diff --git a/.github/workflows/coding-standards.yml b/.github/workflows/coding-standards.yml
index 0f70aa565b2e0..c255070266897 100644
--- a/.github/workflows/coding-standards.yml
+++ b/.github/workflows/coding-standards.yml
@@ -45,132 +45,21 @@ concurrency:
 permissions: {}
 
 jobs:
-  # Runs PHP coding standards checks.
-  #
-  # Violations are reported inline with annotations.
-  #
-  # Performs the following steps:
-  # - Checks out the repository.
-  # - Sets up PHP.
-  # - Configures caching for PHPCS scans.
-  # - Installs Composer dependencies.
-  # - Make Composer packages available globally.
-  # - Runs PHPCS on the full codebase with warnings suppressed.
-  # - Generate a report for displaying issues as pull request annotations.
-  # - Runs PHPCS on the `tests` directory without warnings suppressed.
-  # - Generate a report for displaying `test` directory issues as pull request annotations.
-  # - Ensures version-controlled files are not modified or deleted.
+  # Runs the PHP coding standards checks.
   phpcs:
     name: PHP coding standards
-    runs-on: ubuntu-latest
+    uses: WordPress/wordpress-develop/.github/workflows/reusable-coding-standards-php.yml@trunk
     permissions:
       contents: read
-    timeout-minutes: 20
     if: ${{ github.repository == 'WordPress/wordpress-develop' || github.event_name == 'pull_request' }}
 
-    steps:
-      - name: Checkout repository
-        uses: actions/checkout@b4ffde65f46336ab88eb53be808477a3936bae11 # v4.1.1
-        with:
-          show-progress: ${{ runner.debug == '1' && 'true' || 'false' }}
-
-      - name: Set up PHP
-        uses: shivammathur/setup-php@a4e22b60bbb9c1021113f2860347b0759f66fe5d # v2.30.0
-        with:
-          php-version: 'latest'
-          coverage: none
-          tools: cs2pr
-
-      # This date is used to ensure that the PHPCS cache is cleared at least once every week.
-      # http://man7.org/linux/man-pages/man1/date.1.html
-      - name: "Get last Monday's date"
-        id: get-date
-        run: echo "date=$(/bin/date -u --date='last Mon' "+%F")" >> $GITHUB_OUTPUT
-
-      - name: Cache PHPCS scan cache
-        uses: actions/cache@ab5e6d0c87105b4c9c2047343972218f562e4319 # v4.0.1
-        with:
-          path: |
-            .cache/phpcs-src.json
-            .cache/phpcs-tests.json
-          key: ${{ runner.os }}-date-${{ steps.get-date.outputs.date }}-phpcs-cache-${{ hashFiles('**/composer.json', 'phpcs.xml.dist') }}
-
-      # Since Composer dependencies are installed using `composer update` and no lock file is in version control,
-      # passing a custom cache suffix ensures that the cache is flushed at least once per week.
-      - name: Install Composer dependencies
-        uses: ramsey/composer-install@57532f8be5bda426838819c5ee9afb8af389d51a # v3.0.0
-        with:
-          custom-cache-suffix: ${{ steps.get-date.outputs.date }}
-
-      - name: Make Composer packages available globally
-        run: echo "${PWD}/vendor/bin" >> $GITHUB_PATH
-
-      - name: Run PHPCS on all Core files
-        id: phpcs-core
-        run: phpcs -n --report-full --cache=./.cache/phpcs-src.json --report-checkstyle=./.cache/phpcs-report.xml
-
-      - name: Show PHPCS results in PR
-        if: ${{ always() && steps.phpcs-core.outcome == 'failure' }}
-        run: cs2pr ./.cache/phpcs-report.xml
-
-      - name: Check test suite files for warnings
-        id: phpcs-tests
-        run: phpcs tests --report-full --cache=./.cache/phpcs-tests.json --report-checkstyle=./.cache/phpcs-tests-report.xml
-
-      - name: Show test suite scan results in PR
-        if: ${{ always() && steps.phpcs-tests.outcome == 'failure' }}
-        run: cs2pr ./.cache/phpcs-tests-report.xml
-
-      - name: Ensure version-controlled files are not modified during the tests
-        run: git diff --exit-code
-
   # Runs the JavaScript coding standards checks.
-  #
-  # JSHint violations are not currently reported inline with annotations.
-  #
-  # Performs the following steps:
-  # - Checks out the repository.
-  # - Sets up Node.js.
-  # - Logs debug information about the GitHub Action runner.
-  # - Installs npm dependencies.
-  # - Run the WordPress JSHint checks.
-  # - Ensures version-controlled files are not modified or deleted.
   jshint:
     name: JavaScript coding standards
-    runs-on: ubuntu-latest
+    uses: WordPress/wordpress-develop/.github/workflows/reusable-coding-standards-javascript.yml@trunk
     permissions:
       contents: read
-    timeout-minutes: 20
     if: ${{ github.repository == 'WordPress/wordpress-develop' || github.event_name == 'pull_request' }}
-    env:
-      PUPPETEER_SKIP_DOWNLOAD: ${{ true }}
-
-    steps:
-      - name: Checkout repository
-        uses: actions/checkout@b4ffde65f46336ab88eb53be808477a3936bae11 # v4.1.1
-        with:
-          show-progress: ${{ runner.debug == '1' && 'true' || 'false' }}
-
-      - name: Set up Node.js
-        uses: actions/setup-node@60edb5dd545a775178f52524783378180af0d1f8 # v4.0.2
-        with:
-          node-version-file: '.nvmrc'
-          cache: npm
-
-      - name: Log debug information
-        run: |
-          npm --version
-          node --version
-          git --version
-
-      - name: Install npm Dependencies
-        run: npm ci
-
-      - name: Run JSHint
-        run: npm run grunt jshint
-
-      - name: Ensure version-controlled files are not modified or deleted
-        run: git diff --exit-code
 
   slack-notifications:
     name: Slack Notifications
diff --git a/.github/workflows/end-to-end-tests.yml b/.github/workflows/end-to-end-tests.yml
index 757de1f9a42a1..d77e439b2964c 100644
--- a/.github/workflows/end-to-end-tests.yml
+++ b/.github/workflows/end-to-end-tests.yml
@@ -36,105 +36,18 @@ env:
 
 jobs:
   # Runs the end-to-end test suite.
-  #
-  # Performs the following steps:
-  # - Sets environment variables.
-  # - Checks out the repository.
-  # - Sets up Node.js.
-  # - Logs debug information about the GitHub Action runner.
-  # - Installs npm dependencies.
-  # - Install Playwright browsers.
-  # - Builds WordPress to run from the `build` directory.
-  # - Starts the WordPress Docker container.
-  # - Logs the running Docker containers.
-  # - Logs Docker debug information (about both the Docker installation within the runner and the WordPress container).
-  # - Install WordPress within the Docker container.
-  # - Install Gutenberg.
-  # - Run the E2E tests.
-  # - Ensures version-controlled files are not modified or deleted.
   e2e-tests:
-    name: E2E Tests with SCRIPT_DEBUG ${{ matrix.LOCAL_SCRIPT_DEBUG && 'enabled' || 'disabled' }}
-    runs-on: ubuntu-latest
+    name: Test with SCRIPT_DEBUG ${{ matrix.LOCAL_SCRIPT_DEBUG && 'enabled' || 'disabled' }}
+    uses: WordPress/wordpress-develop/.github/workflows/reusable-end-to-end-tests.yml@trunk
     permissions:
       contents: read
-    timeout-minutes: 20
     if: ${{ github.repository == 'WordPress/wordpress-develop' || github.event_name == 'pull_request' }}
     strategy:
       fail-fast: false
       matrix:
         LOCAL_SCRIPT_DEBUG: [ true, false ]
-
-    steps:
-      - name: Configure environment variables
-        run: |
-          echo "PHP_FPM_UID=$(id -u)" >> $GITHUB_ENV
-          echo "PHP_FPM_GID=$(id -g)" >> $GITHUB_ENV
-
-      - name: Checkout repository
-        uses: actions/checkout@b4ffde65f46336ab88eb53be808477a3936bae11 # v4.1.1
-        with:
-          show-progress: ${{ runner.debug == '1' && 'true' || 'false' }}
-
-      - name: Set up Node.js
-        uses: actions/setup-node@60edb5dd545a775178f52524783378180af0d1f8 # v4.0.2
-        with:
-          node-version-file: '.nvmrc'
-          cache: npm
-
-      - name: Log debug information
-        run: |
-          npm --version
-          node --version
-          curl --version
-          git --version
-          locale -a
-
-      - name: Install npm Dependencies
-        run: npm ci
-
-      - name: Install Playwright browsers
-        run: npx playwright install --with-deps
-
-      - name: Build WordPress
-        run: npm run build
-
-      - name: Start Docker environment
-        run: |
-          npm run env:start
-
-      - name: Log running Docker containers
-        run: docker ps -a
-
-      - name: Docker debug information
-        run: |
-          docker -v
-          docker compose run --rm mysql mysql --version
-          docker compose run --rm php php --version
-          docker compose run --rm php php -m
-          docker compose run --rm php php -i
-          docker compose run --rm php locale -a
-
-      - name: Install WordPress
-        env:
-          LOCAL_SCRIPT_DEBUG: ${{ matrix.LOCAL_SCRIPT_DEBUG }}
-        run: npm run env:install
-
-      - name: Install Gutenberg
-        run: npm run env:cli -- plugin install gutenberg --path=/var/www/${{ env.LOCAL_DIR }}
-
-      - name: Run E2E tests
-        run: npm run test:e2e
-
-      - name: Archive debug artifacts (screenshots, HTML snapshots)
-        uses: actions/upload-artifact@5d5d22a31266ced268874388b861e4b58bb5c2f3 # v4.3.1
-        if: always()
-        with:
-            name: failures-artifacts${{ matrix.LOCAL_SCRIPT_DEBUG && '-SCRIPT_DEBUG' || '' }}-${{ github.run_id }}
-            path: artifacts
-            if-no-files-found: ignore
-
-      - name: Ensure version-controlled files are not modified or deleted
-        run: git diff --exit-code
+    with:
+      LOCAL_SCRIPT_DEBUG: ${{ matrix.LOCAL_SCRIPT_DEBUG }}
 
