diff --git a/.github/actions/configure-gentoo/action.yml b/.github/actions/configure-gentoo/action.yml
new file mode 100644
index 0000000000000..e1ae914681fb0
--- /dev/null
+++ b/.github/actions/configure-gentoo/action.yml
@@ -0,0 +1,81 @@
+name: ./configure
+inputs:
+  configurationParameters:
+    default: ''
+    required: false
+  skipSlow:
+    default: false
+    required: false
+runs:
+  using: composite
+  steps:
+    - shell: bash
+      run: |
+        set -x
+        ./buildconf --force
+        ./configure \
+          --enable-option-checking=fatal \
+          --prefix=/usr \
+          --with-libdir=lib64 \
+          --enable-phpdbg \
+          --enable-fpm \
+          --with-pdo-mysql=mysqlnd \
+          --with-mysqli=mysqlnd \
+          ${{ inputs.skipSlow == 'false' && '--with-pgsql' || '' }} \
+          ${{ inputs.skipSlow == 'false' && '--with-pdo-pgsql' || '' }} \
+          ${{ inputs.skipSlow == 'false' && '--with-pdo-sqlite' || '' }} \
+          --enable-intl \
+          --without-pear \
+          --enable-gd \
+          --with-jpeg \
+          --with-webp \
+          --with-freetype \
+          --with-xpm \
+          --enable-exif \
+          --with-zip \
+          --with-zlib \
+          --enable-soap \
+          --enable-xmlreader \
+          --with-xsl \
+          ${{ inputs.skipSlow == 'false' && '--with-tidy' || '' }} \
+          --enable-sysvsem \
+          --enable-sysvshm \
+          --enable-shmop \
+          --enable-pcntl \
+          --with-readline \
+          --enable-mbstring \
+          --with-iconv \
+          --with-curl \
+          --with-gettext \
+          --enable-sockets \
+          --with-bz2 \
+          --with-openssl \
+          --with-gmp \
+          --enable-bcmath \
+          --enable-calendar \
+          --enable-ftp \
+          ${{ inputs.skipSlow == 'false' && '--with-enchant=/usr' || '' }} \
+          --enable-sysvmsg \
+          --with-ffi \
+          --enable-zend-test \
+          ${{ inputs.skipSlow == 'false' && '--enable-dl-test=shared' || '' }} \
+          ${{ inputs.skipSlow == 'false' && '--with-ldap' || '' }} \
+          ${{ inputs.skipSlow == 'false' && '--with-ldap-sasl' || '' }} \
+          --with-password-argon2 \
+          --with-mhash \
+          --with-sodium \
+          --enable-dba \
+          --with-cdb \
+          --enable-flatfile \
+          --enable-inifile \
+          --with-tcadb \
+          --with-lmdb \
+          --with-qdbm \
+          ${{ inputs.skipSlow == 'false' && '--with-snmp' || '' }} \
+          ${{ inputs.skipSlow == 'false' && '--with-unixODBC' || '' }} \
+          ${{ inputs.skipSlow == 'false' && '--with-pdo-odbc=unixODBC,/usr' || '' }} \
+          --with-config-file-path=/etc \
+          --with-config-file-scan-dir=/etc/php.d \
+          ${{ inputs.skipSlow == 'false' && '--with-pdo-dblib' || '' }} \
+          --enable-werror \
+          ${{ inputs.configurationParameters }} || cat config.log
diff --git a/.github/actions/test-gentoo/action.yml b/.github/actions/test-gentoo/action.yml
new file mode 100644
index 0000000000000..ec9fb0b70c6a3
--- /dev/null
+++ b/.github/actions/test-gentoo/action.yml
@@ -0,0 +1,34 @@
+name: Test
+inputs:
+  runTestsParameters:
+    default: ''
+    required: false
+runs:
+  using: composite
+  steps:
+    - shell: bash
+      run: |
+        set -x
+        # XXX: Set up other database tests?
