Diff of the two buildlogs:

--
--- b1/build.log	2025-03-11 17:39:32.381173360 +0000
+++ b2/build.log	2025-03-11 17:44:50.958785754 +0000
@@ -1,6 +1,6 @@
 I: pbuilder: network access will be disabled during build
-I: Current time: Mon Apr 13 12:00:27 -12 2026
-I: pbuilder-time-stamp: 1776124827
+I: Current time: Wed Mar 12 07:39:35 +14 2025
+I: pbuilder-time-stamp: 1741714775
 I: Building the build Environment
 I: extracting base tarball [/var/cache/pbuilder/trixie-reproducible-base.tgz]
 I: copying local configuration
@@ -22,52 +22,84 @@
 dpkg-source: info: unpacking golang-github-juju-qthttptest_0.1.3-1.debian.tar.xz
 I: Not using root during the build.
 I: Installing the build-deps
-I: user script /srv/workspace/pbuilder/1905293/tmp/hooks/D02_print_environment starting
+I: user script /srv/workspace/pbuilder/2299167/tmp/hooks/D01_modify_environment starting
+debug: Running on ionos11-amd64.
+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 Mar 11 17:39 /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/2299167/tmp/hooks/D01_modify_environment finished
+I: user script /srv/workspace/pbuilder/2299167/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='amd64'
-  DEBIAN_FRONTEND='noninteractive'
-  DEB_BUILD_OPTIONS='buildinfo=+all reproducible=+all parallel=42 '
-  DISTRIBUTION='trixie'
-  HOME='/root'
-  HOST_ARCH='amd64'
+  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]="x86_64-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=amd64
+  DEBIAN_FRONTEND=noninteractive
+  DEB_BUILD_OPTIONS='buildinfo=+all reproducible=+all parallel=20 '
+  DIRSTACK=()
+  DISTRIBUTION=trixie
+  EUID=0
+  FUNCNAME=([0]="Echo" [1]="main")
+  GROUPS=()
+  HOME=/root
+  HOSTNAME=i-capture-the-hostname
+  HOSTTYPE=x86_64
+  HOST_ARCH=amd64
   IFS=' 	
   '
-  INVOCATION_ID='d2575939ec43445fbd1b2814ca6dc1a9'
-  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='1905293'
-  PS1='# '
-  PS2='> '
+  INVOCATION_ID=49fe577f279d4589b6f0cd9c98f545a5
+  LANG=C
+  LANGUAGE=et_EE:et
+  LC_ALL=C
+  MACHTYPE=x86_64-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=2299167
   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.Oj00WkXM/pbuilderrc_91RK --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.Oj00WkXM/b1 --logfile b1/build.log golang-github-juju-qthttptest_0.1.3-1.dsc'
-  SUDO_GID='111'
-  SUDO_UID='106'
-  SUDO_USER='jenkins'
-  TERM='unknown'
-  TZ='/usr/share/zoneinfo/Etc/GMT+12'
-  USER='root'
-  _='/usr/bin/systemd-run'
-  http_proxy='http://213.165.73.152:3128'
+  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.Oj00WkXM/pbuilderrc_TbMq --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.Oj00WkXM/b2 --logfile b2/build.log golang-github-juju-qthttptest_0.1.3-1.dsc'
+  SUDO_GID=111
+  SUDO_UID=106
+  SUDO_USER=jenkins
+  TERM=unknown
+  TZ=/usr/share/zoneinfo/Etc/GMT-14
+  UID=0
+  USER=root
+  _='I: set'
+  http_proxy=http://46.16.76.132:3128
 I: uname -a
-  Linux ionos15-amd64 6.12.12+bpo-amd64 #1 SMP PREEMPT_DYNAMIC Debian 6.12.12-1~bpo12+1 (2025-02-23) x86_64 GNU/Linux
+  Linux i-capture-the-hostname 6.1.0-31-amd64 #1 SMP PREEMPT_DYNAMIC Debian 6.1.128-1 (2025-02-07) x86_64 GNU/Linux
 I: ls -l /bin
-  lrwxrwxrwx 1 root root 7 Mar  4  2025 /bin -> usr/bin
-I: user script /srv/workspace/pbuilder/1905293/tmp/hooks/D02_print_environment finished
+  lrwxrwxrwx 1 root root 7 Mar  4 11:20 /bin -> usr/bin
+I: user script /srv/workspace/pbuilder/2299167/tmp/hooks/D02_print_environment finished
  -> Attempting to satisfy build-dependencies
  -> Creating pbuilder-satisfydepends-dummy package
 Package: pbuilder-satisfydepends-dummy
@@ -172,7 +204,7 @@
 Get: 57 http://deb.debian.org/debian trixie/main amd64 libsasl2-dev amd64 2.1.28+dfsg1-9 [234 kB]
 Get: 58 http://deb.debian.org/debian trixie/main amd64 golang-gopkg-mgo.v2-dev all 2016.08.01-7 [316 kB]
 Get: 59 http://deb.debian.org/debian trixie/main amd64 golang-gopkg-yaml.v3-dev all 3.0.1-3 [74.3 kB]
-Fetched 83.1 MB in 7s (11.3 MB/s)
+Fetched 83.1 MB in 5s (17.1 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 ... 19800 files and directories currently installed.)