   slack-notifications:
     name: Slack Notifications
diff --git a/.github/workflows/javascript-tests.yml b/.github/workflows/javascript-tests.yml
index b301866834eff..6eec2ac604fb4 100644
--- a/.github/workflows/javascript-tests.yml
+++ b/.github/workflows/javascript-tests.yml
@@ -43,50 +43,14 @@ concurrency:
 permissions: {}
 
 jobs:
-  # Runs the QUnit tests for WordPress.
-  #
-  # Performs the following steps:
-  # - Checks out the repository.
-  # - Sets up Node.js.
-  # - Logs debug information about the GitHub Action runner.
-  # - Installs npm dependencies.
-  # - Run the WordPress QUnit tests.
-  # - Ensures version-controlled files are not modified or deleted.
+  # Runs the WordPress Core JavaScript tests.
   test-js:
     name: QUnit Tests
-    runs-on: ubuntu-latest
+    uses: WordPress/wordpress-develop/.github/workflows/reusable-javascript-tests.yml@trunk
     permissions:
       contents: read
-    timeout-minutes: 20
     if: ${{ github.repository == 'WordPress/wordpress-develop' || github.event_name == 'pull_request' }}
 
-    steps:
-      - name: Checkout repository
-        uses: actions/checkout@b4ffde65f46336ab88eb53be808477a3936bae11 # v4.1.1
-        with:
-          show-progress: ${{ runner.debug == '1' && 'true' || 'false' }}
-
-      - name: Set up Node.js
-        uses: actions/setup-node@60edb5dd545a775178f52524783378180af0d1f8 # v4.0.2
-        with:
-          node-version-file: '.nvmrc'
-          cache: npm
-
-      - name: Log debug information
-        run: |
-          npm --version
-          node --version
-          git --version
-
-      - name: Install npm Dependencies
-        run: npm ci
-
-      - name: Run QUnit tests
-        run: npm run grunt qunit:compiled
-
-      - name: Ensure version-controlled files are not modified or deleted
-        run: git diff --exit-code
-
   slack-notifications:
     name: Slack Notifications
     uses: WordPress/wordpress-develop/.github/workflows/slack-notifications.yml@trunk
diff --git a/.github/workflows/performance.yml b/.github/workflows/performance.yml
index d79ae5f8012e7..dcd6010ad2c97 100644
--- a/.github/workflows/performance.yml
+++ b/.github/workflows/performance.yml
@@ -29,73 +29,11 @@ concurrency:
 # Any needed permissions should be configured at the job level.
 permissions: {}
 