+        # XXX: These tests are not running containerized
+        export MYSQL_TEST_USER=ci
+        export MYSQL_TEST_PASSWD=ci
+        if [[ -z "$PDO_MYSQL_TEST_DSN" ]]; then
+          export PDO_MYSQL_TEST_DSN="mysql:host=localhost;dbname=test"
+        fi
+        export PDO_MYSQL_TEST_USER=ci
+        export PDO_MYSQL_TEST_PASS=ci
+        export PGSQL_TEST_CONNSTR="host=localhost dbname=test port=5432 user=ci password=ci"
+        if [[ -z "$PDO_PGSQL_TEST_DSN" ]]; then
+          export PDO_PGSQL_TEST_DSN="pgsql:host=localhost port=5432 dbname=test user=ci password=ci"
+        fi
+        # Slow tests criteron is doubled because this runner isn't as fast as others
+        export SKIP_IO_CAPTURE_TESTS=1
+        export STACK_LIMIT_DEFAULTS_CHECK=1
+        sapi/cli/php run-tests.php -P -q ${{ inputs.runTestsParameters }} \
+          -j$(nproc) \
+          -g FAIL,BORK,LEAK,XLEAK \
+          --no-progress \
+          --show-diff \
+          --show-slow 2000 \
+          --set-timeout 120
diff --git a/.github/workflows/nightly.yml b/.github/workflows/nightly.yml
index 2377286ca830c..7993c1b6e3586 100644
--- a/.github/workflows/nightly.yml
+++ b/.github/workflows/nightly.yml
@@ -17,6 +17,9 @@ on:
       run_alpine:
         required: true
         type: boolean
+      run_linux_ppc64:
+        required: true
+        type: boolean
       run_macos_arm64:
         required: true
         type: boolean
@@ -35,6 +38,49 @@ on:
 permissions:
   contents: read
 jobs:
+  LINUX_PPC64:
+    if: inputs.run_linux_ppc64
+    name: LINUX_PPC64_ASAN_UBSAN_DEBUG_ZTS
+    # This runs on a self-hosted runner; see https://wiki.php.net/systems/ci
+    runs-on: [self-hosted, gentoo, ppc64]
+    steps:
+      - name: git checkout
+        uses: actions/checkout@v4
+        with:
+          ref: ${{ inputs.branch }}
+      - name: System info
+        run: |
+          echo "::group::Show host CPU info"
+          lscpu
+          echo "::endgroup::"
+          echo "::group::Show installed packages"
+          cat /var/lib/portage/world
+          echo "::endgroup::"
+      - name: ./configure
+        uses: ./.github/actions/configure-gentoo
+        with:
+          configurationParameters: >-
+            CFLAGS="-fsanitize=undefined,address -fno-sanitize=function -DZEND_TRACK_ARENA_ALLOC"
+            LDFLAGS="-fsanitize=undefined,address -fno-sanitize=function"
+            CC=clang-17
+            CXX=clang++-17
+            --enable-debug
+            --enable-zts
+          skipSlow: false # FIXME: This should likely include slow extensions
+      - name: make
+        run: make -j$(/usr/bin/nproc) >/dev/null
+      # Skip an install action for now
+      - name: Tests
+        uses: ./.github/actions/test-gentoo
+        # There is no PPC JIT, so rip this out
+        with:
+          runTestsParameters: >-
+            --asan -x
+      - name: Notify Slack
+        if: failure()
+        uses: ./.github/actions/notify-slack
+        with:
+          token: ${{ secrets.ACTION_MONITORING_SLACK }}
   ALPINE:
     if: inputs.run_alpine
     name: ALPINE_X64_ASAN_UBSAN_DEBUG_ZTS
diff --git a/.github/workflows/root.yml b/.github/workflows/root.yml
index 5cdd70489343f..25b7a6baadef7 100644
--- a/.github/workflows/root.yml
+++ b/.github/workflows/root.yml
@@ -53,6 +53,7 @@ jobs:
       community_verify_type_inference: ${{ (matrix.branch.version[0] == 8 && matrix.branch.version[1] >= 4) || matrix.branch.version[0] >= 9 }}
       libmysqlclient_with_mysqli: ${{ (matrix.branch.version[0] == 8 && matrix.branch.version[1] == 1) }}
       run_alpine: ${{ (matrix.branch.version[0] == 8 && matrix.branch.version[1] >= 4) || matrix.branch.version[0] >= 9 }}
+      run_linux_ppc64: ${{ (matrix.branch.version[0] == 8 && matrix.branch.version[1] >= 4) || matrix.branch.version[0] >= 9 }}
       run_macos_arm64: ${{ (matrix.branch.version[0] == 8 && matrix.branch.version[1] >= 4) || matrix.branch.version[0] >= 9 }}
       ubuntu_version: ${{
         (((matrix.branch.version[0] == 8 && matrix.branch.version[1] >= 5) || matrix.branch.version[0] >= 9) && '24.04')