diff --git a/.gitlab-ci.d/cirrus/freebsd-12.vars b/.gitlab-ci.d/cirrus/freebsd-12.vars
index 44d8a2a511..0bff53be44 100644
--- a/.gitlab-ci.d/cirrus/freebsd-12.vars
+++ b/.gitlab-ci.d/cirrus/freebsd-12.vars
@@ -14,3 +14,8 @@ PIP3='/usr/local/bin/pip-3.8'
 PKGS='alsa-lib bash bison bzip2 ca_root_nss capstone4 ccache cdrkit-genisoimage cmocka ctags curl cyrus-sasl dbus diffutils dtc flex fusefs-libs3 gettext git glib gmake gnutls gsed gtk3 json-c libepoxy libffi libgcrypt libjpeg-turbo libnfs libslirp libspice-server libssh libtasn1 llvm lzo2 meson ncurses nettle ninja opencv pixman pkgconf png py39-numpy py39-pillow py39-pip py39-sphinx py39-sphinx_rtd_theme py39-yaml python3 rpm2cpio sdl2 sdl2_image snappy sndio socat spice-protocol tesseract usbredir virglrenderer vte3 zstd'
 PYPI_PKGS=''
 PYTHON='/usr/local/bin/python3'
+# As a final step configure the user (if env is defined)
+ARG USER
+ARG UID
+RUN if [ "${USER}" ]; then \
+  id ${USER} 2>/dev/null || useradd -u ${UID} -U ${USER}; fi
\ No newline at end of file
diff --git a/.gitlab-ci.d/cirrus/freebsd-13.vars b/.gitlab-ci.d/cirrus/freebsd-13.vars
index 7622c849b2..235d08a5ee 100644
--- a/.gitlab-ci.d/cirrus/freebsd-13.vars
+++ b/.gitlab-ci.d/cirrus/freebsd-13.vars
@@ -14,3 +14,8 @@ PIP3='/usr/local/bin/pip-3.8'
 PKGS='alsa-lib bash bison bzip2 ca_root_nss capstone4 ccache cdrkit-genisoimage cmocka ctags curl cyrus-sasl dbus diffutils dtc flex fusefs-libs3 gettext git glib gmake gnutls gsed gtk3 json-c libepoxy libffi libgcrypt libjpeg-turbo libnfs libslirp libspice-server libssh libtasn1 llvm lzo2 meson ncurses nettle ninja opencv pixman pkgconf png py39-numpy py39-pillow py39-pip py39-sphinx py39-sphinx_rtd_theme py39-yaml python3 rpm2cpio sdl2 sdl2_image snappy sndio socat spice-protocol tesseract usbredir virglrenderer vte3 zstd'
 PYPI_PKGS=''
 PYTHON='/usr/local/bin/python3'
+# As a final step configure the user (if env is defined)
+ARG USER
+ARG UID
+RUN if [ "${USER}" ]; then \
+  id ${USER} 2>/dev/null || useradd -u ${UID} -U ${USER}; fi
\ No newline at end of file
diff --git a/.gitlab-ci.d/cirrus/macos-12.vars b/.gitlab-ci.d/cirrus/macos-12.vars
index da6aa6469b..599e210707 100644
--- a/.gitlab-ci.d/cirrus/macos-12.vars
+++ b/.gitlab-ci.d/cirrus/macos-12.vars
@@ -14,3 +14,8 @@ PIP3='/opt/homebrew/bin/pip3'
 PKGS='bash bc bison bzip2 capstone ccache cmocka ctags curl dbus diffutils dtc flex gcovr gettext git glib gnu-sed gnutls gtk+3 jemalloc jpeg-turbo json-c libepoxy libffi libgcrypt libiscsi libnfs libpng libslirp libssh libtasn1 libusb llvm lzo make meson ncurses nettle ninja pixman pkg-config python3 rpm2cpio sdl2 sdl2_image snappy socat sparse spice-protocol tesseract usbredir vde vte3 zlib zstd'
 PYPI_PKGS='PyYAML numpy pillow sphinx sphinx-rtd-theme'
 PYTHON='/opt/homebrew/bin/python3'
+# As a final step configure the user (if env is defined)
+ARG USER
+ARG UID
+RUN if [ "${USER}" ]; then \
+  id ${USER} 2>/dev/null || useradd -u ${UID} -U ${USER}; fi
\ No newline at end of file
