diff --git a/.github/actions/parse-version/script.php b/.github/actions/parse-version/script.php
index e4875104..a4c0d5fd 100644
--- a/.github/actions/parse-version/script.php
+++ b/.github/actions/parse-version/script.php
@@ -105,6 +105,59 @@ function container_image_name($moodle_branch, $php) {
     return "ghcr.io/catalyst/$repo:latest";
 }
 
+/**
+ * Resolve a MOODLE_XXX_STABLE branch to a Moodle minor (10 digit) version.
+ *
+ * @param string $moodleBranch
+ * @param array $updates
+ * @return string
+ */
+function moodle_minor_version($moodleBranch, array $updates): string {
+    if (!preg_match('/^MOODLE_(\d+)_STABLE$/', $moodleBranch, $matches)) {
+        return '';
+    }
+
+    $series = $matches[1];
+    $major = substr($series, 0, 1);
+    // Cast via int to strip leading zeros, then back to string for consistent branch key comparisons.
+    // This normalizes values used in the Moodle updates API map keys.
+    // Example: MOODLE_401_STABLE => 4.1, MOODLE_3011_STABLE => 3.11.
+    $minor = (string)((int)substr($series, 1));
+
+    $branch = $major . '.' . $minor;
+    foreach ($updates as $update) {
+        if (($update['branch'] ?? '') === $branch) {
+            return (string)($update['version'] ?? '');
+        }
+    }
+
+    return '';
+}
+
+/**
+ * Build a deterministic pgseed image reference for a matrix entry.
+ *
+ * @param array $entry
+ * @return string
+ */
+function pgseed_image_name(array $entry): string {
+    if (($entry['database'] ?? '') !== 'pgsql') {
+        return '';
+    }
+
+    $minor = $entry['moodle-minor'] ?? '';
+    $pgsql = $entry['pgsql-ver'] ?? '';
+    $php = $entry['php'] ?? '';
+    $branch = $entry['moodle-branch'] ?? '';
+    if ($minor === '' || $pgsql === '' || $php === '' || $branch === '') {
+        return '';
+    }
+
+    $branchSlug = str_replace('_', '-', strtolower($branch));
+    $tag = "{$branchSlug}-php{$php}-pg{$pgsql}-m{$minor}";
+    return "ghcr.io/catalyst/catalyst-moodle-workflows-pgseed:{$tag}";
+}
+
 $preparedMatrix = array_filter($matrix['include'], function($entry) use($plugin, $updates, $matrix) {
 
     if (!isset($entry)) {
@@ -205,9 +258,11 @@ function container_image_name($moodle_branch, $php) {
 
 
 // Add container image name and short branch name to each entry
-$finalMatrix = array_map(function($entry) {
+$finalMatrix = array_map(function($entry) use ($updates) {
     $entry['container'] = container_image_name($entry['moodle-branch'], $entry['php']);
     $entry['moodle-branch-short'] = preg_replace('/MOODLE_(.*)_STABLE/', '$1', $entry['moodle-branch']);
+    $entry['moodle-minor'] = moodle_minor_version($entry['moodle-branch'], $updates);
+    $entry['pgseed-image'] = pgseed_image_name($entry);
     return $entry;
 }, array_values($preparedMatrix));
 
diff --git a/.github/plugin/setup/action.yml b/.github/plugin/setup/action.yml
index 7195b2b6..6772cc84 100644
--- a/.github/plugin/setup/action.yml
+++ b/.github/plugin/setup/action.yml
@@ -107,6 +107,36 @@ runs:
         ((test -f plugin/patch/${{ inputs.moodle_branch }}.diff && cd $GITHUB_WORKSPACE/moodletemp && git am --whitespace=nowarn < ../plugin/patch/${{ inputs.moodle_branch }}.diff) || echo No patch found;)
       shell: bash
 
+    - name: Apply MDL-88495 phpunit snapshot patch
+      if: ${{ always() }}
+      run: |
+        set -euo pipefail
+        cd "$GITHUB_WORKSPACE/moodletemp"
+        if grep -q -- "--upgrade" public/admin/tool/phpunit/cli/util.php; then
+          echo "MDL-88495 patch already present in this Moodle checkout."
