diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 50f33d43..b81774a3 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -36,14 +36,14 @@ jobs:
       matrix:
         # All the versions, OS, and dependency levels we want to support
         os: [ubuntu]         # TODO: windows, macos
-        php: [ '8.0', '8.1', '8.2', '8.3' ]
+        php: [ '8.1', '8.2', '8.3', '8.4' ]
         dependency: [ stable ]
         # Our code has paths for with- and without- XDebug, and we want to test
         # both of them.
         # @see https://xdebug.org/docs/all_settings#mode
         xdebug3-mode: ['develop,coverage', 'coverage']
         include:
-          - php: '8.0'
+          - php: '8.1'
             os: 'ubuntu'
             dependency: 'lowest'
             xdebug3-mode: 'develop,coverage'
@@ -73,8 +73,22 @@ jobs:
           key: ${{ matrix.os }}-composer-${{ hashFiles('**/composer.json') }}-${{ matrix.dependency }}-
           restore-keys: ${{ matrix.os }}-composer-${{ matrix.dependency }}-
 
-      - name: Install dependencies
+      - name: Install dependencies PHP < 8.4
+        if: matrix.php != '8.4'
         run: composer update --prefer-${{ matrix.dependency }} --prefer-dist --no-interaction
 
-      - name: Execute tests
+      - name: Execute tests PHP < 8.4
+        if: matrix.php != '8.4'
         run: composer test
+
+      # This is a temporary workaround until vimeo/psalm is updated to support PHP 8.4.
+      # See https://github.com/vimeo/psalm/issues/11107
+      - name: Install dependencies PHP 8.4
+        if: matrix.php == '8.4'
+        run: composer update --prefer-${{ matrix.dependency }} --prefer-dist --no-interaction --ignore-platform-reqs
+
+      - name: Execute tests PHP 8.4
+        if: matrix.php == '8.4'
+        run: |
+          ./vendor/bin/phpcs --standard=PSR2 ./src ./tests
+          ./vendor/bin/phpunit --coverage-clover build/logs/clover.xml