-env:
-  PUPPETEER_SKIP_DOWNLOAD: ${{ true }}
-
-  # Performance testing should be performed in an environment reflecting a standard production environment.
-  LOCAL_WP_DEBUG: false
-  LOCAL_SCRIPT_DEBUG: false
-  LOCAL_SAVEQUERIES: false
-  LOCAL_WP_DEVELOPMENT_MODE: "''"
-
-  # This workflow takes two sets of measurements — one for the current commit,
-  # and another against a consistent version that is used as a baseline measurement.
-  # This is done to isolate variance in measurements caused by the GitHub runners
-  # from differences caused by code changes between commits. The BASE_TAG value here
-  # represents the version being used for baseline measurements. It should only be
-  # changed if we want to normalize results against a different baseline.
-  BASE_TAG: '6.1.1'
-  LOCAL_DIR: build
-  TARGET_REF: ${{ github.event_name == 'pull_request' && github.event.pull_request.base.ref || '' }}
-  TARGET_SHA: ${{ github.event_name == 'pull_request' && github.event.pull_request.base.sha || github.event.before }}
-
 jobs:
   # Runs the performance test suite.
-  #
-  # Performs the following steps:
-  # - Configure environment variables.
-  # - Checkout repository.
-  # - Set up Node.js.
-  # - Log debug information.
-  # - Install npm dependencies.
-  # - Install Playwright browsers.
-  # - Build WordPress.
-  # - Start Docker environment.
-  # - Log running Docker containers.
-  # - Docker debug information.
-  # - Install WordPress.
-  # - Install WordPress Importer plugin.
-  # - Import mock data.
-  # - Deactivate WordPress Importer plugin.
-  # - Update permalink structure.
-  # - Install additional languages.
-  # - Disable external HTTP requests.
-  # - Disable cron.
-  # - List defined constants.
-  # - Install MU plugin.
-  # - Run performance tests (current commit).
-  # - Download previous build artifact (target branch or previous commit).
-  # - Download artifact.
-  # - Unzip the build.
-  # - Run any database upgrades.
-  # - Flush cache.
-  # - Delete expired transients.
-  # - Run performance tests (previous/target commit).
-  # - Set the environment to the baseline version.
-  # - Run any database upgrades.
-  # - Flush cache.
-  # - Delete expired transients.
-  # - Run baseline performance tests.
-  # - Archive artifacts.
-  # - Compare results.
-  # - Add workflow summary.
-  # - Set the base sha.
-  # - Set commit details.
-  # - Publish performance results.
-  # - Ensure version-controlled files are not modified or deleted.
   performance:
-    name: Run performance tests ${{ matrix.memcached && '(with memcached)' || '' }}
-    runs-on: ubuntu-latest
+    name: Performance tests ${{ matrix.memcached && '(with memcached)' || '' }}
+    uses: WordPress/wordpress-develop/.github/workflows/reusable-performance.yml@trunk
     permissions:
       contents: read
     if: ${{ ( github.repository == 'WordPress/wordpress-develop' || github.event_name == 'pull_request' ) && ! contains( github.event.before, '00000000' ) }}
@@ -103,230 +41,8 @@ jobs:
       fail-fast: false
       matrix:
         memcached: [ true, false ]
-    env:
-      LOCAL_PHP_MEMCACHED: ${{ matrix.memcached }}
-    steps:
-      - name: Configure environment variables
-        run: |
-          echo "PHP_FPM_UID=$(id -u)" >> $GITHUB_ENV
-          echo "PHP_FPM_GID=$(id -g)" >> $GITHUB_ENV
-
-      - name: Checkout repository
-        uses: actions/checkout@b4ffde65f46336ab88eb53be808477a3936bae11 # v4.1.1
-        with:
-          show-progress: ${{ runner.debug == '1' && 'true' || 'false' }}
-
-      - name: Set up Node.js
-        uses: actions/setup-node@60edb5dd545a775178f52524783378180af0d1f8 # v4.0.2
-        with:
-          node-version-file: '.nvmrc'
-          cache: npm
-
-      - name: Log debug information
-        run: |
-          npm --version
-          node --version
-          curl --version
-          git --version
-          locale -a
-
-      - name: Install npm dependencies
-        run: npm ci
-
-      - name: Install Playwright browsers
-        run: npx playwright install --with-deps chromium
-
-      - name: Build WordPress
-        run: npm run build
-
-      - name: Start Docker environment
-        run: npm run env:start
-
-      - name: Install object cache drop-in
-        if: ${{ matrix.memcached }}
-        run: cp src/wp-content/object-cache.php build/wp-content/object-cache.php
-
-      - name: Log running Docker containers
-        run: docker ps -a
-
-      - name: Docker debug information
-        run: |
-          docker -v
-          docker compose run --rm mysql mysql --version
-          docker compose run --rm php php --version
-          docker compose run --rm php php -m
-          docker compose run --rm php php -i
-          docker compose run --rm php locale -a
-
-      - name: Install WordPress
-        run: npm run env:install
-
-      - name: Install WordPress Importer plugin
-        run: npm run env:cli -- plugin install wordpress-importer --activate --path=/var/www/${{ env.LOCAL_DIR }}
-
-      - name: Import mock data
-        run: |
-          curl -O https://raw.githubusercontent.com/WordPress/theme-test-data/b9752e0533a5acbb876951a8cbb5bcc69a56474c/themeunittestdata.wordpress.xml
-          npm run env:cli -- import themeunittestdata.wordpress.xml --authors=create --path=/var/www/${{ env.LOCAL_DIR }}
-          rm themeunittestdata.wordpress.xml
-
-      - name: Deactivate WordPress Importer plugin
-        run: npm run env:cli -- plugin deactivate wordpress-importer --path=/var/www/${{ env.LOCAL_DIR }}
-
-      - name: Update permalink structure
-        run: npm run env:cli -- rewrite structure '/%year%/%monthnum%/%postname%/' --path=/var/www/${{ env.LOCAL_DIR }}
-
-      - name: Install additional languages
-        run: |
-          npm run env:cli -- language core install de_DE --path=/var/www/${{ env.LOCAL_DIR }}
-          npm run env:cli -- language plugin install de_DE --all --path=/var/www/${{ env.LOCAL_DIR }}
-          npm run env:cli -- language theme install de_DE --all --path=/var/www/${{ env.LOCAL_DIR }}
-
-      # Prevent background update checks from impacting test stability.
-      - name: Disable external HTTP requests
-        run: npm run env:cli -- config set WP_HTTP_BLOCK_EXTERNAL true --raw --type=constant --path=/var/www/${{ env.LOCAL_DIR }}
-
-      # Prevent background tasks from impacting test stability.
-      - name: Disable cron
-        run: npm run env:cli -- config set DISABLE_WP_CRON true --raw --type=constant --path=/var/www/${{ env.LOCAL_DIR }}
-
-      - name: List defined constants
-        run: npm run env:cli -- config list --path=/var/www/${{ env.LOCAL_DIR }}
-
-      - name: Install MU plugin
-        run: |
-          mkdir ./${{ env.LOCAL_DIR }}/wp-content/mu-plugins
-          cp ./tests/performance/wp-content/mu-plugins/server-timing.php ./${{ env.LOCAL_DIR }}/wp-content/mu-plugins/server-timing.php
-
-      - name: Run performance tests (current commit)
-        run: npm run test:performance
-
-      - name: Download previous build artifact (target branch or previous commit)
-        uses: actions/github-script@60a0d83039c74a4aee543508d2ffcb1c3799cdea # v7.0.1
-        id: get-previous-build
-        with:
-          script: |
-            const artifacts = await github.rest.actions.listArtifactsForRepo({
-              owner: context.repo.owner,
-              repo: context.repo.repo,
-              name: 'wordpress-build-' + process.env.TARGET_SHA,
-            });
-
-            const matchArtifact = artifacts.data.artifacts[0];
-
-            if ( ! matchArtifact ) {
-              core.setFailed( 'No artifact found!' );
-              return false;
-            }
-
-            const download = await github.rest.actions.downloadArtifact( {
-              owner: context.repo.owner,
-              repo: context.repo.repo,
-              artifact_id: matchArtifact.id,
-              archive_format: 'zip',
-            } );
-
-            const fs = require( 'fs' );
-            fs.writeFileSync( '${{ github.workspace }}/before.zip', Buffer.from( download.data ) )
-
-            return true;
-
-      - name: Unzip the build
-        if: ${{ steps.get-previous-build.outputs.result }}
-        run: |
-          unzip ${{ github.workspace }}/before.zip
-          unzip -o ${{ github.workspace }}/wordpress.zip
-
-      - name: Run any database upgrades
-        if: ${{ steps.get-previous-build.outputs.result }}
-        run: npm run env:cli -- core update-db --path=/var/www/${{ env.LOCAL_DIR }}
-
-      - name: Flush cache
-        if: ${{ steps.get-previous-build.outputs.result }}
-        run: npm run env:cli -- cache flush --path=/var/www/${{ env.LOCAL_DIR }}
-
-      - name: Delete expired transients
-        if: ${{ steps.get-previous-build.outputs.result }}
-        run: npm run env:cli -- transient delete --expired --path=/var/www/${{ env.LOCAL_DIR }}
-
-      - name: Run target performance tests (previous/target commit)
-        if: ${{ steps.get-previous-build.outputs.result }}
-        env:
-          TEST_RESULTS_PREFIX: before
-        run: npm run test:performance
-
-      - name: Set the environment to the baseline version
-        if: ${{ github.event_name == 'push' && github.ref == 'refs/heads/trunk' }}
-        run: |
-          npm run env:cli -- core update --version=${{ env.BASE_TAG }} --force --path=/var/www/${{ env.LOCAL_DIR }}
-          npm run env:cli -- core version --path=/var/www/${{ env.LOCAL_DIR }}
-
-      - name: Run any database upgrades
-        if: ${{ github.event_name == 'push' && github.ref == 'refs/heads/trunk' }}
-        run: npm run env:cli -- core update-db --path=/var/www/${{ env.LOCAL_DIR }}
-
-      - name: Flush cache
-        if: ${{ github.event_name == 'push' && github.ref == 'refs/heads/trunk' }}
-        run: npm run env:cli -- cache flush --path=/var/www/${{ env.LOCAL_DIR }}
-
-      - name: Delete expired transients
-        if: ${{ github.event_name == 'push' && github.ref == 'refs/heads/trunk' }}
-        run: npm run env:cli -- transient delete --expired --path=/var/www/${{ env.LOCAL_DIR }}
-
-      - name: Run baseline performance tests
-        if: ${{ github.event_name == 'push' && github.ref == 'refs/heads/trunk' }}
-        env:
-          TEST_RESULTS_PREFIX: base
-        run: npm run test:performance
-
-      - name: Archive artifacts
-        uses: actions/upload-artifact@5d5d22a31266ced268874388b861e4b58bb5c2f3 # v4.3.1
-        if: always()
-        with:
-          name: performance-artifacts${{ matrix.memcached && '-memcached' || '' }}-${{ github.run_id }}
-          path: artifacts
-          if-no-files-found: ignore
-
-      - name: Compare results
-        run: node ./tests/performance/compare-results.js ${{ runner.temp }}/summary.md
-
-      - name: Add workflow summary
-        run: cat ${{ runner.temp }}/summary.md >> $GITHUB_STEP_SUMMARY
-
-      - name: Set the base sha
-        # Only needed when publishing results.
-        if: ${{ github.event_name == 'push' && github.ref == 'refs/heads/trunk' && ! matrix.memcached }}
-        uses: actions/github-script@60a0d83039c74a4aee543508d2ffcb1c3799cdea # v7.0.1
-        id: base-sha
-        with:
-            github-token: ${{ secrets.GITHUB_TOKEN }}
-            script: |
-                const baseRef = await github.rest.git.getRef({ owner: context.repo.owner, repo: context.repo.repo, ref: 'tags/${{ env.BASE_TAG }}' });
-                return baseRef.data.object.sha;
-
-      - name: Set commit details
-        # Only needed when publishing results.
-        if: ${{ github.event_name == 'push' && github.ref == 'refs/heads/trunk' && ! matrix.memcached }}
-        uses: actions/github-script@60a0d83039c74a4aee543508d2ffcb1c3799cdea # v7.0.1
-        id: commit-timestamp
-        with:
-            github-token: ${{ secrets.GITHUB_TOKEN }}
-            script: |
-                const commit_details = await github.rest.git.getCommit({ owner: context.repo.owner, repo: context.repo.repo, commit_sha: context.sha });
-                return parseInt((new Date( commit_details.data.author.date ).getTime() / 1000).toFixed(0))
-
-      - name: Publish performance results
-        # Only publish results on pushes to trunk.
-        if: ${{ github.event_name == 'push' && github.ref == 'refs/heads/trunk' && ! matrix.memcached }}
-        env:
-            BASE_SHA: ${{ steps.base-sha.outputs.result }}
-            COMMITTED_AT: ${{ steps.commit-timestamp.outputs.result }}
-            CODEVITALS_PROJECT_TOKEN: ${{ secrets.CODEVITALS_PROJECT_TOKEN }}
-            HOST_NAME: "www.codevitals.run"
-        run: node ./tests/performance/log-results.js $CODEVITALS_PROJECT_TOKEN trunk $GITHUB_SHA $BASE_SHA $COMMITTED_AT $HOST_NAME
-
-      - name: Ensure version-controlled files are not modified or deleted
-        run: git diff --exit-code
+    with:
+      memcached: ${{ matrix.memcached }}
 
   slack-notifications:
     name: Slack Notifications
diff --git a/.github/workflows/php-compatibility.yml b/.github/workflows/php-compatibility.yml
index bc3363aee8f59..d84a372da8f29 100644
--- a/.github/workflows/php-compatibility.yml
+++ b/.github/workflows/php-compatibility.yml
@@ -40,79 +40,14 @@ concurrency:
 permissions: {}
 
 jobs:
-
   # Runs PHP compatibility testing.
-  #
-  # Violations are reported inline with annotations.
-  #
-  # Performs the following steps:
-  # - Checks out the repository.
-  # - Sets up PHP.
-  # - Logs debug information.
-  # - Configures caching for PHP compatibility scans.
-  # - Installs Composer dependencies.
-  # - Make Composer packages available globally.
-  # - Runs the PHP compatibility tests.
-  # - Generate a report for displaying issues as pull request annotations.
-  # - Ensures version-controlled files are not modified or deleted.
   php-compatibility:
     name: Check PHP compatibility
-    runs-on: ubuntu-latest
+    uses: WordPress/wordpress-develop/.github/workflows/reusable-php-compatibility.yml@trunk
     permissions:
       contents: read
-    timeout-minutes: 20
     if: ${{ github.repository == 'WordPress/wordpress-develop' || github.event_name == 'pull_request' }}
 