@@ -423,7 +455,11 @@
 Building tag database...
  -> Finished parsing the build-deps
 I: Building the package
-I: Running cd /build/reproducible-path/golang-github-juju-qthttptest-0.1.3/ && 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  > ../golang-github-juju-qthttptest_0.1.3-1_source.changes
+I: user script /srv/workspace/pbuilder/2299167/tmp/hooks/A99_set_merged_usr starting
+Not re-configuring usrmerge for trixie
+I: user script /srv/workspace/pbuilder/2299167/tmp/hooks/A99_set_merged_usr finished
+hostname: Name or service not known
+I: Running cd /build/reproducible-path/golang-github-juju-qthttptest-0.1.3/ && 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  > ../golang-github-juju-qthttptest_0.1.3-1_source.changes
 dpkg-buildpackage: info: source package golang-github-juju-qthttptest
 dpkg-buildpackage: info: source version 0.1.3-1
 dpkg-buildpackage: info: source distribution unstable
@@ -441,203 +477,203 @@
    dh_autoreconf -O--builddirectory=_build -O--buildsystem=golang
    dh_auto_configure -O--builddirectory=_build -O--buildsystem=golang
    dh_auto_build -O--builddirectory=_build -O--buildsystem=golang
-	cd _build && go install -trimpath -v -p 42 github.com/juju/qthttptest
-math/bits
+	cd _build && go install -trimpath -v -p 20 github.com/juju/qthttptest
+internal/goarch
 internal/itoa
-log/internal
-internal/asan
 encoding
-vendor/golang.org/x/crypto/internal/alias
-unicode/utf16
-internal/godebugs
-crypto/internal/fips140/alias
-internal/unsafeheader
-internal/goarch
-internal/profilerecord
-vendor/golang.org/x/crypto/cryptobyte/asn1
 cmp
-container/list
-internal/coverage/rtcov
-internal/msan
-internal/runtime/syscall
-internal/byteorder
-internal/goos
-internal/nettrace
+internal/unsafeheader
 unicode/utf8
-github.com/google/go-cmp/cmp/internal/flags
-unicode
-crypto/internal/boring/sig
+internal/coverage/rtcov
+internal/profilerecord
 internal/cpu
+math/bits
+unicode
+internal/asan
+internal/byteorder
+internal/godebugs
+internal/runtime/syscall
+internal/goexperiment
 sync/atomic
+internal/abi
+internal/msan
+internal/goos
 internal/runtime/atomic
-internal/goexperiment
-crypto/internal/fips140/subtle
 internal/runtime/math
-internal/runtime/sys
-internal/abi
-crypto/internal/fips140deps/byteorder
+unicode/utf16
+github.com/google/go-cmp/cmp/internal/flags
+log/internal
+crypto/internal/fips140/alias
+crypto/internal/boring/sig
+container/list
+vendor/golang.org/x/crypto/cryptobyte/asn1
+vendor/golang.org/x/crypto/internal/alias
+internal/nettrace
 internal/chacha8rand
-internal/runtime/exithook
-crypto/internal/fips140deps/cpu
+crypto/internal/fips140deps/byteorder
+internal/runtime/sys
+crypto/internal/fips140/subtle
 internal/bytealg
+crypto/internal/fips140deps/cpu
 math
+internal/runtime/exithook
 internal/stringslite
 internal/race
-internal/sync
 internal/runtime/maps
+internal/sync
 runtime
-crypto/subtle
-weak
-iter
 internal/reflectlite
 sync
-maps
+iter
+crypto/subtle
+weak
 slices
+maps
 errors
 sort
-internal/testlog
+internal/oserror
+path
+math/rand/v2
+vendor/golang.org/x/net/dns/dnsmessage
+strconv
+io
 internal/bisect
+internal/testlog
 internal/singleflight
 unique
+syscall
 runtime/cgo
-internal/oserror
-path
-io
-strconv
-vendor/golang.org/x/net/dns/dnsmessage
-math/rand/v2
-internal/godebug
 bytes
-syscall
-crypto/internal/randutil
 hash
-strings
-hash/crc32
-crypto/internal/fips140deps/godebug
-math/rand
-crypto
+crypto/internal/randutil
 net/netip
+strings
 reflect
