diff --git a/.github/workflows/quality-links.yml b/.github/workflows/quality-links.yml
new file mode 100644
index 00000000..cfe6f5a8
--- /dev/null
+++ b/.github/workflows/quality-links.yml
@@ -0,0 +1,130 @@
+name: Quality Ledger - Link Integrity
+
+on:
+  push:
+    tags:
+      - 'v*'
+  workflow_dispatch:
+    inputs:
+      version:
+        description: 'Version to record (defaults to tag name or VERSION.txt)'
+        required: false
+      ref:
+        description: 'Git ref to scan (defaults to tag ref or main)'
+        required: false
+
+permissions:
+  contents: write
+
+jobs:
+  broken-link-metrics:
+    runs-on: ubuntu-latest
+    steps:
+      - name: Determine scan ref and version
+        id: meta
+        env:
+          REF_INPUT: ${{ github.event.inputs.ref || '' }}
+          VERSION_INPUT: ${{ github.event.inputs.version || '' }}
+          EVENT_NAME: ${{ github.event_name }}
+          GITHUB_REF_VALUE: ${{ github.ref }}
+          GITHUB_REF_NAME_VALUE: ${{ github.ref_name }}
+        run: |
+          if [ -n "$REF_INPUT" ]; then
+            SCAN_REF="$REF_INPUT"
+          elif [ "$EVENT_NAME" = "push" ]; then
+            SCAN_REF="$GITHUB_REF_VALUE"
+          else
+            SCAN_REF="main"
+          fi
+
+          if [ -n "$VERSION_INPUT" ]; then
+            VERSION="$VERSION_INPUT"
+          elif [[ "$GITHUB_REF_VALUE" == refs/tags/v* ]]; then
+            VERSION="$GITHUB_REF_NAME_VALUE"
+          else
+            VERSION=""
+          fi
+
+          echo "scan_ref=$SCAN_REF" >> "$GITHUB_OUTPUT"
+          echo "version=$VERSION" >> "$GITHUB_OUTPUT"
+
+      - name: Checkout scan ref
+        uses: actions/checkout@v4
+        with:
+          token: ${{ secrets.GITHUB_TOKEN }}
+          fetch-depth: 0
+          ref: ${{ steps.meta.outputs.scan_ref }}
+
+      - name: Resolve version from VERSION.txt when needed
+        id: resolved_version
+        run: |
+          VERSION="${{ steps.meta.outputs.version }}"
+          if [ -z "$VERSION" ]; then
+            VERSION="v$(cat _includes/VERSION.txt)"
+          fi
+          echo "version=$VERSION" >> "$GITHUB_OUTPUT"
+
+      - name: Setup Ruby
+        uses: ruby/setup-ruby@v1
+        with:
+          ruby-version: '3.2'
+          bundler-cache: true
+
+      - name: Build site
+        run: bundle exec jekyll build --verbose
+
+      - name: Run linkinator (internal links only)
+        id: linkinator
+        run: |
+          python3 -m http.server 4001 --bind 127.0.0.1 --directory _site >/tmp/quality-links-server.log 2>&1 &
+          SERVER_PID=$!
+          trap "kill $SERVER_PID" EXIT
+
+          set +e
+          npx --yes linkinator http://127.0.0.1:4001 --recurse --format json --verbosity error --skip '^https?://(?!127\.0\.0\.1:4001)' --skip '^//' > /tmp/linkinator-results.json
+          set -e
+
+          BROKEN_COUNT=$(node -e "const fs=require('fs'); const p='/tmp/linkinator-results.json'; const raw=fs.readFileSync(p,'utf8'); const data=JSON.parse(raw); const links=Array.isArray(data.links)?data.links:[]; process.stdout.write(String(links.filter((l)=>l.state==='BROKEN').length));")
+          echo "broken_count=$BROKEN_COUNT" >> "$GITHUB_OUTPUT"
+          echo "Broken links found: $BROKEN_COUNT"
+          cat /tmp/linkinator-results.json
+
+      - name: Checkout main for quality log persistence
+        run: |
+          git fetch origin main
+          git switch main
+
+      - name: Append quality log entry
+        env:
+          VERSION: ${{ steps.resolved_version.outputs.version }}
+          BROKEN_COUNT: ${{ steps.linkinator.outputs.broken_count }}
+          COMMIT_SHA: ${{ github.sha }}
+          WORKFLOW_RUN_URL: ${{ github.server_url }}/${{ github.repository }}/actions/runs/${{ github.run_id }}
+        run: |
+          ruby tools/append_quality_log.rb \
+            --version "$VERSION" \
+            --broken-links "$BROKEN_COUNT" \
+            --commit-sha "$COMMIT_SHA" \
+            --workflow-run-url "$WORKFLOW_RUN_URL" \
+            --output _data/quality_log.yml
+
+      - name: Fail when broken links are present
+        if: steps.linkinator.outputs.broken_count != '0'
+        run: |
+          echo "::error::Broken link scan found ${{ steps.linkinator.outputs.broken_count }} broken link(s)."