-    steps:
-      - name: Checkout repository
-        uses: actions/checkout@b4ffde65f46336ab88eb53be808477a3936bae11 # v4.1.1
-        with:
-          show-progress: ${{ runner.debug == '1' && 'true' || 'false' }}
-
-      - name: Set up PHP
-        uses: shivammathur/setup-php@a4e22b60bbb9c1021113f2860347b0759f66fe5d # v2.30.0
-        with:
-          php-version: '7.4'
-          coverage: none
-          tools: cs2pr
-
-      - name: Log debug information
-        run: |
-          composer --version
-
-      # This date is used to ensure that the PHP compatibility cache is cleared at least once every week.
-      # http://man7.org/linux/man-pages/man1/date.1.html
-      - name: "Get last Monday's date"
-        id: get-date
-        run: echo "date=$(/bin/date -u --date='last Mon' "+%F")" >> $GITHUB_OUTPUT
-
-      - name: Cache PHP compatibility scan cache
-        uses: actions/cache@ab5e6d0c87105b4c9c2047343972218f562e4319 # v4.0.1
-        with:
-          path: .cache/phpcompat.json
-          key: ${{ runner.os }}-date-${{ steps.get-date.outputs.date }}-phpcompat-cache-${{ hashFiles('**/composer.json', 'phpcompat.xml.dist') }}
-
-      # Since Composer dependencies are installed using `composer update` and no lock file is in version control,
-      # passing a custom cache suffix ensures that the cache is flushed at least once per week.
-      - name: Install Composer dependencies
-        uses: ramsey/composer-install@57532f8be5bda426838819c5ee9afb8af389d51a # v3.0.0
-        with:
-          custom-cache-suffix: ${{ steps.get-date.outputs.date }}
-
-      - name: Make Composer packages available globally
-        run: echo "${PWD}/vendor/bin" >> $GITHUB_PATH
-
-      - name: Run PHP compatibility tests
-        id: phpcs
-        run: phpcs --standard=phpcompat.xml.dist --report-full --report-checkstyle=./.cache/phpcs-compat-report.xml
-
-      - name: Show PHPCompatibility results in PR
-        if: ${{ always() && steps.phpcs.outcome == 'failure' }}
-        run: cs2pr ./.cache/phpcs-compat-report.xml
-
-      - name: Ensure version-controlled files are not modified or deleted
-        run: git diff --exit-code
-
   slack-notifications:
     name: Slack Notifications
     uses: WordPress/wordpress-develop/.github/workflows/slack-notifications.yml@trunk
diff --git a/.github/workflows/phpunit-tests.yml b/.github/workflows/phpunit-tests.yml
index 3bc72f8e8c528..b40237f82802d 100644
--- a/.github/workflows/phpunit-tests.yml
+++ b/.github/workflows/phpunit-tests.yml
@@ -36,7 +36,7 @@ jobs:
   #
   test-with-mysql:
     name: PHP ${{ matrix.php }}
-    uses: WordPress/wordpress-develop/.github/workflows/phpunit-tests-run.yml@trunk
+    uses: WordPress/wordpress-develop/.github/workflows/reusable-phpunit-tests.yml@trunk
     permissions:
       contents: read
     secrets: inherit
@@ -108,7 +108,7 @@ jobs:
   #
   test-with-mariadb:
     name: PHP ${{ matrix.php }}
-    uses: WordPress/wordpress-develop/.github/workflows/phpunit-tests-run.yml@trunk
+    uses: WordPress/wordpress-develop/.github/workflows/reusable-phpunit-tests.yml@trunk
     permissions:
       contents: read
     secrets: inherit
diff --git a/.github/workflows/reusable-coding-standards-javascript.yml b/.github/workflows/reusable-coding-standards-javascript.yml
new file mode 100644
index 0000000000000..a424f80630887
--- /dev/null
+++ b/.github/workflows/reusable-coding-standards-javascript.yml
@@ -0,0 +1,56 @@
+##
+# A reusable workflow that checks the JavaScript coding standards.
+##
+name: JavaScript coding standards
+
+on:
+  workflow_call:
+
+env:
+  PUPPETEER_SKIP_DOWNLOAD: ${{ true }}
+
+jobs:
+  # Runs the JavaScript coding standards checks.
+  #
+  # JSHint violations are not currently reported inline with annotations.
+  #
+  # Performs the following steps:
+  # - Checks out the repository.
+  # - Sets up Node.js.
+  # - Logs debug information about the GitHub Action runner.
+  # - Installs npm dependencies.
+  # - Run the WordPress JSHint checks.
+  # - Ensures version-controlled files are not modified or deleted.
+  jshint:
+    name: Run coding standards checks
+    runs-on: ubuntu-latest
+    permissions:
+      contents: read
+    timeout-minutes: 20
+
+    steps:
+      - name: Checkout repository
+        uses: actions/checkout@b4ffde65f46336ab88eb53be808477a3936bae11 # v4.1.1
+        with:
+          show-progress: ${{ runner.debug == '1' && 'true' || 'false' }}
+
+      - name: Set up Node.js
+        uses: actions/setup-node@60edb5dd545a775178f52524783378180af0d1f8 # v4.0.2
+        with:
+          node-version-file: '.nvmrc'
+          cache: npm
+
+      - name: Log debug information
+        run: |
+          npm --version
+          node --version
+          git --version
+
+      - name: Install npm Dependencies
+        run: npm ci
+
+      - name: Run JSHint
+        run: npm run grunt jshint
+
+      - name: Ensure version-controlled files are not modified or deleted
+        run: git diff --exit-code
diff --git a/.github/workflows/reusable-coding-standards-php.yml b/.github/workflows/reusable-coding-standards-php.yml
new file mode 100644
index 0000000000000..3f8520c2f74d7
--- /dev/null
+++ b/.github/workflows/reusable-coding-standards-php.yml
@@ -0,0 +1,92 @@
+##
+# A reusable workflow that checks the PHP coding standards.
+##
+name: PHP coding standards
+
+on:
+  workflow_call:
+    inputs:
+      php-version:
+        description: 'The PHP version to use.'
+        required: false
+        type: 'string'
+        default: 'latest'
+
+jobs:
+  # Runs the PHP coding standards checks.
+  #
+  # Violations are reported inline with annotations.
+  #
+  # Performs the following steps:
+  # - Checks out the repository.
+  # - Sets up PHP.
+  # - Configures caching for PHPCS scans.
+  # - Installs Composer dependencies.
+  # - Make Composer packages available globally.
+  # - Runs PHPCS on the full codebase (warnings excluded).
+  # - Generate a report for displaying issues as pull request annotations.
+  # - Runs PHPCS on the `tests` directory without (warnings included).
+  # - Generate a report for displaying `test` directory issues as pull request annotations.
+  # - Ensures version-controlled files are not modified or deleted.
+  phpcs:
+    name: Run coding standards checks
+    runs-on: ubuntu-latest
+    permissions:
+      contents: read
+    timeout-minutes: 20
+
+    steps:
+      - name: Checkout repository
+        uses: actions/checkout@b4ffde65f46336ab88eb53be808477a3936bae11 # v4.1.1
+        with:
+          show-progress: ${{ runner.debug == '1' && 'true' || 'false' }}
+
+      - name: Set up PHP
+        uses: shivammathur/setup-php@a4e22b60bbb9c1021113f2860347b0759f66fe5d # v2.30.0
+        with:
+          php-version: ${{ inputs.php-version }}
+          coverage: none
+          tools: cs2pr
+
+      # This date is used to ensure that the PHPCS cache is cleared at least once every week.
+      # http://man7.org/linux/man-pages/man1/date.1.html
+      - name: "Get last Monday's date"
+        id: get-date
+        run: echo "date=$(/bin/date -u --date='last Mon' "+%F")" >> $GITHUB_OUTPUT
+
+      - name: Cache PHPCS scan cache
+        uses: actions/cache@ab5e6d0c87105b4c9c2047343972218f562e4319 # v4.0.1
+        with:
+          path: |
+            .cache/phpcs-src.json
+            .cache/phpcs-tests.json
+          key: ${{ runner.os }}-date-${{ steps.get-date.outputs.date }}-php-${{ inputs.php-version }}-phpcs-cache-${{ hashFiles('**/composer.json', 'phpcs.xml.dist') }}
+
+      # Since Composer dependencies are installed using `composer update` and no lock file is in version control,
+      # passing a custom cache suffix ensures that the cache is flushed at least once per week.
+      - name: Install Composer dependencies
+        uses: ramsey/composer-install@57532f8be5bda426838819c5ee9afb8af389d51a # v3.0.0
+        with:
+          custom-cache-suffix: ${{ steps.get-date.outputs.date }}
+
+      - name: Make Composer packages available globally
