feat(ci): harden the supply chain and build the server once

.github/workflows/ci-security-scan.yml

@@ -15,6 +15,25 @@ on:
         default: "false"
 
 jobs:
+  dependency-review:
+    name: "New dependency risk"
+    runs-on: ubuntu-latest
+    if: inputs.should_skip != 'true' && github.event_name == 'pull_request'
+    timeout-minutes: 5
+    permissions:
+      contents: read
+    steps:
+      # Use GitHub's dependency graph instead of rescanning the whole lockfile diff ourselves. This
+      # blocks newly introduced fixable risk without wedging unrelated PRs on existing findings;
+      # Renovate and the scheduled image rescans own remediation of the existing baseline.
+      - name: Review dependency changes
+        uses: actions/dependency-review-action@a1d282b36b6f3519aa1f3fc636f609c47dddb294 # v5.0.0
+        with:
+          fail-on-severity: high
+          license-check: true
+          vulnerability-check: true
+          show-openssf-scorecard: true
+
   security-scan:
     name: "Dependencies, secrets, and policy"
     runs-on: ubuntu-latest

.github/workflows/scorecard.yml

@@ -0,0 +1,47 @@
+name: OpenSSF Scorecard
+
+# Repository posture changes independently of a code diff. Keep this off the pull-request critical
+# path and rescan the default branch weekly; a push catches workflow and policy changes immediately.
+on:
+  schedule:
+    - cron: "23 4 * * 1"
+  push:
+    branches: ["main"]
+
+concurrency:
+  group: ${{ github.workflow }}-${{ github.ref }}
+  cancel-in-progress: true
+
+permissions: read-all
+
+jobs:
+  analysis:
+    name: Supply-chain posture
+    runs-on: ubuntu-latest
+    timeout-minutes: 10
+    permissions:
+      contents: read
+      id-token: write
+      security-events: write
+    steps:
+      - name: Run OpenSSF Scorecard
+        uses: ossf/scorecard-action@2d1146689b8cda280b9bc96326124645441f03bc # v2.4.4
+        with:
+          results_file: results.sarif
+          results_format: sarif
+          publish_results: true
+
+      - name: Upload findings to code scanning
+        if: always()
+        uses: github/codeql-action/upload-sarif@cdf488f595d80d6e07e03d4674febd5ab45fa938 # v4.37.9
+        with:
+          sarif_file: results.sarif
+
+      - name: Preserve the assessment
+        if: always()
+        uses: actions/upload-artifact@043fb46d1a93c77aae656e7c1c64a875d1fc6a0a # v7.0.1
+        with:
+          name: openssf-scorecard-${{ github.sha }}
+          path: results.sarif
+          if-no-files-found: error
+          retention-days: 14

docs/contributor/ci-cd.mdx

@@ -396,6 +396,33 @@ commands.
 
 ## 📊 CI Features
 
+### Supply-chain feedback
+
+Supply-chain checks run at the point where their result is actionable rather than making every
+scanner part of every pull request:
+
+- Pull requests use GitHub's
+  [dependency review](https://docs.github.com/code-security/supply-chain-security/understanding-your-software-supply-chain/about-dependency-review)
+  to reject newly introduced high or critical vulnerabilities and report dependency-license
+  changes. This is a diff gate: existing findings remain visible without preventing an unrelated
+  fix from merging.
+- Trivy scans the repository dependency baseline in the required Security leg and publishes SARIF
+  to code scanning. Image builds additionally evaluate the documented vulnerability policy against
+  the image that was actually produced; weekly rescans detect vulnerability-database drift after a
+  clean merge.
+- [OpenSSF Scorecard](https://securityscorecards.dev/) evaluates repository and workflow posture on
+  every push to `main` and weekly (which also catches settings-only drift). It publishes authenticated
+  results and SARIF without adding another network scanner to the pull-request critical path.
+- CodeQL remains enabled through GitHub default setup. GitHub's
+  [recommended configuration](https://docs.github.com/code-security/code-scanning/enabling-code-scanning/configuring-default-setup-for-code-scanning)
+  owns language discovery and query updates rather than a second workflow duplicating them.
+
+The checks deliberately answer different questions: dependency review prevents a regression,
+Trivy inventories current package and image exposure, CodeQL finds source-level data-flow defects,
+and Scorecard measures the repository controls that make the resulting artifacts trustworthy.
+Release images remain digest-bound, signed, SBOM-attested, provenance-attested, and verified as
+described in [Release management](./release-management.mdx#supply-chain-evidence).
+
 ### Test Results
 
 All test suites generate JUnit XML reports that are displayed in the **Test Results** tab of each workflow run:

scripts/ci-contract.test.ts

@@ -369,6 +369,26 @@ void describe("CI contract", () => {
 		}
 	});
 
+	void test("reviews dependency diffs and measures repository supply-chain posture", async () => {
+		const security = await readFile(".github/workflows/ci-security-scan.yml", "utf8");
+		const dependencyReview = job(security, "dependency-review");
+		assert.match(dependencyReview, /github\.event_name == 'pull_request'/);
+		assert.match(dependencyReview, /actions\/dependency-review-action@[a-f0-9]{40}/);
+		assert.match(dependencyReview, /fail-on-severity: high/);
+		assert.match(dependencyReview, /license-check: true/);
+		assert.match(dependencyReview, /vulnerability-check: true/);
+
+		const scorecard = await readFile(".github/workflows/scorecard.yml", "utf8");
+		assert.match(scorecard, /^ {2}schedule:/m);
+		assert.match(scorecard, /^ {2}push:\n {4}branches: \["main"\]/m);
+		assert.doesNotMatch(scorecard, /^ {2}pull_request:/m);
+		assert.match(scorecard, /ossf\/scorecard-action@[a-f0-9]{40}/);
+		assert.match(scorecard, /publish_results: true/);
+		assert.match(scorecard, /github\/codeql-action\/upload-sarif@[a-f0-9]{40}/);
+		assert.match(scorecard, /security-events: write/);
+		assert.match(scorecard, /id-token: write/);
+	});
+
 	void test("pins every external action to a full commit SHA with a version comment", async () => {
 		const invalid: string[] = [];
 		const files = await Array.fromAsync(glob(".github/{actions,workflows}/**/*.{yml,yaml}"));