+          exit 0
+        fi
+        # Temporary upstream patch for MDL-88495 phpunit snapshot/restore/upgrade support.
+        patch_url="https://github.com/moodle/moodle/commit/e812521f260b571f05ced5efd3bb443a455bbf78.patch"
+        patch_file="/tmp/mdl88495-phpunitci.patch"
+        # SHA256 for commit patch e812521f260b571f05ced5efd3bb443a455bbf78.
+        expected_sha256="4aee5364e688fb22170bc902887c623439f00cf45baad54e8dedfd6e66594290"
+        curl -fsSL "$patch_url" -o "$patch_file"
+        actual_sha256="$(sha256sum "$patch_file" | awk '{print $1}')"
+        if [ "$actual_sha256" != "$expected_sha256" ]; then
+          echo "Patch checksum mismatch for MDL-88495 patch."
+          echo "Expected: $expected_sha256"
+          echo "Actual:   $actual_sha256"
+          exit 1
+        fi
+        if ! git am --3way --whitespace=nowarn /tmp/mdl88495-phpunitci.patch; then
+          git am --abort || true
+          echo "MDL-88495 patch did not apply cleanly on ${MOODLE_BRANCH}; continuing without patch (PHPUnit snapshot/restore features unavailable)."
+        fi
+      shell: bash
+      env:
+        MOODLE_BRANCH: ${{ inputs.moodle_branch }}
+
     - name: Install Moodle and Plugin
       if: ${{ inputs.database != '' }}
       # Install moodle, but use our temporary directory to include any potential core patches that have been applied.
@@ -123,4 +153,4 @@ runs:
       shell: bash
       env:
         DB: ${{ inputs.database }}
-        MOODLE_BRANCH: ${{ inputs.moodle_branch }}
\ No newline at end of file
+        MOODLE_BRANCH: ${{ inputs.moodle_branch }}
diff --git a/.github/workflows/build-pgseed.yml b/.github/workflows/build-pgseed.yml
new file mode 100644
index 00000000..ddd3cad3
--- /dev/null
+++ b/.github/workflows/build-pgseed.yml
@@ -0,0 +1,147 @@
+name: Build pgseed images
+
+on:
+  workflow_dispatch:
+  schedule:
+    # Runs weekly (every Monday at 06:15 UTC) to refresh tags when Moodle minor versions roll forward.
+    - cron: '15 6 * * 1'
+  push:
+    branches:
+      - main
+    paths:
+      - '.github/actions/matrix/matrix_includes.yml'
+      - 'docker/pgseed/**'
+      - '.github/workflows/build-pgseed.yml'
+
+permissions:
+  contents: read
+
+jobs:
+  build-matrix:
+    runs-on: ubuntu-latest
+    outputs:
+      matrix: ${{ steps.set-matrix.outputs.matrix }}
+    steps:
+      - name: Checkout repository
+        uses: actions/checkout@v4
+
+      - name: Set up Python
+        uses: actions/setup-python@v5
+        with:
+          python-version: '3.x'
+
+      - name: Install PyYAML
+        run: pip install pyyaml
+
+      - name: Build pgseed matrix
+        id: set-matrix
+        run: |
+          import json
+          import os
+          import sys
+          import urllib.request
+          import yaml
+
+          with open('.github/actions/matrix/matrix_includes.yml', encoding='utf-8') as f:
+              data = yaml.safe_load(f)
+
+          MOODLE_UPDATES_QUERY_BRANCH = '3.8'
+          # branch=3.8 is accepted by this endpoint and still returns the full core updates list.
+          # version=0.0 requests the full available set rather than filtering to a real installed version.
