Diff of the two buildlogs:

--
--- b1/build.log	2024-11-16 02:30:09.395763412 +0000
+++ b2/build.log	2024-11-16 02:32:51.124476595 +0000
@@ -1,6 +1,6 @@
 I: pbuilder: network access will be disabled during build
-I: Current time: Fri Nov 15 14:29:34 -12 2024
-I: pbuilder-time-stamp: 1731724174
+I: Current time: Fri Dec 19 22:53:14 +14 2025
+I: pbuilder-time-stamp: 1766134394
 I: Building the build Environment
 I: extracting base tarball [/var/cache/pbuilder/unstable-reproducible-base.tgz]
 I: copying local configuration
@@ -26,54 +26,86 @@
 dpkg-source: info: unpacking libmarc-schema-perl_0.16-1.debian.tar.xz
 I: Not using root during the build.
 I: Installing the build-deps
-I: user script /srv/workspace/pbuilder/48007/tmp/hooks/D02_print_environment starting
+I: user script /srv/workspace/pbuilder/78200/tmp/hooks/D01_modify_environment starting
+debug: Running on ionos16-i386.
+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 Dec 19 08:54 /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/78200/tmp/hooks/D01_modify_environment finished
+I: user script /srv/workspace/pbuilder/78200/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='i386'
-  DEBIAN_FRONTEND='noninteractive'
-  DEB_BUILD_OPTIONS='buildinfo=+all reproducible=+all parallel=11 '
-  DISTRIBUTION='unstable'
-  HOME='/root'
-  HOST_ARCH='i386'
+  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]="32" [3]="1" [4]="release" [5]="i686-pc-linux-gnu")
+  BASH_VERSION='5.2.32(1)-release'
+  BUILDDIR=/build/reproducible-path
+  BUILDUSERGECOS='second user,second room,second work-phone,second home-phone,second other'
+  BUILDUSERNAME=pbuilder2
+  BUILD_ARCH=i386
+  DEBIAN_FRONTEND=noninteractive
+  DEB_BUILD_OPTIONS='buildinfo=+all reproducible=+all parallel=21 '
+  DIRSTACK=()
+  DISTRIBUTION=unstable
+  EUID=0
+  FUNCNAME=([0]="Echo" [1]="main")
+  GROUPS=()
+  HOME=/root
+  HOSTNAME=i-capture-the-hostname
+  HOSTTYPE=i686
+  HOST_ARCH=i386
   IFS=' 	
   '
-  INVOCATION_ID='6e2d8cd3de8a42e3bb4effc56cde1b83'
-  LANG='C'
-  LANGUAGE='en_US:en'
-  LC_ALL='C'
-  LD_LIBRARY_PATH='/usr/lib/libeatmydata'
-  LD_PRELOAD='libeatmydata.so'
-  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='48007'
-  PS1='# '
-  PS2='> '
+  INVOCATION_ID=26d690952aed485e9faacf97de4e5322
+  LANG=C
+  LANGUAGE=de_CH:de
+  LC_ALL=C
+  LD_LIBRARY_PATH=/usr/lib/libeatmydata
+  LD_PRELOAD=libeatmydata.so
+  MACHTYPE=i686-pc-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=78200
   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.cK6ZJjYL/pbuilderrc_5ZT1 --distribution unstable --hookdir /etc/pbuilder/first-build-hooks --debbuildopts -b --basetgz /var/cache/pbuilder/unstable-reproducible-base.tgz --buildresult /srv/reproducible-results/rbuild-debian/r-b-build.cK6ZJjYL/b1 --logfile b1/build.log libmarc-schema-perl_0.16-1.dsc'
-  SUDO_GID='112'
-  SUDO_UID='107'
-  SUDO_USER='jenkins'
-  TERM='unknown'
-  TZ='/usr/share/zoneinfo/Etc/GMT+12'
-  USER='root'
-  _='/usr/bin/systemd-run'
-  http_proxy='http://46.16.76.132:3128'
+  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.cK6ZJjYL/pbuilderrc_AT1h --distribution unstable --hookdir /etc/pbuilder/rebuild-hooks --debbuildopts -b --basetgz /var/cache/pbuilder/unstable-reproducible-base.tgz --buildresult /srv/reproducible-results/rbuild-debian/r-b-build.cK6ZJjYL/b2 --logfile b2/build.log libmarc-schema-perl_0.16-1.dsc'
+  SUDO_GID=112
+  SUDO_UID=107
+  SUDO_USER=jenkins
+  TERM=unknown
+  TZ=/usr/share/zoneinfo/Etc/GMT-14
+  UID=0
+  USER=root
+  _='I: set'
+  http_proxy=http://213.165.73.152:3128
 I: uname -a
-  Linux ionos12-i386 6.1.0-27-amd64 #1 SMP PREEMPT_DYNAMIC Debian 6.1.115-1 (2024-11-01) x86_64 GNU/Linux
+  Linux i-capture-the-hostname 6.1.0-27-amd64 #1 SMP PREEMPT_DYNAMIC Debian 6.1.115-1 (2024-11-01) x86_64 GNU/Linux
 I: ls -l /bin
-  lrwxrwxrwx 1 root root 7 Aug  4 21:30 /bin -> usr/bin
-I: user script /srv/workspace/pbuilder/48007/tmp/hooks/D02_print_environment finished
+  lrwxrwxrwx 1 root root 7 Aug  4  2024 /bin -> usr/bin
+I: user script /srv/workspace/pbuilder/78200/tmp/hooks/D02_print_environment finished
  -> Attempting to satisfy build-dependencies
  -> Creating pbuilder-satisfydepends-dummy package
 Package: pbuilder-satisfydepends-dummy
@@ -177,7 +209,7 @@
 Get: 50 http://deb.debian.org/debian unstable/main i386 libprobe-perl-perl all 0.03-3 [8656 B]
 Get: 51 http://deb.debian.org/debian unstable/main i386 libtest-script-perl all 1.29-2 [14.6 kB]
 Get: 52 http://deb.debian.org/debian unstable/main i386 libtest2-suite-perl all 0.000163-1 [383 kB]
-Fetched 21.3 MB in 0s (54.7 MB/s)
+Fetched 21.3 MB in 5s (4055 kB/s)
 debconf: delaying package configuration, since apt-utils is not installed
 Selecting previously unselected package sensible-utils.
