Diff of the two buildlogs:

--
--- b1/build.log	2025-03-17 19:47:51.431818709 +0000
+++ b2/build.log	2025-03-17 20:07:11.367961228 +0000
@@ -1,6 +1,6 @@
 I: pbuilder: network access will be disabled during build
-I: Current time: Mon Mar 17 07:47:17 -12 2025
-I: pbuilder-time-stamp: 1742240837
+I: Current time: Mon Apr 20 16:12:31 +14 2026
+I: pbuilder-time-stamp: 1776651151
 I: Building the build Environment
 I: extracting base tarball [/var/cache/pbuilder/unstable-reproducible-base.tgz]
 I: copying local configuration
@@ -24,54 +24,86 @@
 dpkg-source: info: unpacking install-mimic_0.4.2-1.debian.tar.xz
 I: using fakeroot in build.
 I: Installing the build-deps
-I: user script /srv/workspace/pbuilder/45343/tmp/hooks/D02_print_environment starting
+I: user script /srv/workspace/pbuilder/127855/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 Apr 20 02:20 /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/127855/tmp/hooks/D01_modify_environment finished
+I: user script /srv/workspace/pbuilder/127855/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]="37" [3]="1" [4]="release" [5]="i686-pc-linux-gnu")
+  BASH_VERSION='5.2.37(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='39dad7de2fb64165b8b4d7b8ba45b70a'
-  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='45343'
-  PS1='# '
-  PS2='> '
+  INVOCATION_ID=8f412e812fcb4df6be8ac06eabd6d1d2
+  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=127855
   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.6ra0omjX/pbuilderrc_N7cb --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.6ra0omjX/b1 --logfile b1/build.log install-mimic_0.4.2-1.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.6ra0omjX/pbuilderrc_EzqO --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.6ra0omjX/b2 --logfile b2/build.log install-mimic_0.4.2-1.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 ionos2-i386 6.1.0-32-amd64 #1 SMP PREEMPT_DYNAMIC Debian 6.1.129-1 (2025-03-06) x86_64 GNU/Linux
+  Linux i-capture-the-hostname 6.1.0-32-amd64 #1 SMP PREEMPT_DYNAMIC Debian 6.1.129-1 (2025-03-06) x86_64 GNU/Linux
 I: ls -l /bin
-  lrwxrwxrwx 1 root root 7 Mar  4 11:20 /bin -> usr/bin
-I: user script /srv/workspace/pbuilder/45343/tmp/hooks/D02_print_environment finished
+  lrwxrwxrwx 1 root root 7 Mar  4  2025 /bin -> usr/bin
+I: user script /srv/workspace/pbuilder/127855/tmp/hooks/D02_print_environment finished
  -> Attempting to satisfy build-dependencies
  -> Creating pbuilder-satisfydepends-dummy package
 Package: pbuilder-satisfydepends-dummy
@@ -142,7 +174,7 @@
 Get: 29 http://deb.debian.org/debian unstable/main i386 po-debconf all 1.0.21+nmu1 [248 kB]
 Get: 30 http://deb.debian.org/debian unstable/main i386 debhelper all 13.24.1 [920 kB]
 Get: 31 http://deb.debian.org/debian unstable/main i386 dh-package-notes all 0.15 [6692 B]
-Fetched 21.2 MB in 0s (85.5 MB/s)
+Fetched 21.2 MB in 1s (19.4 MB/s)
 Preconfiguring packages ...
 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 ... 19770 files and directories currently installed.)
@@ -286,7 +318,11 @@
 fakeroot is already the newest version (1.37.1-1).
 0 upgraded, 0 newly installed, 0 to remove and 0 not upgraded.
 I: Building the package
-I: Running cd /build/reproducible-path/install-mimic-0.4.2/ && 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  > ../install-mimic_0.4.2-1_source.changes
+I: user script /srv/workspace/pbuilder/127855/tmp/hooks/A99_set_merged_usr starting
+Not re-configuring usrmerge for unstable
+I: user script /srv/workspace/pbuilder/127855/tmp/hooks/A99_set_merged_usr finished
+hostname: Name or service not known
+I: Running cd /build/reproducible-path/install-mimic-0.4.2/ && 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  > ../install-mimic_0.4.2-1_source.changes
 dpkg-buildpackage: info: source package install-mimic
 dpkg-buildpackage: info: source version 0.4.2-1
 dpkg-buildpackage: info: source distribution unstable
@@ -296,7 +332,7 @@
  debian/rules clean
 dh 'clean'
    dh_auto_clean
-	make -j11 distclean
+	make -j21 distclean
 make[1]: Entering directory '/build/reproducible-path/install-mimic-0.4.2'
 rm -f install-mimic install-mimic.o install-mimic.1.gz
 [ ! -d "target" ] || cargo clean
@@ -310,37 +346,37 @@
    dh_autoreconf
    dh_auto_configure
    dh_auto_build
-	make -j11 "INSTALL=install --strip-program=true"
+	make -j21 "INSTALL=install --strip-program=true"
 make[1]: Entering directory '/build/reproducible-path/install-mimic-0.4.2'
 cc -D_LARGEFILE_SOURCE -D_FILE_OFFSET_BITS=64 -Wdate-time -D_FORTIFY_SOURCE=2 -D_POSIX_C_SOURCE=200809L -D_XOPEN_SOURCE=700  -g -O2 -Werror=implicit-function-declaration -ffile-prefix-map=/build/reproducible-path/install-mimic-0.4.2=. -fstack-protector-strong -Wformat -Werror=format-security -std=c99 -Wall -W -pedantic -Wbad-function-cast -Wcast-align -Wchar-subscripts -Winline -Wmissing-prototypes -Wnested-externs -Wpointer-arith -Wredundant-decls -Wshadow -Wstrict-prototypes -Wwrite-strings -c -o install-mimic.o install-mimic.c
 gzip -c9 -cn9 install-mimic.1 > install-mimic.1.gz || (rm -f -- install-mimic.1.gz; false)
 cc -Wl,-z,relro -Wl,-z,now -specs=/usr/share/debhelper/dh_package_notes/debian-package-notes.specs  -o install-mimic install-mimic.o 
 make[1]: Leaving directory '/build/reproducible-path/install-mimic-0.4.2'
    dh_auto_test
-	make -j11 test
+	make -j21 test
 make[1]: Entering directory '/build/reproducible-path/install-mimic-0.4.2'
 