+        run: echo "${PWD}/vendor/bin" >> $GITHUB_PATH
+
+      - name: Run PHPCS on all Core files
+        id: phpcs-core
+        run: phpcs -n --report-full --cache=./.cache/phpcs-src.json --report-checkstyle=./.cache/phpcs-report.xml
+
+      - name: Show PHPCS results in PR
+        if: ${{ always() && steps.phpcs-core.outcome == 'failure' }}
+        run: cs2pr ./.cache/phpcs-report.xml
+
+      - name: Check test suite files for warnings
+        id: phpcs-tests
+        run: phpcs tests --report-full --cache=./.cache/phpcs-tests.json --report-checkstyle=./.cache/phpcs-tests-report.xml
+
+      - name: Show test suite scan results in PR
+        if: ${{ always() && steps.phpcs-tests.outcome == 'failure' }}
+        run: cs2pr ./.cache/phpcs-tests-report.xml
+
+      - name: Ensure version-controlled files are not modified during the tests
+        run: git diff --exit-code
diff --git a/.github/workflows/reusable-end-to-end-tests.yml b/.github/workflows/reusable-end-to-end-tests.yml
new file mode 100644
index 0000000000000..70609e8a65359
--- /dev/null
+++ b/.github/workflows/reusable-end-to-end-tests.yml
@@ -0,0 +1,123 @@
+##
+# A reusable workflow that runs end-to-end tests.
+#
+# Branches 6.3 and earlier used Puppeteer instead of Playwright.
+# Use https://github.com/WordPress/wordpress-develop/tree/6.3/.github/workflows/reusable-end-to-end-tests.yml instead.
+##
+name: End-to-end Tests
+
+on:
+  workflow_call:
+    inputs:
+      LOCAL_SCRIPT_DEBUG:
+        description: 'Whether to enable script debugging.'
+        required: false
+        type: 'boolean'
+        default: false
+      install-gutenberg:
+        description: 'Whether to install the Gutenberg plugin.'
+        required: false
+        type: 'boolean'
+        default: true
+
+env:
+  LOCAL_DIR: build
+
+jobs:
+  # Runs the end-to-end test suite.
+  #
+  # Performs the following steps:
+  # - Sets environment variables.
+  # - Checks out the repository.
+  # - Sets up Node.js.
+  # - Logs debug information about the GitHub Action runner.
+  # - Installs npm dependencies.
+  # - Install Playwright browsers.
+  # - Builds WordPress to run from the `build` directory.
+  # - Starts the WordPress Docker container.
+  # - Logs the running Docker containers.
+  # - Logs Docker debug information (about both the Docker installation within the runner and the WordPress container).
+  # - Install WordPress within the Docker container.
+  # - Install Gutenberg.
+  # - Run the E2E tests.
+  # - Uploads screenshots and HTML snapshots as an artifact.
+  # - Ensures version-controlled files are not modified or deleted.
+  e2e-tests:
+    name: Run E2E tests
+    runs-on: ubuntu-latest
+    permissions:
+      contents: read
+    timeout-minutes: 20
+
+    steps:
+      - name: Configure environment variables
+        run: |
+          echo "PHP_FPM_UID=$(id -u)" >> $GITHUB_ENV
+          echo "PHP_FPM_GID=$(id -g)" >> $GITHUB_ENV
+
+      - name: Checkout repository
+        uses: actions/checkout@b4ffde65f46336ab88eb53be808477a3936bae11 # v4.1.1
+        with:
+          show-progress: ${{ runner.debug == '1' && 'true' || 'false' }}
+
+      - name: Set up Node.js
+        uses: actions/setup-node@60edb5dd545a775178f52524783378180af0d1f8 # v4.0.2
+        with:
+          node-version-file: '.nvmrc'
+          cache: npm
+
+      - name: Log debug information
+        run: |
+          npm --version
+          node --version
+          curl --version
+          git --version
+          locale -a
+
+      - name: Install npm Dependencies
+        run: npm ci
+
+      - name: Install Playwright browsers
+        run: npx playwright install --with-deps
+
+      - name: Build WordPress
+        run: npm run build
+
+      - name: Start Docker environment
+        run: |
+          npm run env:start
+
+      - name: Log running Docker containers
+        run: docker ps -a
+
+      - name: Docker debug information
+        run: |
+          docker -v
+          docker compose run --rm mysql mysql --version
+          docker compose run --rm php php --version
+          docker compose run --rm php php -m
+          docker compose run --rm php php -i
+          docker compose run --rm php locale -a
+
+      - name: Install WordPress
+        env:
+          LOCAL_SCRIPT_DEBUG: ${{ inputs.LOCAL_SCRIPT_DEBUG }}
+        run: npm run env:install
+
+      - name: Install Gutenberg
+        if: ${{ inputs.install-gutenberg }}
+        run: npm run env:cli -- plugin install gutenberg --path=/var/www/${{ env.LOCAL_DIR }}
+
+      - name: Run E2E tests
+        run: npm run test:e2e
+
+      - name: Archive debug artifacts (screenshots, HTML snapshots)
+        uses: actions/upload-artifact@5d5d22a31266ced268874388b861e4b58bb5c2f3 # v4.3.1
+        if: always()
+        with:
+          name: failures-artifacts${{ inputs.LOCAL_SCRIPT_DEBUG && '-SCRIPT_DEBUG' || '' }}-${{ github.run_id }}
+          path: artifacts
+          if-no-files-found: ignore
+
+      - name: Ensure version-controlled files are not modified or deleted
+        run: git diff --exit-code
diff --git a/.github/workflows/reusable-javascript-tests.yml b/.github/workflows/reusable-javascript-tests.yml
new file mode 100644
index 0000000000000..0d7b674fb932a
--- /dev/null
+++ b/.github/workflows/reusable-javascript-tests.yml
@@ -0,0 +1,51 @@
+##
+# A reusable workflow that runs JavaScript tests.
+##
+name: JavaScript tests
+
+on:
+  workflow_call:
+
+jobs:
+  # Runs the QUnit test suite.
+  #
+  # Performs the following steps:
+  # - Checks out the repository.
+  # - Sets up Node.js.
+  # - Logs debug information about the GitHub Action runner.
+  # - Installs npm dependencies.
+  # - Run the WordPress QUnit tests.
+  # - Ensures version-controlled files are not modified or deleted.
+  test-js:
+    name: Run QUnit tests
+    runs-on: ubuntu-latest
+    permissions:
+      contents: read
+    timeout-minutes: 20
+
+    steps:
+      - name: Checkout repository
+        uses: actions/checkout@b4ffde65f46336ab88eb53be808477a3936bae11 # v4.1.1
+        with:
+          show-progress: ${{ runner.debug == '1' && 'true' || 'false' }}
+
+      - name: Set up Node.js
+        uses: actions/setup-node@60edb5dd545a775178f52524783378180af0d1f8 # v4.0.2
+        with:
+          node-version-file: '.nvmrc'
+          cache: npm
+
+      - name: Log debug information
+        run: |
+          npm --version
+          node --version
+          git --version
+
+      - name: Install npm Dependencies
+        run: npm ci
+
+      - name: Run QUnit tests
+        run: npm run grunt qunit:compiled
+
+      - name: Ensure version-controlled files are not modified or deleted
+        run: git diff --exit-code
diff --git a/.github/workflows/reusable-performance.yml b/.github/workflows/reusable-performance.yml
new file mode 100644
index 0000000000000..0eb3f30543eb3
--- /dev/null
+++ b/.github/workflows/reusable-performance.yml
@@ -0,0 +1,317 @@
+##
+# A reusable workflow that runs the performance test suite.
+##
+name: Performance Tests
+
+on:
+  workflow_call:
+    inputs:
+      LOCAL_DIR:
+        description: 'Where to run WordPress from.'
+        required: false
+        type: 'string'
+        default: 'build'
+      BASE_TAG:
+        description: 'The version being used for baseline measurements.'
+        required: false
+        type: 'string'
+        default: '6.1.1'
+      memcached:
+        description: 'Whether to enable memcached.'
+        required: false
+        type: 'boolean'
+        default: false
+
+env:
+  PUPPETEER_SKIP_DOWNLOAD: ${{ true }}
+
+  # Performance testing should be performed in an environment reflecting a standard production environment.
+  LOCAL_WP_DEBUG: false
+  LOCAL_SCRIPT_DEBUG: false
+  LOCAL_SAVEQUERIES: false
+  LOCAL_WP_DEVELOPMENT_MODE: "''"
+
+  # This workflow takes two sets of measurements — one for the current commit,
+  # and another against a consistent version that is used as a baseline measurement.