-vendor/golang.org/x/text/transform
+internal/godebug
+math/rand
 github.com/kr/text
 go/build/constraint
-net/http/internal/ascii
-crypto/internal/fips140
+regexp/syntax
 bufio
+crypto
+crypto/internal/fips140deps/godebug
 crypto/internal/impl
+net/http/internal/ascii
+vendor/golang.org/x/text/transform
+hash/crc32
 net/http/internal/testcert
-regexp/syntax
-crypto/internal/fips140/sha256
+crypto/internal/fips140
 crypto/internal/fips140/sha3
-crypto/tls/internal/fips140tls
 crypto/internal/fips140/sha512
-crypto/internal/fips140/hmac
+crypto/tls/internal/fips140tls
+crypto/internal/fips140/sha256
+internal/syscall/unix
+internal/syscall/execenv
+time
 crypto/sha3
-crypto/internal/fips140/check
+crypto/internal/fips140/hmac
 crypto/internal/fips140hash
-crypto/internal/fips140/tls12
-crypto/internal/fips140/hkdf
+crypto/internal/fips140/check
+regexp
 crypto/internal/fips140/edwards25519/field
-crypto/internal/fips140/bigmod
 crypto/internal/fips140/aes
+crypto/internal/fips140/hkdf
+crypto/internal/fips140/bigmod
+crypto/internal/fips140/tls12
 crypto/internal/fips140/nistec/fiat
-regexp
 crypto/internal/fips140/tls13
-internal/syscall/execenv
-internal/syscall/unix
-time
 crypto/internal/fips140/edwards25519
-crypto/internal/fips140/nistec
-context
-github.com/google/go-cmp/cmp/internal/diff
 io/fs
+github.com/google/go-cmp/cmp/internal/diff
 internal/poll
+context
+encoding/binary
 internal/fmtsort
 github.com/google/go-cmp/cmp/internal/function
 github.com/rogpeppe/go-internal/fmtsort
-encoding/binary
 internal/filepathlite
 os
 encoding/base64
 vendor/golang.org/x/crypto/internal/poly1305
+crypto/internal/fips140/nistec
 encoding/pem
-internal/sysinfo
-fmt
+io/ioutil
 path/filepath
+fmt
+internal/sysinfo
 crypto/internal/sysrand
-io/ioutil
 vendor/golang.org/x/sys/cpu
-net
 crypto/internal/entropy
 crypto/internal/fips140/drbg
 crypto/internal/fips140only
-crypto/internal/fips140/ecdh
-crypto/internal/fips140/ed25519
-crypto/internal/fips140/ecdsa
+crypto/internal/fips140/aes/gcm
 crypto/internal/fips140/rsa
+crypto/internal/fips140/ed25519
 crypto/internal/fips140/mlkem
-crypto/internal/fips140/aes/gcm
-crypto/rc4
+crypto/internal/fips140/ecdh
+crypto/internal/fips140/ecdsa
+net
 crypto/md5
+crypto/rc4
 crypto/cipher
+github.com/google/go-cmp/cmp/internal/value
 log
-go/token
 text/tabwriter
-encoding/hex
+flag
+encoding/json
+runtime/debug
 runtime/trace
-github.com/google/go-cmp/cmp/internal/value
+encoding/hex
 go/doc/comment
+go/token
 net/url
 gopkg.in/mgo.v2/internal/json
-flag
-net/http/internal
-mime/quotedprintable
-vendor/golang.org/x/net/http2/hpack
-mime
-runtime/debug
-encoding/json
-compress/flate
 gopkg.in/yaml.v3
+compress/flate
+vendor/golang.org/x/net/http2/hpack
 vendor/golang.org/x/text/unicode/norm
 crypto/internal/boring
-vendor/golang.org/x/crypto/chacha20
 math/big
 crypto/des
+github.com/google/go-cmp/cmp
 crypto/aes
-crypto/ecdh
 crypto/sha512
+crypto/ecdh
 crypto/hmac
-crypto/sha256
+vendor/golang.org/x/crypto/chacha20
 crypto/sha1
-vendor/golang.org/x/crypto/chacha20poly1305
-github.com/google/go-cmp/cmp
+crypto/sha256
+mime
 go/scanner
+mime/quotedprintable
 github.com/kr/pretty
 vendor/golang.org/x/text/unicode/bidi
+net/http/internal
 go/ast
-testing
+vendor/golang.org/x/crypto/chacha20poly1305
 compress/gzip
+testing
 vendor/golang.org/x/text/secure/bidirule
 vendor/golang.org/x/net/idna
 go/parser
+crypto/rand
+crypto/elliptic
 go/printer
-github.com/google/go-cmp/cmp/cmpopts