+          updates_url = f'https://download.moodle.org/api/1.3/updates.php?format=json&version=0.0&branch={MOODLE_UPDATES_QUERY_BRANCH}'
+          try:
+              with urllib.request.urlopen(updates_url, timeout=30) as response:
+                  updates_data = json.loads(response.read().decode('utf-8'))
+          except Exception as exc:
+              print(f'Failed to fetch Moodle updates from {updates_url}: {exc}', file=sys.stderr)
+              print('Please retry the workflow or run it manually once the API is reachable.', file=sys.stderr)
+              raise
+
+          branch_to_minor = {
+              row['branch']: str(row['version'])
+              for row in updates_data.get('updates', {}).get('core', [])
+              if isinstance(row, dict) and row.get('branch') and row.get('version')
+          }
+
+          def to_minor_branch(moodle_branch):
+              if not moodle_branch.startswith('MOODLE_') or not moodle_branch.endswith('_STABLE'):
+                  return ''
+              digits = moodle_branch[len('MOODLE_'):-len('_STABLE')]
+              if not digits.isdigit() or len(digits) < 2:
+                  return ''
+              major = digits[0]
+              minor = digits[1:].lstrip('0') or '0'
+              return f"{major}.{minor}"
+
+          tuples = {}
+          for row in data.get('include', []):
+              if row.get('database') != 'pgsql':
+                  continue
+              moodle_branch = row.get('moodle-branch', '')
+              minor_branch = to_minor_branch(moodle_branch)
+              moodle_minor = branch_to_minor.get(minor_branch, '')
+              if not moodle_minor:
+                  # main does not have a stable 10-digit Moodle minor.
+                  continue
+
+              php = str(row.get('php', ''))
+              pgsql_ver = str(row.get('pgsql-ver', ''))
+              if not php or not pgsql_ver:
+                  continue
+
+              branch_slug = moodle_branch.replace('_', '-').lower()
+              image = 'ghcr.io/catalyst/catalyst-moodle-workflows-pgseed'
+              immutable_tag = f"{branch_slug}-php{php}-pg{pgsql_ver}-m{moodle_minor}"
+              mutable_tag = f"{branch_slug}-php{php}-pg{pgsql_ver}-latest"
+
+              key = (moodle_branch, php, pgsql_ver, moodle_minor)
+              tuples[key] = {
+                  'moodle-branch': moodle_branch,
+                  'php': php,
+                  'pgsql-ver': pgsql_ver,
+                  'moodle-minor': moodle_minor,
+                  'image': image,
+                  'immutable-tag': immutable_tag,
+                  'mutable-tag': mutable_tag,
+              }
+
+          matrix = sorted(tuples.values(), key=lambda x: (x['moodle-branch'], x['php'], x['pgsql-ver']))
+          with open(os.environ['GITHUB_OUTPUT'], 'a', encoding='utf-8') as out:
+              out.write(f"matrix={json.dumps({'include': matrix})}\n")
+        shell: python
+
+  build:
+    needs: build-matrix
+    runs-on: ubuntu-latest
+    permissions:
+      contents: read
+      packages: write
+    strategy:
+      fail-fast: false
+      matrix: ${{ fromJson(needs.build-matrix.outputs.matrix) }}
+    steps:
+      - name: Checkout repository
+        uses: actions/checkout@v4
+
+      - name: Log in to GHCR
+        uses: docker/login-action@v3
+        with:
+          registry: ghcr.io
+          username: ${{ github.actor }}
+          password: ${{ secrets.GITHUB_TOKEN }}
+
+      - name: Build pgseed image
+        run: |
+          docker build \
+            --build-arg MOODLE_BRANCH=${{ matrix['moodle-branch'] }} \
+            --build-arg MOODLE_MINOR=${{ matrix['moodle-minor'] }} \
+            --build-arg PHP_VERSION=${{ matrix.php }} \
+            --build-arg POSTGRES_VERSION=${{ matrix['pgsql-ver'] }} \
+            -t ${{ matrix.image }}:${{ matrix['immutable-tag'] }} \
+            -t ${{ matrix.image }}:${{ matrix['mutable-tag'] }} \
+            -f docker/pgseed/Dockerfile docker/pgseed
+
+      - name: Push pgseed image tags
+        run: |
+          docker push ${{ matrix.image }}:${{ matrix['immutable-tag'] }}
+          docker push ${{ matrix.image }}:${{ matrix['mutable-tag'] }}
diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index a5a4afd5..1ec54294 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -446,7 +446,7 @@ jobs:
     runs-on: 'ubuntu-latest'
     services:
       postgres:
-        image: "postgres:${{ matrix.pgsql-ver }}"
+        image: "${{ matrix.database == 'pgsql' && matrix['pgseed-image'] != '' && matrix['pgseed-image'] || format('postgres:{0}', matrix['pgsql-ver']) }}"
         env:
           POSTGRES_USER: 'postgres'
           POSTGRES_HOST_AUTH_METHOD: 'trust'
@@ -490,11 +490,29 @@ jobs:
           database: ${{ matrix.database }}
       - name: Run phpunit
         run: |
+          if [ "${MATRIX_DATABASE}" = "pgsql" ] && [ -n "${PGSEED_IMAGE}" ]; then
+            # Restore moodle sitedata from the pgseed postgres service container.