diff --git a/tests/docker/dockerfiles/alpine.docker b/tests/docker/dockerfiles/alpine.docker
index 56cf14e553..7b82dec8e5 100644
--- a/tests/docker/dockerfiles/alpine.docker
+++ b/tests/docker/dockerfiles/alpine.docker
@@ -124,3 +124,8 @@ ENV LANG "en_US.UTF-8"
 ENV MAKE "/usr/bin/make"
 ENV NINJA "/usr/bin/ninja"
 ENV PYTHON "/usr/bin/python3"
+# As a final step configure the user (if env is defined)
+ARG USER
+ARG UID
+RUN if [ "${USER}" ]; then \
+  id ${USER} 2>/dev/null || useradd -u ${UID} -U ${USER}; fi
\ No newline at end of file
diff --git a/tests/docker/dockerfiles/centos8.docker b/tests/docker/dockerfiles/centos8.docker
index 1291ae1b04..2cca33e730 100644
--- a/tests/docker/dockerfiles/centos8.docker
+++ b/tests/docker/dockerfiles/centos8.docker
@@ -134,3 +134,8 @@ ENV LANG "en_US.UTF-8"
 ENV MAKE "/usr/bin/make"
 ENV NINJA "/usr/bin/ninja"
 ENV PYTHON "/usr/bin/python3"
+# As a final step configure the user (if env is defined)
+ARG USER
+ARG UID
+RUN if [ "${USER}" ]; then \
+  id ${USER} 2>/dev/null || useradd -u ${UID} -U ${USER}; fi
\ No newline at end of file
diff --git a/tests/docker/dockerfiles/debian-amd64-cross.docker b/tests/docker/dockerfiles/debian-amd64-cross.docker
index 856db95100..50a2b34c62 100644
--- a/tests/docker/dockerfiles/debian-amd64-cross.docker
+++ b/tests/docker/dockerfiles/debian-amd64-cross.docker
@@ -169,3 +169,8 @@ ENV ABI "x86_64-linux-gnu"
 ENV MESON_OPTS "--cross-file=x86_64-linux-gnu"
 ENV QEMU_CONFIGURE_OPTS --cross-prefix=x86_64-linux-gnu-
 ENV DEF_TARGET_LIST x86_64-softmmu,x86_64-linux-user,i386-softmmu,i386-linux-user
+# As a final step configure the user (if env is defined)
+ARG USER
+ARG UID
+RUN if [ "${USER}" ]; then \
+  id ${USER} 2>/dev/null || useradd -u ${UID} -U ${USER}; fi
\ No newline at end of file
diff --git a/tests/docker/dockerfiles/debian-amd64.docker b/tests/docker/dockerfiles/debian-amd64.docker
index e3dba71ad5..d77e3d169a 100644
--- a/tests/docker/dockerfiles/debian-amd64.docker
+++ b/tests/docker/dockerfiles/debian-amd64.docker
@@ -155,3 +155,8 @@ RUN git clone https://github.com/luigirizzo/netmap.git /usr/src/netmap
 RUN cd /usr/src/netmap && git checkout v11.3
 RUN cd /usr/src/netmap/LINUX && ./configure --no-drivers --no-apps --kernel-dir=$(ls -d /usr/src/linux-headers-*-amd64) && make install
 ENV QEMU_CONFIGURE_OPTS --enable-netmap
+# As a final step configure the user (if env is defined)
+ARG USER
+ARG UID
+RUN if [ "${USER}" ]; then \
+  id ${USER} 2>/dev/null || useradd -u ${UID} -U ${USER}; fi
\ No newline at end of file
diff --git a/tests/docker/dockerfiles/debian-arm64-cross.docker b/tests/docker/dockerfiles/debian-arm64-cross.docker
index b00e9e9bcf..5288435da1 100644
--- a/tests/docker/dockerfiles/debian-arm64-cross.docker
+++ b/tests/docker/dockerfiles/debian-arm64-cross.docker
@@ -168,3 +168,8 @@ ENV ABI "aarch64-linux-gnu"
 ENV MESON_OPTS "--cross-file=aarch64-linux-gnu"
 ENV QEMU_CONFIGURE_OPTS --cross-prefix=aarch64-linux-gnu-
 ENV DEF_TARGET_LIST aarch64-softmmu,aarch64-linux-user