+  # This is done to isolate variance in measurements caused by the GitHub runners
+  # from differences caused by code changes between commits. The BASE_TAG value here
+  # represents the version being used for baseline measurements. It should only be
+  # changed if we want to normalize results against a different baseline.
+  BASE_TAG: ${{ inputs.BASE_TAG }}
+  LOCAL_DIR: ${{ inputs.LOCAL_DIR }}
+  TARGET_REF: ${{ github.event_name == 'pull_request' && github.event.pull_request.base.ref || '' }}
+  TARGET_SHA: ${{ github.event_name == 'pull_request' && github.event.pull_request.base.sha || github.event.before }}
+
+  LOCAL_PHP_MEMCACHED: ${{ inputs.memcached }}
+
+jobs:
+  # Performs the following steps:
+  # - Configure environment variables.
+  # - Checkout repository.
+  # - Set up Node.js.
+  # - Log debug information.
+  # - Install npm dependencies.
+  # - Install Playwright browsers.
+  # - Build WordPress.
+  # - Start Docker environment.
+  # - Log running Docker containers.
+  # - Docker debug information.
+  # - Install WordPress.
+  # - Install WordPress Importer plugin.
+  # - Import mock data.
+  # - Deactivate WordPress Importer plugin.
+  # - Update permalink structure.
+  # - Install additional languages.
+  # - Disable external HTTP requests.
+  # - Disable cron.
+  # - List defined constants.
+  # - Install MU plugin.
+  # - Run performance tests (current commit).
+  # - Download previous build artifact (target branch or previous commit).
+  # - Download artifact.
+  # - Unzip the build.
+  # - Run any database upgrades.
+  # - Flush cache.
+  # - Delete expired transients.
+  # - Run performance tests (previous/target commit).
+  # - Set the environment to the baseline version.
+  # - Run any database upgrades.
+  # - Flush cache.
+  # - Delete expired transients.
+  # - Run baseline performance tests.
+  # - Archive artifacts.
+  # - Compare results.
+  # - Add workflow summary.
+  # - Set the base sha.
+  # - Set commit details.
+  # - Publish performance results.
+  # - Ensure version-controlled files are not modified or deleted.
+  performance:
+    name: Run tests
+    runs-on: ubuntu-latest
+    permissions:
+      contents: read
+    if: ${{ ( github.repository == 'WordPress/wordpress-develop' || github.event_name == 'pull_request' ) && ! contains( github.event.before, '00000000' ) }}
+
+    steps:
+      - name: Configure environment variables
+        run: |
+          echo "PHP_FPM_UID=$(id -u)" >> $GITHUB_ENV
+          echo "PHP_FPM_GID=$(id -g)" >> $GITHUB_ENV
+
+      - name: Checkout repository
+        uses: actions/checkout@b4ffde65f46336ab88eb53be808477a3936bae11 # v4.1.1
+        with:
+          show-progress: ${{ runner.debug == '1' && 'true' || 'false' }}
+
+      - name: Set up Node.js
+        uses: actions/setup-node@60edb5dd545a775178f52524783378180af0d1f8 # v4.0.2
+        with:
+          node-version-file: '.nvmrc'
+          cache: npm
+
+      - name: Log debug information
+        run: |
+          npm --version
+          node --version
+          curl --version
+          git --version
+          locale -a
+
+      - name: Install npm dependencies
+        run: npm ci
+
+      - name: Install Playwright browsers
+        run: npx playwright install --with-deps chromium
+
+      - name: Build WordPress
+        run: npm run build
+
+      - name: Start Docker environment
+        run: npm run env:start
+
+      - name: Install object cache drop-in
+        if: ${{ inputs.memcached }}
+        run: cp src/wp-content/object-cache.php build/wp-content/object-cache.php
+
+      - name: Log running Docker containers
+        run: docker ps -a
+
+      - name: Docker debug information
+        run: |
+          docker -v
+          docker compose run --rm mysql mysql --version
+          docker compose run --rm php php --version
+          docker compose run --rm php php -m
+          docker compose run --rm php php -i
+          docker compose run --rm php locale -a
+
+      - name: Install WordPress
+        run: npm run env:install
+
+      - name: Install WordPress Importer plugin
+        run: npm run env:cli -- plugin install wordpress-importer --activate --path=/var/www/${{ env.LOCAL_DIR }}
+
+      - name: Import mock data
+        run: |
+          curl -O https://raw.githubusercontent.com/WordPress/theme-test-data/b9752e0533a5acbb876951a8cbb5bcc69a56474c/themeunittestdata.wordpress.xml
+          npm run env:cli -- import themeunittestdata.wordpress.xml --authors=create --path=/var/www/${{ env.LOCAL_DIR }}
+          rm themeunittestdata.wordpress.xml
+
+      - name: Deactivate WordPress Importer plugin
+        run: npm run env:cli -- plugin deactivate wordpress-importer --path=/var/www/${{ env.LOCAL_DIR }}
+
+      - name: Update permalink structure
+        run: npm run env:cli -- rewrite structure '/%year%/%monthnum%/%postname%/' --path=/var/www/${{ env.LOCAL_DIR }}
+
+      - name: Install additional languages
+        run: |
+          npm run env:cli -- language core install de_DE --path=/var/www/${{ env.LOCAL_DIR }}
+          npm run env:cli -- language plugin install de_DE --all --path=/var/www/${{ env.LOCAL_DIR }}
+          npm run env:cli -- language theme install de_DE --all --path=/var/www/${{ env.LOCAL_DIR }}
+
+      # Prevent background update checks from impacting test stability.
+      - name: Disable external HTTP requests
+        run: npm run env:cli -- config set WP_HTTP_BLOCK_EXTERNAL true --raw --type=constant --path=/var/www/${{ env.LOCAL_DIR }}
+
+      # Prevent background tasks from impacting test stability.
+      - name: Disable cron
+        run: npm run env:cli -- config set DISABLE_WP_CRON true --raw --type=constant --path=/var/www/${{ env.LOCAL_DIR }}
+
+      - name: List defined constants
+        run: npm run env:cli -- config list --path=/var/www/${{ env.LOCAL_DIR }}
+
+      - name: Install MU plugin
+        run: |
+          mkdir ./${{ env.LOCAL_DIR }}/wp-content/mu-plugins
+          cp ./tests/performance/wp-content/mu-plugins/server-timing.php ./${{ env.LOCAL_DIR }}/wp-content/mu-plugins/server-timing.php
+
+      - name: Run performance tests (current commit)
+        run: npm run test:performance
+
+      - name: Download previous build artifact (target branch or previous commit)
+        uses: actions/github-script@60a0d83039c74a4aee543508d2ffcb1c3799cdea # v7.0.1
+        id: get-previous-build
+        with:
+          script: |
+            const artifacts = await github.rest.actions.listArtifactsForRepo({
+              owner: context.repo.owner,
+              repo: context.repo.repo,
+              name: 'wordpress-build-' + process.env.TARGET_SHA,
+            });
+
+            const matchArtifact = artifacts.data.artifacts[0];
+
+            if ( ! matchArtifact ) {
+              core.setFailed( 'No artifact found!' );
+              return false;
+            }
+
+            const download = await github.rest.actions.downloadArtifact( {
+              owner: context.repo.owner,
+              repo: context.repo.repo,
+              artifact_id: matchArtifact.id,
+              archive_format: 'zip',
+            } );
+
+            const fs = require( 'fs' );
+            fs.writeFileSync( '${{ github.workspace }}/before.zip', Buffer.from( download.data ) )
+
+            return true;
+
+      - name: Unzip the build
+        if: ${{ steps.get-previous-build.outputs.result }}
+        run: |
+          unzip ${{ github.workspace }}/before.zip
+          unzip -o ${{ github.workspace }}/wordpress.zip
+
+      - name: Run any database upgrades
+        if: ${{ steps.get-previous-build.outputs.result }}
+        run: npm run env:cli -- core update-db --path=/var/www/${{ env.LOCAL_DIR }}
+
+      - name: Flush cache
+        if: ${{ steps.get-previous-build.outputs.result }}
+        run: npm run env:cli -- cache flush --path=/var/www/${{ env.LOCAL_DIR }}
+
+      - name: Delete expired transients
+        if: ${{ steps.get-previous-build.outputs.result }}
+        run: npm run env:cli -- transient delete --expired --path=/var/www/${{ env.LOCAL_DIR }}
