Get unstuck

Hint 1: Verification is a precondition

verified tells you the cryptographic verifier succeeded; it does not select an authorized producer.

Hint 2: Match every policy field

Use the policy’s immutable artifact and source identifiers, not labels from a UI.

Reveal the reference patch and explanation
Fixedrelease-policy.mjsJavaScript
export function allowRelease(evidence, policy) {
  return evidence.verified === true
    && ['digest','repository','workflow','ref','sourceCommit']
      .every(field => evidence[field] === policy[field]);
}

verified=true is necessary but insufficient. The allowed release also matches sha256:release-A, repository acme/invoices, workflow release.yml, ref refs/tags/v1 and sourceCommit commit-A. Changing any one field yields false, even if the verifier authenticated the statement. The string "true" is rejected because it is not the verifier’s boolean result. Once this gate allows the release, deployment must still use that verified digest; pulling a mutable tag later would create a new artifact-selection decision.

Compare it with your own fix, then rerun the tests. The editor is not changed when you open this explanation.

Inspect the actual test harness

The browser and the lab download run the same cases, including cases that catch common wrong fixes, such as comparing with one fixture value instead of the real rule. The download includes the complete test adapter and cryptographic fixtures.

Download cases.mjs
How the browser sandbox runs your code

Your code runs in QuickJS 2025-09-13 (quickjs-emscripten 0.32.0) inside a Web Worker, isolated from the page, with a 32 MiB memory limit and a 2.5-second time limit. The test cases and the pass or fail verdict run outside that sandbox, so changing built-ins such as Array.prototype.push cannot change the result. The lab download runs the same cases under Node.js, where your code runs directly.

The same as in current Node.js:

  • ES2025 syntax and built-ins, including Set methods such as intersection, iterator helpers, Promise.try, RegExp.escape and the RegExp v flag

Added to the sandbox so that it behaves like Node.js:

  • structuredClone, Array.fromAsync, queueMicrotask, atob and btoa
  • URL and URLSearchParams, parsed by your browser’s own URL implementation
  • TextEncoder and TextDecoder for UTF-8
  • Intl.Collator and a locale-aware String.prototype.localeCompare
  • console.log and related methods, whose output appears with your results

Not available in the browser sandbox:

  • Timers (setTimeout, setInterval), fetch and other network or storage APIs; the exercises are deterministic and offline
  • Node.js modules and globals: import, require, process and Buffer
  • Web Crypto (crypto.getRandomValues, crypto.subtle); each workshop supplies the cryptographic operations it needs
  • Intl other than Collator: toLocaleString and toLocaleDateString ignore the locale, so numbers have no digit grouping and dates use one fixed format in the device’s time zone
  • using declarations, Symbol.dispose and DisposableStack (explicit resource management)
  • Uint8Array.fromBase64 and toBase64, JSON.rawJSON, Atomics and Error.captureStackTrace

Use the lesson in your own system

The exercise tests policy on trusted verifier output; it does not implement signature verification. Use a maintained verifier with the expected issuer/identity, trust roots and transparency policy. A client cannot self-assert verified=true.

Your next task: Where is verifier output bound to the artifact that your deployment system actually pulls?

Sigstore verification

Related guide: Verify artifact signatures against an explicit trust policy