+# As a final step configure the user (if env is defined)
+ARG USER
+ARG UID
+RUN if [ "${USER}" ]; then \
+  id ${USER} 2>/dev/null || useradd -u ${UID} -U ${USER}; fi
\ No newline at end of file
diff --git a/tests/docker/dockerfiles/debian-armel-cross.docker b/tests/docker/dockerfiles/debian-armel-cross.docker
index fb1129f256..95ce5bbfd0 100644
--- a/tests/docker/dockerfiles/debian-armel-cross.docker
+++ b/tests/docker/dockerfiles/debian-armel-cross.docker
@@ -167,3 +167,8 @@ ENV ABI "arm-linux-gnueabi"
 ENV MESON_OPTS "--cross-file=arm-linux-gnueabi"
 ENV QEMU_CONFIGURE_OPTS --cross-prefix=arm-linux-gnueabi-
 ENV DEF_TARGET_LIST arm-softmmu,arm-linux-user,armeb-linux-user
+# As a final step configure the user (if env is defined)
+ARG USER
+ARG UID
+RUN if [ "${USER}" ]; then \
+  id ${USER} 2>/dev/null || useradd -u ${UID} -U ${USER}; fi
\ No newline at end of file
diff --git a/tests/docker/dockerfiles/debian-armhf-cross.docker b/tests/docker/dockerfiles/debian-armhf-cross.docker
index 7a2b864a38..20f6074d5e 100644
--- a/tests/docker/dockerfiles/debian-armhf-cross.docker
+++ b/tests/docker/dockerfiles/debian-armhf-cross.docker
@@ -168,3 +168,8 @@ ENV ABI "arm-linux-gnueabihf"
 ENV MESON_OPTS "--cross-file=arm-linux-gnueabihf"
 ENV QEMU_CONFIGURE_OPTS --cross-prefix=arm-linux-gnueabihf-
 ENV DEF_TARGET_LIST arm-softmmu,arm-linux-user
+# As a final step configure the user (if env is defined)
+ARG USER
+ARG UID
+RUN if [ "${USER}" ]; then \
+  id ${USER} 2>/dev/null || useradd -u ${UID} -U ${USER}; fi
\ No newline at end of file
diff --git a/tests/docker/dockerfiles/debian-mips64el-cross.docker b/tests/docker/dockerfiles/debian-mips64el-cross.docker
index 5a3340e964..15f8568cb1 100644
--- a/tests/docker/dockerfiles/debian-mips64el-cross.docker
+++ b/tests/docker/dockerfiles/debian-mips64el-cross.docker
@@ -165,3 +165,8 @@ ENV ABI "mips64el-linux-gnuabi64"
 ENV MESON_OPTS "--cross-file=mips64el-linux-gnuabi64"
 ENV QEMU_CONFIGURE_OPTS --cross-prefix=mips64el-linux-gnuabi64-
 ENV DEF_TARGET_LIST mips64el-softmmu,mips64el-linux-user
+# As a final step configure the user (if env is defined)
+ARG USER
+ARG UID
+RUN if [ "${USER}" ]; then \
+  id ${USER} 2>/dev/null || useradd -u ${UID} -U ${USER}; fi
\ No newline at end of file
diff --git a/tests/docker/dockerfiles/debian-mipsel-cross.docker b/tests/docker/dockerfiles/debian-mipsel-cross.docker
index 422fdebe8f..cc6a44dbe7 100644
--- a/tests/docker/dockerfiles/debian-mipsel-cross.docker
+++ b/tests/docker/dockerfiles/debian-mipsel-cross.docker
@@ -165,3 +165,8 @@ ENV ABI "mipsel-linux-gnu"
 ENV MESON_OPTS "--cross-file=mipsel-linux-gnu"
 ENV QEMU_CONFIGURE_OPTS --cross-prefix=mipsel-linux-gnu-
 ENV DEF_TARGET_LIST mipsel-softmmu,mipsel-linux-user
+# As a final step configure the user (if env is defined)
+ARG USER
+ARG UID
+RUN if [ "${USER}" ]; then \
+  id ${USER} 2>/dev/null || useradd -u ${UID} -U ${USER}; fi
\ No newline at end of file