+
+      - name: Run target performance tests (previous/target commit)
+        if: ${{ steps.get-previous-build.outputs.result }}
+        env:
+          TEST_RESULTS_PREFIX: before
+        run: npm run test:performance
+
+      - name: Set the environment to the baseline version
+        if: ${{ github.event_name == 'push' && github.ref == 'refs/heads/trunk' }}
+        run: |
+          npm run env:cli -- core update --version=${{ env.BASE_TAG }} --force --path=/var/www/${{ env.LOCAL_DIR }}
+          npm run env:cli -- core version --path=/var/www/${{ env.LOCAL_DIR }}
+
+      - name: Run any database upgrades
+        if: ${{ github.event_name == 'push' && github.ref == 'refs/heads/trunk' }}
+        run: npm run env:cli -- core update-db --path=/var/www/${{ env.LOCAL_DIR }}
+
+      - name: Flush cache
+        if: ${{ github.event_name == 'push' && github.ref == 'refs/heads/trunk' }}
+        run: npm run env:cli -- cache flush --path=/var/www/${{ env.LOCAL_DIR }}
+
+      - name: Delete expired transients
+        if: ${{ github.event_name == 'push' && github.ref == 'refs/heads/trunk' }}
+        run: npm run env:cli -- transient delete --expired --path=/var/www/${{ env.LOCAL_DIR }}
+
+      - name: Run baseline performance tests
+        if: ${{ github.event_name == 'push' && github.ref == 'refs/heads/trunk' }}
+        env:
+          TEST_RESULTS_PREFIX: base
+        run: npm run test:performance
+
+      - name: Archive artifacts
+        uses: actions/upload-artifact@5d5d22a31266ced268874388b861e4b58bb5c2f3 # v4.3.1
+        if: always()
+        with:
+          name: performance-artifacts${{ inputs.memcached && '-memcached' || '' }}-${{ github.run_id }}
+          path: artifacts
+          if-no-files-found: ignore
+
+      - name: Compare results
+        run: node ./tests/performance/compare-results.js ${{ runner.temp }}/summary.md
+
+      - name: Add workflow summary
+        run: cat ${{ runner.temp }}/summary.md >> $GITHUB_STEP_SUMMARY
+
+      - name: Set the base sha
+        # Only needed when publishing results.
+        if: ${{ github.event_name == 'push' && github.ref == 'refs/heads/trunk' && ! inputs.memcached }}
+        uses: actions/github-script@60a0d83039c74a4aee543508d2ffcb1c3799cdea # v7.0.1
+        id: base-sha
+        with:
+          github-token: ${{ secrets.GITHUB_TOKEN }}
+          script: |
+            const baseRef = await github.rest.git.getRef({ owner: context.repo.owner, repo: context.repo.repo, ref: 'tags/${{ env.BASE_TAG }}' });
+            return baseRef.data.object.sha;
+
+      - name: Set commit details
+        # Only needed when publishing results.
+        if: ${{ github.event_name == 'push' && github.ref == 'refs/heads/trunk' && ! inputs.memcached }}
+        uses: actions/github-script@60a0d83039c74a4aee543508d2ffcb1c3799cdea # v7.0.1
+        id: commit-timestamp
+        with:
+          github-token: ${{ secrets.GITHUB_TOKEN }}
+          script: |
+            const commit_details = await github.rest.git.getCommit({ owner: context.repo.owner, repo: context.repo.repo, commit_sha: context.sha });
+            return parseInt((new Date( commit_details.data.author.date ).getTime() / 1000).toFixed(0))
+
+      - name: Publish performance results
+        # Only publish results on pushes to trunk.
+        if: ${{ github.event_name == 'push' && github.ref == 'refs/heads/trunk' && ! inputs.memcached }}
+        env:
+          BASE_SHA: ${{ steps.base-sha.outputs.result }}
+          COMMITTED_AT: ${{ steps.commit-timestamp.outputs.result }}
+          CODEVITALS_PROJECT_TOKEN: ${{ secrets.CODEVITALS_PROJECT_TOKEN }}
+          HOST_NAME: "www.codevitals.run"
+        run: node ./tests/performance/log-results.js $CODEVITALS_PROJECT_TOKEN trunk $GITHUB_SHA $BASE_SHA $COMMITTED_AT $HOST_NAME
+
+      - name: Ensure version-controlled files are not modified or deleted
+        run: git diff --exit-code
diff --git a/.github/workflows/reusable-php-compatibility.yml b/.github/workflows/reusable-php-compatibility.yml
new file mode 100644
index 0000000000000..1a6a6b128747b
--- /dev/null
+++ b/.github/workflows/reusable-php-compatibility.yml
@@ -0,0 +1,85 @@
+##
+# A reusable workflow that runs PHP compatibility tests.
+##
+name: PHP Compatibility
+
+on:
+  workflow_call:
+    inputs:
+      php-version:
+        description: 'The PHP version to use.'
+        required: false
+        type: 'string'
+        default: 'latest'
+
+jobs:
+  # Runs PHP compatibility tests.
+  #
+  # Violations are reported inline with annotations.
+  #
+  # Performs the following steps:
+  # - Checks out the repository.
+  # - Sets up PHP.
+  # - Logs debug information.
+  # - Configures caching for PHP compatibility scans.
+  # - Installs Composer dependencies.
+  # - Make Composer packages available globally.
+  # - Runs the PHP compatibility tests.
+  # - Generate a report for displaying issues as pull request annotations.
+  # - Ensures version-controlled files are not modified or deleted.
+  php-compatibility:
+    name: Run compatibility checks
+    runs-on: ubuntu-latest
+    permissions:
+      contents: read
+    timeout-minutes: 20
+
+    steps:
+      - name: Checkout repository
+        uses: actions/checkout@b4ffde65f46336ab88eb53be808477a3936bae11 # v4.1.1
+        with:
+          show-progress: ${{ runner.debug == '1' && 'true' || 'false' }}
+
+      - name: Set up PHP
+        uses: shivammathur/setup-php@a4e22b60bbb9c1021113f2860347b0759f66fe5d # v2.30.0
+        with:
+          php-version: ${{ inputs.php-version }}
+          coverage: none
+          tools: cs2pr
+
+      - name: Log debug information
+        run: |
+          composer --version
+
+      # This date is used to ensure that the PHP compatibility cache is cleared at least once every week.
+      # http://man7.org/linux/man-pages/man1/date.1.html
+      - name: "Get last Monday's date"
+        id: get-date
+        run: echo "date=$(/bin/date -u --date='last Mon' "+%F")" >> $GITHUB_OUTPUT
+
+      - name: Cache PHP compatibility scan cache
+        uses: actions/cache@ab5e6d0c87105b4c9c2047343972218f562e4319 # v4.0.1
+        with:
+          path: .cache/phpcompat.json
+          key: ${{ runner.os }}-date-${{ steps.get-date.outputs.date }}-php-${{ inputs.php-version }}-phpcompat-cache-${{ hashFiles('**/composer.json', 'phpcompat.xml.dist') }}
+
+      # Since Composer dependencies are installed using `composer update` and no lock file is in version control,
+      # passing a custom cache suffix ensures that the cache is flushed at least once per week.
+      - name: Install Composer dependencies
+        uses: ramsey/composer-install@57532f8be5bda426838819c5ee9afb8af389d51a # v3.0.0
+        with:
+          custom-cache-suffix: ${{ steps.get-date.outputs.date }}
+
+      - name: Make Composer packages available globally
+        run: echo "${PWD}/vendor/bin" >> $GITHUB_PATH
+
+      - name: Run PHP compatibility tests
+        id: phpcs
+        run: phpcs --standard=phpcompat.xml.dist --report-full --report-checkstyle=./.cache/phpcs-compat-report.xml
+
+      - name: Show PHPCompatibility results in PR
+        if: ${{ always() && steps.phpcs.outcome == 'failure' }}
+        run: cs2pr ./.cache/phpcs-compat-report.xml
+
+      - name: Ensure version-controlled files are not modified or deleted
+        run: git diff --exit-code
diff --git a/.github/workflows/phpunit-tests-run.yml b/.github/workflows/reusable-phpunit-tests.yml
similarity index 99%
rename from .github/workflows/phpunit-tests-run.yml
rename to .github/workflows/reusable-phpunit-tests.yml
index 9978fd9bf70fb..60949915e4d1c 100644
--- a/.github/workflows/phpunit-tests-run.yml
+++ b/.github/workflows/reusable-phpunit-tests.yml
@@ -1,5 +1,5 @@
 ##
-# A callable workflow that runs the PHPUnit test suite with the specified configuration.
+# A reusable workflow that runs the PHPUnit test suite with the specified configuration.
 ##
 name: Run PHPUnit tests
 
