diff --git a/Packaging/BuildAppImage.sh b/Packaging/BuildAppImage.sh
index 139a840..48c68ea 100755
--- a/Packaging/BuildAppImage.sh
+++ b/Packaging/BuildAppImage.sh
@@ -1,18 +1,28 @@
 #!/bin/bash
 # Builds dist/SaraSuite-x86_64.AppImage: a PyInstaller one-file build (with
 # the program manifests, fonts and icon bundled) wrapped by appimagetool,
-# the same way SaraFem's AppImage is made. Needs appimagetool on PATH.
+# the same way SaraFem's AppImage is made. Needs podman and appimagetool
+# on PATH.
 set -euo pipefail
 cd "$(dirname "$(readlink -f "$0")")/.."
 
-.venv/bin/pip install --quiet --disable-pip-version-check pyinstaller
 find Programs -name __pycache__ -type d -prune -exec rm -rf {} +
 
-.venv/bin/pyinstaller --noconfirm --clean --log-level WARN \
-    --onefile --windowed --name SaraSuite --collect-data flet \
-    --add-data "$PWD/assets:assets" --add-data "$PWD/Programs:Programs" \
-    --distpath build/PyInstaller/dist --workpath build/PyInstaller/work --specpath build/PyInstaller \
-    "$PWD/Main.py"
+# PyInstaller runs in a manylinux_2_28 container (glibc 2.28) with uv's
+# portable Python, not with Fedora's: PyInstaller bundles libpython, and
+# Fedora's needs a newer glibc than many distros have ("GLIBC_ABI_GNU2_TLS
+# not found"). The Python, venv and downloads are cached in build/Container.
+mkdir -p build/Container
+podman run --rm --security-opt label=disable -v "$PWD:/src" -w /src \
+    -e UV_CACHE_DIR=/src/build/Container/cache -e UV_PYTHON_INSTALL_DIR=/src/build/Container/python \
+    quay.io/pypa/manylinux_2_28_x86_64 bash -euo pipefail -c '
+    uv venv --quiet --allow-existing --managed-python --python 3.14 build/Container/venv
+    uv pip install --quiet --python build/Container/venv -r requirements.txt flet-desktop pyinstaller
+    build/Container/venv/bin/pyinstaller --noconfirm --clean --log-level WARN \
+        --onefile --windowed --name SaraSuite --collect-data flet \
+        --add-data "$PWD/assets:assets" --add-data "$PWD/Programs:Programs" \
+        --distpath build/PyInstaller/dist --workpath build/PyInstaller/work --specpath build/PyInstaller \
+        "$PWD/Main.py"'
 
 AppDir=build/AppDir
 rm -rf "$AppDir"