+            pgseed_container="$(docker ps --filter "name=postgres" --format '{{.ID}}' | head -n 1)"
+            if [ -n "$pgseed_container" ] && dataroot="$(php -r 'require "moodle/config.php"; if (empty($CFG->dataroot)) { exit(1); } echo $CFG->dataroot;' 2>/dev/null)"; then
+              if docker cp "$pgseed_container:/pgseed/moodledata.tar.gz" /tmp/moodledata.tar.gz 2>/dev/null; then
+                mkdir -p "$dataroot"
+                tar -xzf /tmp/moodledata.tar.gz -C "$dataroot" --strip-components=1
+              fi
+            fi
+          fi
+          if php moodle/public/admin/tool/phpunit/cli/util.php --help | grep -q -- '--upgrade'; then
+            php moodle/public/admin/tool/phpunit/cli/util.php --upgrade
+          else
+            echo "PHPUnit util upgrade mode not available on this Moodle branch; continuing with standard PHPUnit flow."
+          fi
           moodle-plugin-ci phpunit
           cd moodle
           vendor/bin/phpunit --fail-on-risky --disallow-test-output --filter tool_dataprivacy_metadata_registry_testcase
           vendor/bin/phpunit --fail-on-risky --disallow-test-output --testsuite core_privacy_testsuite --filter provider_testcase
         shell: bash
+        env:
+          MATRIX_DATABASE: ${{ matrix.database }}
+          PGSEED_IMAGE: ${{ matrix['pgseed-image'] }}
   behat:
     name: ${{ matrix.moodle-branch-short }} - behat - php${{ matrix.php }} - ${{ matrix.database }}
     needs: prepare_matrix
@@ -510,7 +528,7 @@ jobs:
     runs-on: 'ubuntu-latest'
     services:
       postgres:
-        image: "postgres:${{ matrix.pgsql-ver }}"
+        image: "${{ matrix.database == 'pgsql' && matrix['pgseed-image'] != '' && matrix['pgseed-image'] || format('postgres:{0}', matrix['pgsql-ver']) }}"
         env:
           POSTGRES_USER: 'postgres'
           POSTGRES_HOST_AUTH_METHOD: 'trust'
diff --git a/README.md b/README.md
index a2743676..6b5bf0c7 100644
--- a/README.md
+++ b/README.md
@@ -142,6 +142,17 @@ When you call the reusable ci, it will:
 
 To view or modify the full matrix, please see it here: [.github/actions/matrix/matrix_includes.yml](.github/actions/matrix/matrix_includes.yml)
 
+### Seeded PostgreSQL images
+
+PostgreSQL-backed CI jobs can use pre-built pgseed images published to GHCR:
+
+`ghcr.io/catalyst/catalyst-moodle-workflows-pgseed:<moodle-branch>-php<php>-pg<pgsql>-m<moodle-minor>`
+
+- `<moodle-minor>` is the Moodle 10-digit minor version from the Moodle updates API (same source used by matrix parsing).
+- Images are built by `.github/workflows/build-pgseed.yml` from `docker/pgseed/`.
+- Rebuild these images by running the `Build pgseed images` workflow manually, or by changing `docker/pgseed/**`, `.github/actions/matrix/matrix_includes.yml`, or `.github/workflows/build-pgseed.yml`.
+- CI applies the temporary MDL-88495 patch to the Moodle checkout (until merged upstream), runs `php public/admin/tool/phpunit/cli/util.php --upgrade` before phpunit, and restores sitedata from the pgseed postgres service container archive at `/pgseed/moodledata.tar.gz` (docker-level snapshot, no `util.php --restore` usage).