diff --git a/tests/docker/dockerfiles/debian-ppc64el-cross.docker b/tests/docker/dockerfiles/debian-ppc64el-cross.docker
index 78d7ae6211..7ff1e44b88 100644
--- a/tests/docker/dockerfiles/debian-ppc64el-cross.docker
+++ b/tests/docker/dockerfiles/debian-ppc64el-cross.docker
@@ -167,3 +167,8 @@ ENV ABI "powerpc64le-linux-gnu"
 ENV MESON_OPTS "--cross-file=powerpc64le-linux-gnu"
 ENV QEMU_CONFIGURE_OPTS --cross-prefix=powerpc64le-linux-gnu-
 ENV DEF_TARGET_LIST ppc64-softmmu,ppc64-linux-user
+# As a final step configure the user (if env is defined)
+ARG USER
+ARG UID
+RUN if [ "${USER}" ]; then \
+  id ${USER} 2>/dev/null || useradd -u ${UID} -U ${USER}; fi
\ No newline at end of file
diff --git a/tests/docker/dockerfiles/debian-s390x-cross.docker b/tests/docker/dockerfiles/debian-s390x-cross.docker
index d06ea3605a..d084f34cb1 100644
--- a/tests/docker/dockerfiles/debian-s390x-cross.docker
+++ b/tests/docker/dockerfiles/debian-s390x-cross.docker
@@ -166,3 +166,8 @@ ENV ABI "s390x-linux-gnu"
 ENV MESON_OPTS "--cross-file=s390x-linux-gnu"
 ENV QEMU_CONFIGURE_OPTS --cross-prefix=s390x-linux-gnu-
 ENV DEF_TARGET_LIST s390x-softmmu,s390x-linux-user
+# As a final step configure the user (if env is defined)
+ARG USER
+ARG UID
+RUN if [ "${USER}" ]; then \
+  id ${USER} 2>/dev/null || useradd -u ${UID} -U ${USER}; fi
\ No newline at end of file
diff --git a/tests/docker/dockerfiles/fedora-win32-cross.docker b/tests/docker/dockerfiles/fedora-win32-cross.docker
index 21ed1c6081..87d91a6759 100644
--- a/tests/docker/dockerfiles/fedora-win32-cross.docker
+++ b/tests/docker/dockerfiles/fedora-win32-cross.docker
@@ -100,3 +100,8 @@ ENV ABI "i686-w64-mingw32"
 ENV MESON_OPTS "--cross-file=/usr/share/mingw/toolchain-mingw32.meson"
 ENV QEMU_CONFIGURE_OPTS --cross-prefix=i686-w64-mingw32-
 ENV DEF_TARGET_LIST i386-softmmu
+# As a final step configure the user (if env is defined)
+ARG USER
+ARG UID
+RUN if [ "${USER}" ]; then \
+  id ${USER} 2>/dev/null || useradd -u ${UID} -U ${USER}; fi
\ No newline at end of file
diff --git a/tests/docker/dockerfiles/fedora-win64-cross.docker b/tests/docker/dockerfiles/fedora-win64-cross.docker
index 95d30e7936..877766ec6b 100644
--- a/tests/docker/dockerfiles/fedora-win64-cross.docker
+++ b/tests/docker/dockerfiles/fedora-win64-cross.docker
@@ -100,3 +100,8 @@ ENV ABI "x86_64-w64-mingw32"
 ENV MESON_OPTS "--cross-file=/usr/share/mingw/toolchain-mingw64.meson"
 ENV QEMU_CONFIGURE_OPTS --cross-prefix=x86_64-w64-mingw32-
 ENV DEF_TARGET_LIST x86_64-softmmu
+# As a final step configure the user (if env is defined)
+ARG USER
+ARG UID
+RUN if [ "${USER}" ]; then \
+  id ${USER} 2>/dev/null || useradd -u ${UID} -U ${USER}; fi
\ No newline at end of file
diff --git a/tests/docker/dockerfiles/fedora.docker b/tests/docker/dockerfiles/fedora.docker
index 8e06d080b8..4a7a986dfd 100644
--- a/tests/docker/dockerfiles/fedora.docker
+++ b/tests/docker/dockerfiles/fedora.docker
@@ -146,3 +146,8 @@ ENV LANG "en_US.UTF-8"
 ENV MAKE "/usr/bin/make"
 ENV NINJA "/usr/bin/ninja"
 ENV PYTHON "/usr/bin/python3"