 (Reading database ... 
(Reading database ... 5%
(Reading database ... 10%
(Reading database ... 15%
(Reading database ... 20%
(Reading database ... 25%
(Reading database ... 30%
(Reading database ... 35%
(Reading database ... 40%
(Reading database ... 45%
(Reading database ... 50%
(Reading database ... 55%
(Reading database ... 60%
(Reading database ... 65%
(Reading database ... 70%
(Reading database ... 75%
(Reading database ... 80%
(Reading database ... 85%
(Reading database ... 90%
(Reading database ... 95%
(Reading database ... 100%
(Reading database ... 19952 files and directories currently installed.)
@@ -409,7 +441,11 @@
 Building tag database...
  -> Finished parsing the build-deps
 I: Building the package
-I: Running cd /build/reproducible-path/libmarc-schema-perl-0.16/ && 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  > ../libmarc-schema-perl_0.16-1_source.changes
+I: user script /srv/workspace/pbuilder/78200/tmp/hooks/A99_set_merged_usr starting
+Not re-configuring usrmerge for unstable
+I: user script /srv/workspace/pbuilder/78200/tmp/hooks/A99_set_merged_usr finished
+hostname: Name or service not known
+I: Running cd /build/reproducible-path/libmarc-schema-perl-0.16/ && 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  > ../libmarc-schema-perl_0.16-1_source.changes
 dpkg-buildpackage: info: source package libmarc-schema-perl
 dpkg-buildpackage: info: source version 0.16-1
 dpkg-buildpackage: info: source distribution unstable
@@ -428,9 +464,9 @@
 Creating new 'Build' script for 'MARC-Schema' version '0.16'
    dh_auto_build
 	/usr/bin/perl Build
-cp share/marc-schema.json blib/lib/auto/share/dist/MARC-Schema/marc-schema.json
-cp script/marcvalidate blib/script/marcvalidate
 cp lib/MARC/Schema.pm blib/lib/MARC/Schema.pm
+cp script/marcvalidate blib/script/marcvalidate
+cp share/marc-schema.json blib/lib/auto/share/dist/MARC-Schema/marc-schema.json
    dh_auto_test
 	/usr/bin/perl Build test --verbose 1
 t/MARC-Schema.t ........ 
@@ -466,7 +502,7 @@
 1..2
 ok
 t/marcvalidate.t ....... 
-# Seeded srand with seed '20241116' from local date.
+# Seeded srand with seed '20251219' from local date.
 ok 1 - Script script/marcvalidate compiles
 ok 2 - Script script/marcvalidate runs
 ok 3 - Script script/marcvalidate runs
@@ -474,7 +510,7 @@
 1..4
 ok
 All tests successful.
-Files=4, Tests=29,  2 wallclock secs ( 0.04 usr  0.02 sys +  1.44 cusr  0.20 csys =  1.70 CPU)
+Files=4, Tests=29,  6 wallclock secs ( 0.02 usr  0.00 sys +  1.56 cusr  0.24 csys =  1.82 CPU)
 Result: PASS
    create-stamp debian/debhelper-build-stamp
    dh_prep
@@ -510,12 +546,14 @@
 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/78200/tmp/hooks/B01_cleanup starting
+I: user script /srv/workspace/pbuilder/78200/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/48007 and its subdirectories
-I: Current time: Fri Nov 15 14:30:08 -12 2024
-I: pbuilder-time-stamp: 1731724208
+I: removing directory /srv/workspace/pbuilder/78200 and its subdirectories
+I: Current time: Fri Dec 19 22:55:45 +14 2025
+I: pbuilder-time-stamp: 1766134545