Added a new workflow step, “Bundle scripting runtimes in AppDir”, that copies Python and Perl runtime artifacts into AppDir (Python binary + stdlib + libpython3*.so*, Perl binary + common Perl library/share paths). This addresses the root issue that runner-installed runtimes were not necessarily ending up inside the final AppImage payload.

Updated AppRun to explicitly set PYTHONHOME to the bundled runtime root and initialize PYTHONPATH from bundled Python directories, so embedded Python can resolve core modules like encodings at runtime.

.github/workflows/appimage-build.yml

@@ -61,6 +61,39 @@ jobs:
           rm -rf AppDir
           DESTDIR="${PWD}/AppDir" ninja -C build install
 
+      - name: Bundle scripting runtimes in AppDir
+        run: |
+          set -eux
+
+          python3_version="$(python3 -c 'import sys; print(f"{sys.version_info.major}.{sys.version_info.minor}")')"
+
+          install -Dm755 "$(command -v python3)" "AppDir/usr/bin/python3"
+          if [ -x "/usr/bin/perl" ]; then
+            install -Dm755 /usr/bin/perl AppDir/usr/bin/perl
+          fi
+
+          install -d AppDir/usr/lib
+          cp -a "/usr/lib/python${python3_version}" "AppDir/usr/lib/"
+
+          if [ -d "/usr/lib/x86_64-linux-gnu/perl" ]; then
+            install -d AppDir/usr/lib/x86_64-linux-gnu
+            cp -a /usr/lib/x86_64-linux-gnu/perl AppDir/usr/lib/x86_64-linux-gnu/
+          fi
+
+          if [ -d "/usr/share/perl" ]; then
+            install -d AppDir/usr/share
+            cp -a /usr/share/perl AppDir/usr/share/
+          fi
+
+          if [ -d "/usr/share/perl5" ]; then
+            install -d AppDir/usr/share
+            cp -a /usr/share/perl5 AppDir/usr/share/
+          fi
+          if compgen -G '/usr/lib/x86_64-linux-gnu/libpython3*.so*' > /dev/null; then
+            install -d AppDir/usr/lib/x86_64-linux-gnu
+            cp -a /usr/lib/x86_64-linux-gnu/libpython3*.so* AppDir/usr/lib/x86_64-linux-gnu/
+          fi
+
       - name: Verify bundled plugins
         run: |
           set -eux
@@ -118,6 +151,14 @@ jobs:
             export GIO_EXTRA_MODULES="$APPDIR/usr/lib/gio/modules${GIO_EXTRA_MODULES:+:$GIO_EXTRA_MODULES}"
           fi
 
+          export PYTHONHOME="$APPDIR/usr"
+          python_stdlib_dir="$(find "$APPDIR/usr/lib" -maxdepth 1 -type d -name 'python3.*' | head -n 1 || true)"
+          if [ -n "$python_stdlib_dir" ] && [ -d "$python_stdlib_dir/dist-packages" ]; then
+            export PYTHONPATH="$python_stdlib_dir/dist-packages:$APPDIR/usr/lib/python3/dist-packages${PYTHONPATH:+:$PYTHONPATH}"
+          else
+            export PYTHONPATH="$APPDIR/usr/lib/python3/dist-packages${PYTHONPATH:+:$PYTHONPATH}"
+          fi
+
           # OpenSSL trust store override
           export SSL_CERT_FILE="${SSL_CERT_FILE:-$APPDIR/etc/ssl/certs/ca-certificates.crt}"
           export SSL_CERT_DIR="${SSL_CERT_DIR:-$APPDIR/etc/ssl/certs}"