trixie
+  EUID=0
+  FUNCNAME=([0]="Echo" [1]="main")
+  GROUPS=()
+  HOME=/root
+  HOSTNAME=i-capture-the-hostname
+  HOSTTYPE=aarch64
+  HOST_ARCH=arm64
   IFS=' 	
   '
-  INVOCATION_ID='e8c5c25afadd44b6a182fda9d3c89bd9'
-  LANG='C'
-  LANGUAGE='en_US:en'
-  LC_ALL='C'
-  MAIL='/var/mail/root'
-  OPTIND='1'
-  PATH='/usr/sbin:/usr/bin:/sbin:/bin:/usr/games'
-  PBCURRENTCOMMANDLINEOPERATION='build'
-  PBUILDER_OPERATION='build'
-  PBUILDER_PKGDATADIR='/usr/share/pbuilder'
-  PBUILDER_PKGLIBDIR='/usr/lib/pbuilder'
-  PBUILDER_SYSCONFDIR='/etc'
-  PPID='3989860'
-  PS1='# '
-  PS2='> '
+  INVOCATION_ID=a7f3a20384f94e59881150ea2c211b49
+  LANG=C
+  LANGUAGE=nl_BE:nl
+  LC_ALL=C
+  MACHTYPE=aarch64-unknown-linux-gnu
+  MAIL=/var/mail/root
+  OPTERR=1
+  OPTIND=1
+  OSTYPE=linux-gnu
+  PATH=/usr/sbin:/usr/bin:/sbin:/bin:/usr/games:/i/capture/the/path
+  PBCURRENTCOMMANDLINEOPERATION=build
+  PBUILDER_OPERATION=build
+  PBUILDER_PKGDATADIR=/usr/share/pbuilder
+  PBUILDER_PKGLIBDIR=/usr/lib/pbuilder
+  PBUILDER_SYSCONFDIR=/etc
+  PIPESTATUS=([0]="0")
+  POSIXLY_CORRECT=y
+  PPID=2494673
   PS4='+ '
-  PWD='/'
-  SHELL='/bin/bash'
-  SHLVL='2'
-  SUDO_COMMAND='/usr/bin/timeout -k 18.1h 18h /usr/bin/ionice -c 3 /usr/bin/nice /usr/sbin/pbuilder --build --configfile /srv/reproducible-results/rbuild-debian/r-b-build.1WnQFbc6/pbuilderrc_iYFE --distribution trixie --hookdir /etc/pbuilder/first-build-hooks --debbuildopts -b --basetgz /var/cache/pbuilder/trixie-reproducible-base.tgz --buildresult /srv/reproducible-results/rbuild-debian/r-b-build.1WnQFbc6/b1 --logfile b1/build.log bootstrap-flask_2.4.0+ds-1.dsc'
-  SUDO_GID='109'
-  SUDO_UID='104'
-  SUDO_USER='jenkins'
-  TERM='unknown'
-  TZ='/usr/share/zoneinfo/Etc/GMT+12'
-  USER='root'
-  _='/usr/bin/systemd-run'
-  http_proxy='http://192.168.101.4:3128'
+  PWD=/
+  SHELL=/bin/bash
+  SHELLOPTS=braceexpand:errexit:hashall:interactive-comments:posix
+  SHLVL=3
+  SUDO_COMMAND='/usr/bin/timeout -k 24.1h 24h /usr/bin/ionice -c 3 /usr/bin/nice -n 11 /usr/bin/unshare --uts -- /usr/sbin/pbuilder --build --configfile /srv/reproducible-results/rbuild-debian/r-b-build.1WnQFbc6/pbuilderrc_wcta --distribution trixie --hookdir /etc/pbuilder/rebuild-hooks --debbuildopts -b --basetgz /var/cache/pbuilder/trixie-reproducible-base.tgz --buildresult /srv/reproducible-results/rbuild-debian/r-b-build.1WnQFbc6/b2 --logfile b2/build.log bootstrap-flask_2.4.0+ds-1.dsc'
+  SUDO_GID=109
+  SUDO_UID=104
+  SUDO_USER=jenkins
+  TERM=unknown
+  TZ=/usr/share/zoneinfo/Etc/GMT-14
+  UID=0
+  USER=root
+  _='I: set'
+  http_proxy=http://192.168.101.4:3128
 I: uname -a
-  Linux codethink03-arm64 6.1.0-20-cloud-arm64 #1 SMP Debian 6.1.85-1 (2024-04-11) aarch64 GNU/Linux
+  Linux i-capture-the-hostname 6.1.0-20-cloud-arm64 #1 SMP Debian 6.1.85-1 (2024-04-11) aarch64 GNU/Linux
 I: ls -l /bin
-  lrwxrwxrwx 1 root root 7 May 24 13:38 /bin -> usr/bin
-I: user script /srv/workspace/pbuilder/3989860/tmp/hooks/D02_print_environment finished
+  lrwxrwxrwx 1 root root 7 Apr 21 07:15 /bin -> usr/bin
+I: user script /srv/workspace/pbuilder/2494673/tmp/hooks/D02_print_environment finished
  -> Attempting to satisfy build-dependencies
  -> Creating pbuilder-satisfydepends-dummy package
 Package: pbuilder-satisfydepends-dummy
@@ -340,7 +372,7 @@
