Diff of the two buildlogs:

--
--- b1/build.log	2023-04-08 09:49:24.827812756 +0000
+++ b2/build.log	2023-04-08 10:01:10.344351084 +0000
@@ -1,6 +1,6 @@
 I: pbuilder: network access will be disabled during build
-I: Current time: Fri May 10 04:03:39 -12 2024
-I: pbuilder-time-stamp: 1715357019
+I: Current time: Sat Apr  8 23:49:28 +14 2023
+I: pbuilder-time-stamp: 1680947368
 I: Building the build Environment
 I: extracting base tarball [/var/cache/pbuilder/bookworm-reproducible-base.tgz]
 I: copying local configuration
@@ -16,7 +16,7 @@
 I: copying [./fonts-firacode_6.2.orig.tar.xz]
 I: copying [./fonts-firacode_6.2-2.debian.tar.xz]
 I: Extracting source
-gpgv: Signature made Thu Sep  8 19:57:42 2022 -12
+gpgv: Signature made Fri Sep  9 21:57:42 2022 +14
 gpgv:                using RSA key 22C17648A9526B84DF191C96CBEA8E970CCD59DF
 gpgv:                issuer "fabian@debian.org"
 gpgv: Can't check signature: No public key
@@ -31,11 +31,20 @@
 dpkg-source: info: applying 0029-Fixed-building-on-the-latest-fontmake.patch
 I: Not using root during the build.
 I: Installing the build-deps
-I: user script /srv/workspace/pbuilder/27400/tmp/hooks/D02_print_environment starting
+I: user script /srv/workspace/pbuilder/7982/tmp/hooks/D01_modify_environment starting
+debug: Running on codethink14-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
+lrwxrwxrwx 1 root root 4 Jan  6 03:20 /bin/sh -> dash
+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/7982/tmp/hooks/D01_modify_environment finished
+I: user script /srv/workspace/pbuilder/7982/tmp/hooks/D02_print_environment starting
 I: set
   BUILDDIR='/build'
-  BUILDUSERGECOS='first user,first room,first work-phone,first home-phone,first other'
-  BUILDUSERNAME='pbuilder1'
+  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=8'
@@ -45,38 +54,38 @@
   IFS=' 	
   '
   LANG='C'
-  LANGUAGE='en_US:en'
+  LANGUAGE='nl_BE:nl'
   LC_ALL='C'
   MAIL='/var/mail/root'
   OPTIND='1'
-  PATH='/usr/sbin:/usr/bin:/sbin:/bin:/usr/games'
+  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'
-  PPID='27400'
+  PPID='7982'
   PS1='# '
   PS2='> '
   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.ztRwGaeX/pbuilderrc_sQKs --distribution bookworm --hookdir /etc/pbuilder/first-build-hooks --debbuildopts -b --basetgz /var/cache/pbuilder/bookworm-reproducible-base.tgz --buildresult /srv/reproducible-results/rbuild-debian/r-b-build.ztRwGaeX/b1 --logfile b1/build.log fonts-firacode_6.2-2.dsc'
+  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.ztRwGaeX/pbuilderrc_KfkO --distribution bookworm --hookdir /etc/pbuilder/rebuild-hooks --debbuildopts -b --basetgz /var/cache/pbuilder/bookworm-reproducible-base.tgz --buildresult /srv/reproducible-results/rbuild-debian/r-b-build.ztRwGaeX/b2 --logfile b2/build.log --extrapackages usrmerge fonts-firacode_6.2-2.dsc'
   SUDO_GID='117'
   SUDO_UID='110'
   SUDO_USER='jenkins'
   TERM='unknown'
-  TZ='/usr/share/zoneinfo/Etc/GMT+12'
+  TZ='/usr/share/zoneinfo/Etc/GMT-14'
   USER='root'
   USERNAME='root'
   _='/usr/bin/systemd-run'
   http_proxy='http://192.168.101.16:3128'
 I: uname -a
-  Linux codethink13-arm64 4.15.0-208-generic #220-Ubuntu SMP Mon Mar 20 14:28:12 UTC 2023 aarch64 GNU/Linux
+  Linux i-capture-the-hostname 4.15.0-208-generic #220-Ubuntu SMP Mon Mar 20 14:28:12 UTC 2023 aarch64 GNU/Linux
 I: ls -l /bin
-  lrwxrwxrwx 1 root root 7 May  7 04:48 /bin -> usr/bin
-I: user script /srv/workspace/pbuilder/27400/tmp/hooks/D02_print_environment finished
+  lrwxrwxrwx 1 root root 7 Apr  8 00:26 /bin -> usr/bin
+I: user script /srv/workspace/pbuilder/7982/tmp/hooks/D02_print_environment finished
  -> Attempting to satisfy build-dependencies
  -> Creating pbuilder-satisfydepends-dummy package
 Package: pbuilder-satisfydepends-dummy
@@ -375,7 +384,7 @@
 Get: 249 http://deb.debian.org/debian bookworm/main arm64 gftools all 0.5.2+dfsg-3 [189 kB]
 Get: 250 http://deb.debian.org/debian bookworm/main arm64 sfnt2woff-zopfli arm64 1.3.1-1 [32.7 kB]
 Get: 251 http://deb.debian.org/debian bookworm/main arm64 woff2 arm64 1.0.2-2 [11.3 kB]
-Fetched 152 MB in 4s (35.4 MB/s)
+Fetched 152 MB in 3s (44.6 MB/s)
 debconf: delaying package configuration, since apt-utils is not installed
 Selecting previously unselected package libpython3.11-minimal:arm64.
 (Reading database ... 
(Reading database ... 5%
(Reading database ... 10%
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(Reading database ... 20%
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(Reading database ... 40%
(Reading database ... 45%
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(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 ... 19616 files and directories currently installed.)
@@ -1414,8 +1423,17 @@
 Writing extended state information...
 Building tag database...
  -> Finished parsing the build-deps
+Reading package lists...
+Building dependency tree...
+Reading state information...
+usrmerge is already the newest version (35).
+0 upgraded, 0 newly installed, 0 to remove and 0 not upgraded.
 I: Building the package
-I: Running cd /build/fonts-firacode-6.2/ && 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  > ../fonts-firacode_6.2-2_source.changes
+I: user script /srv/workspace/pbuilder/7982/tmp/hooks/A99_set_merged_usr starting
+Re-configuring usrmerge...
+I: user script /srv/workspace/pbuilder/7982/tmp/hooks/A99_set_merged_usr finished
+hostname: Temporary failure in name resolution
+I: Running cd /build/fonts-firacode-6.2/ && 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  > ../fonts-firacode_6.2-2_source.changes
 dpkg-buildpackage: info: source package fonts-firacode
 dpkg-buildpackage: info: source version 6.2-2
 dpkg-buildpackage: info: source distribution unstable
@@ -1446,7 +1464,7 @@
   [i] Creating distr/ttf/Fira Code/FiraCode-Light.ttf
 