 crypto/internal/boring/bbig
-crypto/rand
-crypto/dsa
 encoding/asn1
-crypto/elliptic
+crypto/dsa
 crypto/ed25519
 crypto/internal/hpke
 crypto/rsa
 gopkg.in/mgo.v2/bson
-crypto/x509/pkix
+github.com/google/go-cmp/cmp/cmpopts
 vendor/golang.org/x/crypto/cryptobyte
-github.com/frankban/quicktest
+crypto/x509/pkix
 crypto/ecdsa
-vendor/golang.org/x/net/http/httpproxy
+github.com/frankban/quicktest
 net/textproto
 crypto/x509
+vendor/golang.org/x/net/http/httpproxy
 vendor/golang.org/x/net/http/httpguts
 mime/multipart
 crypto/tls
@@ -646,7 +682,7 @@
 net/http/httptest
 github.com/juju/qthttptest
    dh_auto_test -O--builddirectory=_build -O--buildsystem=golang
-	cd _build && go test -vet=off -v -p 42 github.com/juju/qthttptest
+	cd _build && go test -vet=off -v -p 20 github.com/juju/qthttptest
 === RUN   TestAssertJSONCall
 === RUN   TestAssertJSONCall/simple_request
     http.go:99: JSON call, url "/"
@@ -674,25 +710,25 @@
     http.go:99: JSON call, url "/"
 === RUN   TestAssertJSONCall/expect_error_regexp
     http.go:99: JSON call, url "/"
---- PASS: TestAssertJSONCall (0.01s)
-    --- PASS: TestAssertJSONCall/simple_request (0.00s)
+--- PASS: TestAssertJSONCall (0.03s)
+    --- PASS: TestAssertJSONCall/simple_request (0.01s)
     --- PASS: TestAssertJSONCall/method_not_specified (0.00s)
     --- PASS: TestAssertJSONCall/POST_request_with_a_body (0.00s)
     --- PASS: TestAssertJSONCall/GET_request_with_custom_headers (0.00s)
-    --- PASS: TestAssertJSONCall/POST_request_with_a_JSON_body (0.00s)
+    --- PASS: TestAssertJSONCall/POST_request_with_a_JSON_body (0.01s)
     --- PASS: TestAssertJSONCall/authentication (0.00s)
     --- PASS: TestAssertJSONCall/test_for_ExceptHeader_in_response (0.00s)
     --- PASS: TestAssertJSONCall/test_case_insensitive_for_ExceptHeader_in_response (0.00s)
-    --- PASS: TestAssertJSONCall/error_status (0.00s)
+    --- PASS: TestAssertJSONCall/error_status (0.01s)
     --- PASS: TestAssertJSONCall/custom_Do (0.00s)
     --- PASS: TestAssertJSONCall/custom_Do_with_seekable_JSON_body (0.00s)
     --- PASS: TestAssertJSONCall/expect_error (0.00s)
     --- PASS: TestAssertJSONCall/expect_error_regexp (0.00s)
 === RUN   TestAssertJSONCallWithBodyAsserter
     http.go:99: JSON call, url "/"
---- PASS: TestAssertJSONCallWithBodyAsserter (0.00s)
+--- PASS: TestAssertJSONCallWithBodyAsserter (0.01s)
 === RUN   TestAssertJSONCallWithHostedURL
-    http.go:99: JSON call, url "http://127.0.0.1:41695/foo"
+    http.go:99: JSON call, url "http://127.0.0.1:40025/foo"
 --- PASS: TestAssertJSONCallWithHostedURL (0.00s)
 === RUN   TestDoRequestWithInferrableContentLength
     http_test.go:306: test 0
@@ -702,7 +738,7 @@
 === RUN   TestTransport
 --- PASS: TestTransport (0.00s)
 PASS
-ok  	github.com/juju/qthttptest	0.022s
+ok  	github.com/juju/qthttptest	0.080s
    create-stamp debian/debhelper-build-stamp
    dh_testroot -O--builddirectory=_build -O--buildsystem=golang
    dh_prep -O--builddirectory=_build -O--buildsystem=golang
@@ -729,12 +765,14 @@
 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/2299167/tmp/hooks/B01_cleanup starting
+I: user script /srv/workspace/pbuilder/2299167/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/1905293 and its subdirectories
-I: Current time: Mon Apr 13 12:02:28 -12 2026
-I: pbuilder-time-stamp: 1776124948
+I: removing directory /srv/workspace/pbuilder/2299167 and its subdirectories
+I: Current time: Wed Mar 12 07:44:49 +14 2025
+I: pbuilder-time-stamp: 1741715089