 Get: 103 http://deb.debian.org/debian trixie/main arm64 python3-pallets-sphinx-themes all 2.1.1-1 [22.0 kB]
 Get: 104 http://deb.debian.org/debian trixie/main arm64 python3-pluggy all 1.5.0-1 [26.9 kB]
 Get: 105 http://deb.debian.org/debian trixie/main arm64 python3-pytest all 7.4.4-3 [239 kB]
-Fetched 47.4 MB in 0s (134 MB/s)
+Fetched 47.4 MB in 0s (181 MB/s)
 debconf: delaying package configuration, since apt-utils is not installed
 dpkg: libdb5.3:arm64: dependency problems, but removing anyway as you requested:
  libperl5.38:arm64 depends on libdb5.3.
@@ -701,8 +733,8 @@
 Setting up tzdata (2024a-3) ...
 
 Current default time zone: 'Etc/UTC'
-Local time is now:      Tue Jun  3 00:14:39 UTC 2025.
-Universal Time is now:  Tue Jun  3 00:14:39 UTC 2025.
+Local time is now:      Tue Apr 30 17:53:58 UTC 2024.
+Universal Time is now:  Tue Apr 30 17:53:58 UTC 2024.
 Run 'dpkg-reconfigure tzdata' if you wish to change it.
 
 Setting up autotools-dev (20220109.1) ...
@@ -812,7 +844,11 @@
 Building tag database...
  -> Finished parsing the build-deps
 I: Building the package
-I: Running cd /build/reproducible-path/bootstrap-flask-2.4.0+ds/ && env PATH="/usr/sbin:/usr/bin:/sbin:/bin:/usr/games" HOME="/nonexistent/first-build" dpkg-buildpackage -us -uc -b && env PATH="/usr/sbin:/usr/bin:/sbin:/bin:/usr/games" HOME="/nonexistent/first-build" dpkg-genchanges -S  > ../bootstrap-flask_2.4.0+ds-1_source.changes
+I: user script /srv/workspace/pbuilder/2494673/tmp/hooks/A99_set_merged_usr starting
+Not re-configuring usrmerge for trixie
+I: user script /srv/workspace/pbuilder/2494673/tmp/hooks/A99_set_merged_usr finished
+hostname: Name or service not known
+I: Running cd /build/reproducible-path/bootstrap-flask-2.4.0+ds/ && env PATH="/usr/sbin:/usr/bin:/sbin:/bin:/usr/games:/i/capture/the/path" HOME="/nonexistent/second-build" dpkg-buildpackage -us -uc -b && env PATH="/usr/sbin:/usr/bin:/sbin:/bin:/usr/games:/i/capture/the/path" HOME="/nonexistent/second-build" dpkg-genchanges -S  > ../bootstrap-flask_2.4.0+ds-1_source.changes
 dpkg-buildpackage: info: source package bootstrap-flask
 dpkg-buildpackage: info: source version 2.4.0+ds-1
 dpkg-buildpackage: info: source distribution unstable
@@ -1422,7 +1458,7 @@
 Copying Bootstrap_Flask.egg-info to build/bdist.linux-aarch64/wheel/Bootstrap_Flask-2.4.0.egg-info
 running install_scripts
 creating build/bdist.linux-aarch64/wheel/Bootstrap_Flask-2.4.0.dist-info/WHEEL
-creating '/build/reproducible-path/bootstrap-flask-2.4.0+ds/.pybuild/cpython3_3.12_flask-bootstrap/.tmp-4fyo9tw1/Bootstrap_Flask-2.4.0-py3-none-any.whl' and adding 'build/bdist.linux-aarch64/wheel' to it
+creating '/build/reproducible-path/bootstrap-flask-2.4.0+ds/.pybuild/cpython3_3.12_flask-bootstrap/.tmp-dmofuln1/Bootstrap_Flask-2.4.0-py3-none-any.whl' and adding 'build/bdist.linux-aarch64/wheel' to it
 adding 'flask_bootstrap/__init__.py'
 adding 'flask_bootstrap/static/bootstrap4/jquery.min.map'
 adding 'flask_bootstrap/static/bootstrap4/css/bootstrap.min.css'
@@ -1951,7 +1987,7 @@
 Copying Bootstrap_Flask.egg-info to build/bdist.linux-aarch64/wheel/Bootstrap_Flask-2.4.0.egg-info
 running install_scripts
 creating build/bdist.linux-aarch64/wheel/Bootstrap_Flask-2.4.0.dist-info/WHEEL