+          exit 1
+
+      - name: Commit quality log update
+        if: always()
+        env:
+          VERSION: ${{ steps.resolved_version.outputs.version }}
+        run: |
+          git config user.name "github-actions[bot]"
+          git config user.email "github-actions[bot]@users.noreply.github.com"
+          git add _data/quality_log.yml
+          if git diff --staged --quiet; then
+            echo "No quality log changes to commit"
+          else
+            git commit -m "chore: log link integrity for ${VERSION}"
+            git push origin main
+          fi
diff --git a/_data/quality_log.yml b/_data/quality_log.yml
new file mode 100644
index 00000000..fe51488c
--- /dev/null
+++ b/_data/quality_log.yml
@@ -0,0 +1 @@
+[]
diff --git a/test/append_quality_log_test.rb b/test/append_quality_log_test.rb
new file mode 100644
index 00000000..5082b6f9
--- /dev/null
+++ b/test/append_quality_log_test.rb
@@ -0,0 +1,53 @@
+#!/usr/bin/env ruby
+# frozen_string_literal: true
+
+require 'minitest/autorun'
+require 'open3'
+require 'tmpdir'
+require 'yaml'
+
+ROOT = File.expand_path('..', __dir__)
+APPENDER = File.join(ROOT, 'tools', 'append_quality_log.rb')
+
+class AppendQualityLogTest < Minitest::Test
+  def test_appends_new_entry_to_existing_log
+    Dir.mktmpdir do |dir|
+      output = File.join(dir, 'quality_log.yml')
+      File.write(output, [{ 'version' => 'v1', 'broken_links' => 0 }].to_yaml)
+
+      _stdout, stderr, status = Open3.capture3(
+        'ruby', APPENDER,
+        '--version', 'v2',
+        '--broken-links', '3',
+        '--commit-sha', 'abc123',
+        '--workflow-run-url', 'https://example.com/run/1',
+        '--release-date', '2026-09-07T00:00:00Z',
+        '--output', output
+      )
+
+      assert status.success?, "expected success, got stderr:\n#{stderr}"
+
+      log = YAML.safe_load_file(output)
+      assert_equal 2, log.length
+      assert_equal 'v2', log.last['version']
+      assert_equal 3, log.last['broken_links']
+      assert_equal 'abc123', log.last['commit_sha']
+      assert_equal 'https://example.com/run/1', log.last['workflow_run_url']
+      assert_equal(
+        { 'performance' => nil, 'accessibility' => nil, 'seo' => nil },
+        log.last['lighthouse']
+      )
+    end
+  end
+
+  def test_rejects_negative_broken_link_count
+    _stdout, stderr, status = Open3.capture3(
+      'ruby', APPENDER,
+      '--version', 'v2',
+      '--broken-links', '-1'
+    )
+
+    refute status.success?
+    assert_match(/--broken-links must be >= 0/, stderr)
+  end
+end
diff --git a/tools/append_quality_log.rb b/tools/append_quality_log.rb
new file mode 100644
index 00000000..2bf9452a
--- /dev/null
+++ b/tools/append_quality_log.rb
@@ -0,0 +1,51 @@
+#!/usr/bin/env ruby
+# frozen_string_literal: true
+
+require 'optparse'
+require 'yaml'
+require 'time'
+
+options = {
+  output: '_data/quality_log.yml',
+  release_date: Time.now.utc.iso8601
+}
+
+OptionParser.new do |opts|
+  opts.banner = 'Usage: ruby tools/append_quality_log.rb --version v123 --broken-links 0 [options]'
+
+  opts.on('--version VERSION', 'Release version (for example: v123)') { |v| options[:version] = v }
+  opts.on('--broken-links COUNT', Integer, 'Broken link count') { |v| options[:broken_links] = v }
+  opts.on('--commit-sha SHA', 'Commit SHA for this snapshot') { |v| options[:commit_sha] = v }
+  opts.on('--workflow-run-url URL', 'Workflow run URL') { |v| options[:workflow_run_url] = v }
+  opts.on('--release-date DATE', 'Release date (ISO 8601)') { |v| options[:release_date] = v }
+  opts.on('--output PATH', 'Output YAML path') { |v| options[:output] = v }
+end.parse!
+
+abort('Missing required --version') unless options[:version]
+abort('Missing required --broken-links') unless options.key?(:broken_links)
+abort('--broken-links must be >= 0') if options[:broken_links].negative?
+
+log_entries =
+  if File.exist?(options[:output])
+    data = YAML.safe_load_file(options[:output], permitted_classes: [Time], aliases: false)
+    data.is_a?(Array) ? data : []
+  else
+    []
+  end
+
+log_entries << {
+  'version' => options[:version],
+  'release_date' => options[:release_date],
+  'commit_sha' => options[:commit_sha],
+  'lighthouse' => {
+    'performance' => nil,
+    'accessibility' => nil,
+    'seo' => nil
+  },
+  'broken_links' => options[:broken_links],
+  'build_time_seconds' => nil,
+  'workflow_run_url' => options[:workflow_run_url]
+}
+
+File.write(options[:output], log_entries.to_yaml)
+puts "Appended quality log entry for #{options[:version]} with #{options[:broken_links]} broken link(s)."