diff --git a/.github/workflows/callable-test-core-build-process.yml b/.github/workflows/reusable-test-core-build-process.yml
similarity index 92%
rename from .github/workflows/callable-test-core-build-process.yml
rename to .github/workflows/reusable-test-core-build-process.yml
index 7c2bd9c80c75f..caeb7afab7555 100644
--- a/.github/workflows/callable-test-core-build-process.yml
+++ b/.github/workflows/reusable-test-core-build-process.yml
@@ -1,5 +1,5 @@
 ##
-# A callable workflow that tests the WordPress Core build process.
+# A reusable workflow that tests the WordPress Core build process.
 ##
 name: Test the WordPress Build Process
 
@@ -16,6 +16,11 @@ on:
         required: false
         type: 'string'
         default: 'src'
+      test-emoji:
+        description: 'Whether to run the grunt precommit:emoji script.'
+        required: false
+        type: 'boolean'
+        default: true
 
 env:
   PUPPETEER_SKIP_DOWNLOAD: ${{ true }}
@@ -62,6 +67,7 @@ jobs:
         run: npm ci
 
       - name: Run Emoji precommit task
+        if: ${{ inputs.test-emoji }}
         run: npm run grunt precommit:emoji
         env:
           GH_TOKEN: ${{ secrets.GITHUB_TOKEN }}
diff --git a/.github/workflows/callable-test-gutenberg-build-process.yml b/.github/workflows/reusable-test-gutenberg-build-process.yml
similarity index 98%
rename from .github/workflows/callable-test-gutenberg-build-process.yml
rename to .github/workflows/reusable-test-gutenberg-build-process.yml
index 755b169caee92..150e40d109119 100644
--- a/.github/workflows/callable-test-gutenberg-build-process.yml
+++ b/.github/workflows/reusable-test-gutenberg-build-process.yml
@@ -1,5 +1,5 @@
 ##
-# A callable workflow that tests the Gutenberg plugin build process when run within a wordpress-develop checkout.
+# A reusable workflow that tests the Gutenberg plugin build process when run within a wordpress-develop checkout.
 ##
 name: Test the Gutenberg plugin Build Process
 
diff --git a/.github/workflows/upgrade-testing-run.yml b/.github/workflows/reusable-upgrade-testing.yml
similarity index 98%
rename from .github/workflows/upgrade-testing-run.yml
rename to .github/workflows/reusable-upgrade-testing.yml
index 0235d38f95b76..8e467c20ccbc9 100644
--- a/.github/workflows/upgrade-testing-run.yml
+++ b/.github/workflows/reusable-upgrade-testing.yml
@@ -1,4 +1,4 @@
-# A callable workflow that runs WordPress upgrade testing under the conditions provided.
+# A reusable workflow that runs WordPress upgrade testing under the conditions provided.
 name: Upgrade Tests
 
 on:
diff --git a/.github/workflows/test-build-processes.yml b/.github/workflows/test-build-processes.yml
index e768c01a0b3e0..6e8ee69ec6770 100644
--- a/.github/workflows/test-build-processes.yml
+++ b/.github/workflows/test-build-processes.yml
@@ -31,7 +31,7 @@ jobs:
   # Tests the WordPress Core build process on multiple operating systems.
   test-core-build-process:
     name: Core running from ${{ matrix.directory }}
-    uses: WordPress/wordpress-develop/.github/workflows/callable-test-core-build-process.yml@trunk
+    uses: WordPress/wordpress-develop/.github/workflows/reusable-test-core-build-process.yml@trunk
     permissions:
       contents: read
     if: ${{ github.repository == 'WordPress/wordpress-develop' || github.event_name == 'pull_request' }}
@@ -54,7 +54,7 @@ jobs:
   # See https://docs.github.com/en/actions/learn-github-actions/contexts#context-availability.
   test-core-build-process-macos:
     name: Core running from ${{ matrix.directory }}
-    uses: WordPress/wordpress-develop/.github/workflows/callable-test-core-build-process.yml@trunk
+    uses: WordPress/wordpress-develop/.github/workflows/reusable-test-core-build-process.yml@trunk
     permissions:
       contents: read
     if: ${{ github.repository == 'WordPress/wordpress-develop' }}
@@ -70,7 +70,7 @@ jobs:
   # Tests the Gutenberg plugin build process on multiple operating systems when run within a wordpress-develop checkout.
   test-gutenberg-build-process:
     name: Gutenberg running from ${{ matrix.directory }}
-    uses: WordPress/wordpress-develop/.github/workflows/callable-test-gutenberg-build-process.yml@trunk
+    uses: WordPress/wordpress-develop/.github/workflows/reusable-test-gutenberg-build-process.yml@trunk
     permissions:
       contents: read
     if: ${{ github.repository == 'WordPress/wordpress-develop' || github.event_name == 'pull_request' }}
@@ -93,7 +93,7 @@ jobs:
   # See https://docs.github.com/en/actions/learn-github-actions/contexts#context-availability.
   test-gutenberg-build-process-macos:
     name: Gutenberg running from ${{ matrix.directory }}
-    uses: WordPress/wordpress-develop/.github/workflows/callable-test-gutenberg-build-process.yml@trunk
+    uses: WordPress/wordpress-develop/.github/workflows/reusable-test-gutenberg-build-process.yml@trunk
     permissions:
       contents: read
     if: ${{ github.repository == 'WordPress/wordpress-develop' }}
diff --git a/.github/workflows/upgrade-testing.yml b/.github/workflows/upgrade-testing.yml
index fe2d4dc24fae5..1ffe4bfc585ac 100644
--- a/.github/workflows/upgrade-testing.yml
+++ b/.github/workflows/upgrade-testing.yml
@@ -35,7 +35,7 @@ jobs:
   # Spawns upgrade testing from WordPress 6.x versions with MySQL.
   upgrade-tests-wp-6x-mysql:
     name: ${{ matrix.wp }} to ${{ inputs.new-version && inputs.new-version || 'latest' }}
-    uses: WordPress/wordpress-develop/.github/workflows/upgrade-testing-run.yml@trunk
+    uses: WordPress/wordpress-develop/.github/workflows/reusable-upgrade-testing.yml@trunk
     if: ${{ github.repository == 'WordPress/wordpress-develop' || github.event_name == 'pull_request' }}
     permissions:
       contents: read
@@ -60,7 +60,7 @@ jobs:
   # Spawns upgrade testing from WordPress 5.x versions on PHP 7.x with MySQL.
   upgrade-tests-wp-5x-php-7x-mysql:
     name: ${{ matrix.wp }} to ${{ inputs.new-version && inputs.new-version || 'latest' }}
-    uses: WordPress/wordpress-develop/.github/workflows/upgrade-testing-run.yml@trunk
+    uses: WordPress/wordpress-develop/.github/workflows/reusable-upgrade-testing.yml@trunk
     if: ${{ github.repository == 'WordPress/wordpress-develop' || github.event_name == 'pull_request' }}
     strategy:
       fail-fast: false
@@ -87,7 +87,7 @@ jobs:
   # - array/string offset with curly braces.
   upgrade-tests-wp-5x-php-8x-mysql:
     name: ${{ matrix.wp }} to ${{ inputs.new-version && inputs.new-version || 'latest' }}
-    uses: WordPress/wordpress-develop/.github/workflows/upgrade-testing-run.yml@trunk
+    uses: WordPress/wordpress-develop/.github/workflows/reusable-upgrade-testing.yml@trunk
     if: ${{ github.repository == 'WordPress/wordpress-develop' || github.event_name == 'pull_request' }}
     strategy:
       fail-fast: false
@@ -110,7 +110,7 @@ jobs:
   # Spawns upgrade testing from WordPress 4.x versions on PHP 7.x with MySQL.
   upgrade-tests-wp-4x-php-7x-mysql:
     name: ${{ matrix.wp }} to ${{ inputs.new-version && inputs.new-version || 'latest' }}
-    uses: WordPress/wordpress-develop/.github/workflows/upgrade-testing-run.yml@trunk
+    uses: WordPress/wordpress-develop/.github/workflows/reusable-upgrade-testing.yml@trunk
     if: ${{ github.repository == 'WordPress/wordpress-develop' || github.event_name == 'pull_request' }}
     strategy:
       fail-fast: false
@@ -137,7 +137,7 @@ jobs:
   # - array/string offset with curly braces.
   upgrade-tests-wp-4x-php-8x-mysql:
     name: ${{ matrix.wp }} to ${{ inputs.new-version && inputs.new-version || 'latest' }}
-    uses: WordPress/wordpress-develop/.github/workflows/upgrade-testing-run.yml@trunk
+    uses: WordPress/wordpress-develop/.github/workflows/reusable-upgrade-testing.yml@trunk
     if: ${{ github.repository == 'WordPress/wordpress-develop' || github.event_name == 'pull_request' }}
     strategy:
       fail-fast: false