-creating '/build/reproducible-path/bootstrap-flask-2.4.0+ds/.pybuild/cpython3_3.11_flask-bootstrap/.tmp-82h8krja/Bootstrap_Flask-2.4.0-py3-none-any.whl' and adding 'build/bdist.linux-aarch64/wheel' to it
+creating '/build/reproducible-path/bootstrap-flask-2.4.0+ds/.pybuild/cpython3_3.11_flask-bootstrap/.tmp-6no99nrr/Bootstrap_Flask-2.4.0-py3-none-any.whl' and adding 'build/bdist.linux-aarch64/wheel' to it
 adding 'flask_bootstrap/__init__.py'
 adding 'flask_bootstrap/static/bootstrap4/jquery.min.map'
 adding 'flask_bootstrap/static/bootstrap4/css/bootstrap.min.css'
@@ -2232,7 +2268,7 @@
     return __obj(*args, **kwargs)
 
 -- Docs: https://docs.pytest.org/en/stable/how-to/capture-warnings.html
-======================== 119 passed, 1 warning in 2.58s ========================
+======================== 119 passed, 1 warning in 2.29s ========================
 I: pybuild base:311: cd /build/reproducible-path/bootstrap-flask-2.4.0+ds/.pybuild/cpython3_3.11_flask-bootstrap/build; python3.11 -m pytest --ignore=tests/test_bootstrap4/test_render_form.py --ignore=tests/test_bootstrap5/test_render_form.py --ignore=tests/test_bootstrap4/test_bootstrap.py --ignore=tests/test_bootstrap5/test_bootstrap5.py
 ============================= test session starts ==============================
 platform linux -- Python 3.11.9, pytest-7.4.4, pluggy-1.5.0
@@ -2265,7 +2301,7 @@
     return __obj(*args, **kwargs)
 
 -- Docs: https://docs.pytest.org/en/stable/how-to/capture-warnings.html
-======================== 119 passed, 1 warning in 2.86s ========================
+======================== 119 passed, 1 warning in 2.58s ========================
    create-stamp debian/debhelper-build-stamp
    dh_testroot -O--buildsystem=pybuild
    dh_prep -O--buildsystem=pybuild
@@ -2291,8 +2327,8 @@
    dh_missing -O--buildsystem=pybuild
    dh_installdeb -O--buildsystem=pybuild
    dh_gencontrol -O--buildsystem=pybuild
-dpkg-gencontrol: warning: package python-flask-bootstrap-doc: substitution variable ${sphinxdoc:Built-Using} unused, but is defined
 dpkg-gencontrol: warning: Depends field of package python3-flask-bootstrap: substitution variable ${shlibs:Depends} used, but is not defined
+dpkg-gencontrol: warning: package python-flask-bootstrap-doc: substitution variable ${sphinxdoc:Built-Using} unused, but is defined
    dh_md5sums -O--buildsystem=pybuild
    dh_builddeb -O--buildsystem=pybuild
 dpkg-deb: building package 'python3-flask-bootstrap' in '../python3-flask-bootstrap_2.4.0+ds-1_all.deb'.
@@ -2304,12 +2340,14 @@
 dpkg-buildpackage: info: binary-only upload (no source included)
 dpkg-genchanges: info: including full source code in upload
 I: copying local configuration
+I: user script /srv/workspace/pbuilder/2494673/tmp/hooks/B01_cleanup starting
+I: user script /srv/workspace/pbuilder/2494673/tmp/hooks/B01_cleanup finished
 I: unmounting dev/ptmx filesystem
 I: unmounting dev/pts filesystem
 I: unmounting dev/shm filesystem
 I: unmounting proc filesystem
 I: unmounting sys filesystem
 I: cleaning the build env 
-I: removing directory /srv/workspace/pbuilder/3989860 and its subdirectories
-I: Current time: Mon Jun  2 12:16:31 -12 2025
-I: pbuilder-time-stamp: 1748909791
+I: removing directory /srv/workspace/pbuilder/2494673 and its subdirectories
+I: Current time: Wed May  1 07:55:09 +14 2024
+I: pbuilder-time-stamp: 1714499709