 INFO:fontmake.font_project:Building master UFOs and designspace from Glyphs source
-INFO:glyphsLib.classes:Parsing "/tmp/tmp.bnJV9gkGFs.glyphs" file into <GSFont>
+INFO:glyphsLib.classes:Parsing "/tmp/tmp.mabCI2yx3F.glyphs" file into <GSFont>
 INFO:fontmake.font_project:Interpolating master UFOs from designspace
 INFO:fontmake.font_project:Generating instance UFO for "Fira Code Light"
 INFO:fontmake.font_project:Building TTF for FiraCode-Light
@@ -1563,7 +1581,7 @@
   [i] Creating distr/ttf/Fira Code/FiraCode-Regular.ttf
 
 INFO:fontmake.font_project:Building master UFOs and designspace from Glyphs source
-INFO:glyphsLib.classes:Parsing "/tmp/tmp.bnJV9gkGFs.glyphs" file into <GSFont>
+INFO:glyphsLib.classes:Parsing "/tmp/tmp.mabCI2yx3F.glyphs" file into <GSFont>
 INFO:fontmake.font_project:Interpolating master UFOs from designspace
 INFO:fontmake.font_project:Generating instance UFO for "Fira Code Regular"
 INFO:fontmake.font_project:Building TTF for FiraCode-Regular
@@ -1680,7 +1698,7 @@
   [i] Creating distr/ttf/Fira Code/FiraCode-Retina.ttf
 
