diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 15bf6dfd..2becbec0 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -3,7 +3,7 @@ on: [push, pull_request]
 
 jobs:
   test:
-    runs-on: 'ubuntu-latest'
+    runs-on: ubuntu-22.04
 
     services:
       postgres:
@@ -14,14 +14,14 @@ jobs:
         ports:
           - 5432:5432
         options: --health-cmd pg_isready --health-interval 10s --health-timeout 5s --health-retries 3
+
       mariadb:
-        image: mariadb:10.6
+        image: mariadb:10
         env:
           MYSQL_USER: 'root'
           MYSQL_ALLOW_EMPTY_PASSWORD: "true"
           MYSQL_CHARACTER_SET_SERVER: "utf8mb4"
           MYSQL_COLLATION_SERVER: "utf8mb4_unicode_ci"
-
         ports:
           - 3306:3306
         options: --health-cmd="mysqladmin ping" --health-interval 10s --health-timeout 5s --health-retries 3
@@ -30,6 +30,9 @@ jobs:
       fail-fast: false
       matrix:
         include:
+          - php: '8.3'
+            moodle-branch: 'MOODLE_404_STABLE'
+            database: 'pgsql'
           - php: '8.2'
             moodle-branch: 'MOODLE_403_STABLE'
             database: 'mariadb'
@@ -45,7 +48,7 @@ jobs:
 
     steps:
       - name: Checkout
-        uses: actions/checkout@v3
+        uses: actions/checkout@v4
         with:
           path: plugin
 
@@ -60,12 +63,12 @@ jobs:
 
       - name: Deploy moodle-plugin-ci
         run: |
-          composer create-project -n --no-dev --prefer-dist moodlehq/moodle-plugin-ci ci ^3
-          # Add dirs to $PATH
+          composer create-project -n --no-dev --prefer-dist moodlehq/moodle-plugin-ci ci ^4
           echo $(cd ci/bin; pwd) >> $GITHUB_PATH
           echo $(cd ci/vendor/bin; pwd) >> $GITHUB_PATH
-          # PHPUnit depends on en_AU.UTF-8 locale
           sudo locale-gen en_AU.UTF-8
+          # Install nvm.
+          curl -o- https://raw.githubusercontent.com/nvm-sh/nvm/v0.39.7/install.sh | bash
 
       - name: Install Moodle
         # Need explicit IP to stop mysql client fail on attempt to use unix socket.