+# As a final step configure the user (if env is defined)
+ARG USER
+ARG UID
+RUN if [ "${USER}" ]; then \
+  id ${USER} 2>/dev/null || useradd -u ${UID} -U ${USER}; fi
\ No newline at end of file
diff --git a/tests/docker/dockerfiles/opensuse-leap.docker b/tests/docker/dockerfiles/opensuse-leap.docker
index 568c1c979f..f5f8d4714d 100644
--- a/tests/docker/dockerfiles/opensuse-leap.docker
+++ b/tests/docker/dockerfiles/opensuse-leap.docker
@@ -137,3 +137,8 @@ ENV LANG "en_US.UTF-8"
 ENV MAKE "/usr/bin/make"
 ENV NINJA "/usr/bin/ninja"
 ENV PYTHON "/usr/bin/python3"
+# As a final step configure the user (if env is defined)
+ARG USER
+ARG UID
+RUN if [ "${USER}" ]; then \
+  id ${USER} 2>/dev/null || useradd -u ${UID} -U ${USER}; fi
\ No newline at end of file
diff --git a/tests/docker/dockerfiles/ubuntu2004.docker b/tests/docker/dockerfiles/ubuntu2004.docker
index 75233064de..4d257b922b 100644
--- a/tests/docker/dockerfiles/ubuntu2004.docker
+++ b/tests/docker/dockerfiles/ubuntu2004.docker
@@ -146,3 +146,8 @@ ENV LANG "en_US.UTF-8"
 ENV MAKE "/usr/bin/make"
 ENV NINJA "/usr/bin/ninja"
 ENV PYTHON "/usr/bin/python3"
+# As a final step configure the user (if env is defined)
+ARG USER
+ARG UID
+RUN if [ "${USER}" ]; then \
+  id ${USER} 2>/dev/null || useradd -u ${UID} -U ${USER}; fi
\ No newline at end of file
diff --git a/tests/docker/dockerfiles/ubuntu2204.docker b/tests/docker/dockerfiles/ubuntu2204.docker
index 30b9e56793..41c2d2878e 100644
--- a/tests/docker/dockerfiles/ubuntu2204.docker
+++ b/tests/docker/dockerfiles/ubuntu2204.docker
@@ -145,3 +145,8 @@ ENV LANG "en_US.UTF-8"
 ENV MAKE "/usr/bin/make"
 ENV NINJA "/usr/bin/ninja"
 ENV PYTHON "/usr/bin/python3"
+# As a final step configure the user (if env is defined)
+ARG USER
+ARG UID
+RUN if [ "${USER}" ]; then \
+  id ${USER} 2>/dev/null || useradd -u ${UID} -U ${USER}; fi
\ No newline at end of file
diff --git a/tests/lcitool/refresh b/tests/lcitool/refresh
index cc9e34ac87..88bf33fb74 100755
--- a/tests/lcitool/refresh
+++ b/tests/lcitool/refresh
@@ -40,6 +40,15 @@ def atomic_write(filename, content):
         tmp.unlink()
         raise
 
+# Optional user setting, this will always be the last thing added
+# so maximise the number of layers that are cached
+add_user_mapping = [
+    "# As a final step configure the user (if env is defined)",
+    "ARG USER",
+    "ARG UID",
+    "RUN if [ \"${USER}\" ]; then \\",
+    "  id ${USER} 2>/dev/null || useradd -u ${UID} -U ${USER}; fi"
+]
 
 def generate(filename, cmd, trailer):
     print("Generate %s" % filename)
@@ -51,9 +60,9 @@ def generate(filename, cmd, trailer):
     content = lcitool.stdout.decode("utf8")
     if trailer is not None:
         content += trailer
+    content += "\n".join(add_user_mapping)
     atomic_write(filename, content)
 
-
 def generate_dockerfile(host, target, cross=None, trailer=None):
     filename = Path(src_dir, "tests", "docker", "dockerfiles", host + ".docker")
     cmd = lcitool_cmd + ["dockerfile"]