 INFO:fontmake.font_project:Building master UFOs and designspace from Glyphs source
-INFO:glyphsLib.classes:Parsing "/tmp/tmp.bnJV9gkGFs.glyphs" file into <GSFont>
+INFO:glyphsLib.classes:Parsing "/tmp/tmp.mabCI2yx3F.glyphs" file into <GSFont>
 INFO:fontmake.font_project:Interpolating master UFOs from designspace
 INFO:fontmake.font_project:Generating instance UFO for "Fira Code Retina"
 INFO:fontmake.font_project:Building TTF for FiraCode-Retina
@@ -1797,7 +1815,7 @@
   [i] Creating distr/ttf/Fira Code/FiraCode-Medium.ttf
 
 INFO:fontmake.font_project:Building master UFOs and designspace from Glyphs source
-INFO:glyphsLib.classes:Parsing "/tmp/tmp.bnJV9gkGFs.glyphs" file into <GSFont>
+INFO:glyphsLib.classes:Parsing "/tmp/tmp.mabCI2yx3F.glyphs" file into <GSFont>
 INFO:fontmake.font_project:Interpolating master UFOs from designspace
 INFO:fontmake.font_project:Generating instance UFO for "Fira Code Medium"
 INFO:fontmake.font_project:Building TTF for FiraCode-Medium
@@ -1914,7 +1932,7 @@
   [i] Creating distr/ttf/Fira Code/FiraCode-SemiBold.ttf
 
 INFO:fontmake.font_project:Building master UFOs and designspace from Glyphs source
-INFO:glyphsLib.classes:Parsing "/tmp/tmp.bnJV9gkGFs.glyphs" file into <GSFont>
+INFO:glyphsLib.classes:Parsing "/tmp/tmp.mabCI2yx3F.glyphs" file into <GSFont>
 INFO:fontmake.font_project:Interpolating master UFOs from designspace
 INFO:fontmake.font_project:Generating instance UFO for "Fira Code SemiBold"
 INFO:fontmake.font_project:Building TTF for FiraCode-SemiBold
@@ -2031,7 +2049,7 @@
   [i] Creating distr/ttf/Fira Code/FiraCode-Bold.ttf
 
 INFO:fontmake.font_project:Building master UFOs and designspace from Glyphs source
-INFO:glyphsLib.classes:Parsing "/tmp/tmp.bnJV9gkGFs.glyphs" file into <GSFont>
+INFO:glyphsLib.classes:Parsing "/tmp/tmp.mabCI2yx3F.glyphs" file into <GSFont>
 INFO:fontmake.font_project:Interpolating master UFOs from designspace
 INFO:fontmake.font_project:Generating instance UFO for "Fira Code Bold"
 INFO:fontmake.font_project:Building TTF for FiraCode-Bold
@@ -2148,7 +2166,7 @@
   [i] Creating variable font file!
 
 INFO:fontmake.font_project:Building master UFOs and designspace from Glyphs source
-INFO:glyphsLib.classes:Parsing "/tmp/tmp.2nwKLyxOuK.glyphs" file into <GSFont>
+INFO:glyphsLib.classes:Parsing "/tmp/tmp.GcbelGl56r.glyphs" file into <GSFont>
 INFO:fontmake.font_project:Building variable font distr/variable_ttf/Fira Code/FiraCode-VF.ttf
 INFO:ufo2ft:Pre-processing glyphs
 INFO:ufo2ft.filters:Running EraseOpenCornersFilter on FiraCode-Light
@@ -2466,12 +2484,14 @@
 dpkg-buildpackage: info: binary-only upload (no source included)
 dpkg-genchanges: info: not including original source code in upload
 I: copying local configuration
+I: user script /srv/workspace/pbuilder/7982/tmp/hooks/B01_cleanup starting
+I: user script /srv/workspace/pbuilder/7982/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/27400 and its subdirectories
-I: Current time: Fri May 10 04:12:23 -12 2024
-I: pbuilder-time-stamp: 1715357543
+I: removing directory /srv/workspace/pbuilder/7982 and its subdirectories
+I: Current time: Sun Apr  9 00:01:09 +14 2023
+I: pbuilder-time-stamp: 1680948069