+
 ## How does this automate releases?
 
 Whenever a change is made to version.php, the workflow is triggered on a release branch (e.g. __main__ / __MOODLE_XX_STABLE__), and tests pass, will it attempt to run the plugin/release action `.github/plugin/release/action.yml`. Doing so will automatically publish a release to the Moodle plugin directory at https://moodle.org/plugins.
diff --git a/docker/pgseed/Dockerfile b/docker/pgseed/Dockerfile
new file mode 100644
index 00000000..020682ad
--- /dev/null
+++ b/docker/pgseed/Dockerfile
@@ -0,0 +1,26 @@
+ARG POSTGRES_VERSION=15
+FROM postgres:${POSTGRES_VERSION}
+
+ARG MOODLE_BRANCH
+ARG MOODLE_MINOR
+ARG PHP_VERSION
+ARG POSTGRES_VERSION
+
+ENV MOODLE_BRANCH=${MOODLE_BRANCH}
+ENV MOODLE_MINOR=${MOODLE_MINOR}
+ENV PHP_VERSION=${PHP_VERSION}
+ENV POSTGRES_VERSION=${POSTGRES_VERSION}
+
+LABEL org.opencontainers.image.source="https://github.com/catalyst/catalyst-moodle-workflows"
+LABEL org.opencontainers.image.description="Seeded PostgreSQL image for catalyst-moodle-workflows"
+LABEL org.catalyst.moodle.branch="${MOODLE_BRANCH}"
+LABEL org.catalyst.moodle.minor="${MOODLE_MINOR}"
+LABEL org.catalyst.php.version="${PHP_VERSION}"
+LABEL org.catalyst.pgsql.version="${POSTGRES_VERSION}"
+
+COPY seed.sh /docker-entrypoint-initdb.d/20-seed.sh
+COPY moodledata/ /opt/pgseed/moodledata/
+RUN chmod +x /docker-entrypoint-initdb.d/20-seed.sh
+RUN mkdir -p /pgseed \
+  && tar -C /opt/pgseed -czf /pgseed/moodledata.tar.gz moodledata \
+  && rm -rf /opt/pgseed
diff --git a/docker/pgseed/moodledata/.gitkeep b/docker/pgseed/moodledata/.gitkeep
new file mode 100644
index 00000000..e69de29b
diff --git a/docker/pgseed/seed.sh b/docker/pgseed/seed.sh
new file mode 100644
index 00000000..4534ae7c
--- /dev/null
+++ b/docker/pgseed/seed.sh
@@ -0,0 +1,32 @@
+#!/usr/bin/env bash
+set -euo pipefail
+
+MOODLE_BRANCH="${MOODLE_BRANCH:-unknown}"
+MOODLE_MINOR="${MOODLE_MINOR:-unknown}"
+PHP_VERSION="${PHP_VERSION:-unknown}"
+POSTGRES_VERSION="${POSTGRES_VERSION:-unknown}"
+
+psql -v ON_ERROR_STOP=1 --username "$POSTGRES_USER" <<-SQL
+  CREATE DATABASE moodle;
+SQL
+
+psql \
+  -v ON_ERROR_STOP=1 \
+  -v moodle_branch="$MOODLE_BRANCH" \
+  -v moodle_minor="$MOODLE_MINOR" \
+  -v php_version="$PHP_VERSION" \
+  -v pgsql_version="$POSTGRES_VERSION" \
+  --username "$POSTGRES_USER" \
+  --dbname moodle <<-'SQL'
+  CREATE SCHEMA IF NOT EXISTS ci_seed;
+  CREATE TABLE IF NOT EXISTS ci_seed.metadata (
+      id BIGSERIAL PRIMARY KEY,
+      moodle_branch TEXT NOT NULL,
+      moodle_minor TEXT NOT NULL,
+      php_version TEXT NOT NULL,
+      pgsql_version TEXT NOT NULL,
+      created_at TIMESTAMPTZ NOT NULL DEFAULT NOW()
+  );
+  INSERT INTO ci_seed.metadata (moodle_branch, moodle_minor, php_version, pgsql_version)
+  VALUES (:'moodle_branch', :'moodle_minor', :'php_version', :'pgsql_version');
+SQL