-===== Testing the C implementation
-
-prove t
-
 ===== Testing the Perl 5 implementation
 
 [ -x install-mimic.pl ] || chmod +x install-mimic.pl
 env INSTALL_MIMIC=./install-mimic.pl prove t
+
+===== Testing the C implementation
+
+prove t
 t/01-simple.t .. ok
 All tests successful.
-Files=1, Tests=90,  0 wallclock secs ( 0.02 usr  0.00 sys +  0.18 cusr  0.04 csys =  0.24 CPU)
+Files=1, Tests=90, 18 wallclock secs ( 0.04 usr  0.02 sys +  0.14 cusr  0.32 csys =  0.52 CPU)
 Result: PASS
 t/01-simple.t .. ok
 All tests successful.
-Files=1, Tests=90,  1 wallclock secs ( 0.02 usr  0.00 sys +  0.70 cusr  0.10 csys =  0.82 CPU)
+Files=1, Tests=90, 29 wallclock secs ( 0.04 usr  0.02 sys +  0.60 cusr  0.66 csys =  1.32 CPU)
 Result: PASS
 make[1]: Leaving directory '/build/reproducible-path/install-mimic-0.4.2'
    create-stamp debian/debhelper-build-stamp
    dh_prep
    dh_auto_install --destdir=debian/install-mimic/
-	make -j11 install DESTDIR=/build/reproducible-path/install-mimic-0.4.2/debian/install-mimic AM_UPDATE_INFO_DIR=no "INSTALL=install --strip-program=true"
+	make -j21 install DESTDIR=/build/reproducible-path/install-mimic-0.4.2/debian/install-mimic AM_UPDATE_INFO_DIR=no "INSTALL=install --strip-program=true"
 make[1]: Entering directory '/build/reproducible-path/install-mimic-0.4.2'
 mkdir -p /build/reproducible-path/install-mimic-0.4.2/debian/install-mimic/usr/bin
 install -m 755 install-mimic /build/reproducible-path/install-mimic-0.4.2/debian/install-mimic/usr/bin
@@ -373,8 +409,8 @@
    dh_gencontrol
    dh_md5sums
    dh_builddeb
-dpkg-deb: building package 'install-mimic' in '../install-mimic_0.4.2-1_i386.deb'.
 dpkg-deb: building package 'install-mimic-dbgsym' in '../install-mimic-dbgsym_0.4.2-1_i386.deb'.
+dpkg-deb: building package 'install-mimic' in '../install-mimic_0.4.2-1_i386.deb'.
  dpkg-genbuildinfo --build=binary -O../install-mimic_0.4.2-1_i386.buildinfo
  dpkg-genchanges --build=binary -O../install-mimic_0.4.2-1_i386.changes
 dpkg-genchanges: info: binary-only upload (no source code included)
@@ -382,12 +418,14 @@
 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/127855/tmp/hooks/B01_cleanup starting
+I: user script /srv/workspace/pbuilder/127855/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/45343 and its subdirectories
-I: Current time: Mon Mar 17 07:47:50 -12 2025
-I: pbuilder-time-stamp: 1742240870
+I: removing directory /srv/workspace/pbuilder/127855 and its subdirectories
+I: Current time: Mon Apr 20 16:29:56 +14 2026
+I: pbuilder-time-stamp: 1776652196