Test the upgrade flow.
Without burning real cards.

Stripe checkout regression FAQ

How do I test a Stripe checkout flow without burning real cards?

Use Stripe test mode (test API keys + the 4242 4242 4242 4242 card) and record the full upgrade flow in Lastest once. Lastest emits Playwright code that replays the flow deterministically: sign in, click upgrade, enter the test card, submit, assert the success page renders and the post-checkout app state updated. Zero real charges, zero tokens per run.

Does Lastest test the redirect back to my app after Stripe Checkout?

Yes. The recording follows the redirect from checkout.stripe.com back to your success URL and asserts the resulting page. If your success URL parses the session_id wrong, fails to call your fulfillment endpoint, or the app shows a stale plan, the visual diff catches it. Real end-to-end coverage, not just “Stripe redirected.”

Can it test webhooks too?

Lastest tests the running app, so webhooks are tested implicitly: after the test card succeeds, your app eventually flips the user’s plan via the webhook. The recording asserts that flipped state, the “Pro” badge on the dashboard, the new feature unlocked. If the webhook never fires or your handler crashes, the assertion fails. For unit-level webhook testing, pair Lastest with Stripe CLI listen.

What about Stripe Checkout vs. Stripe Elements / Payment Element?

Both work. Stripe Checkout takes you to a hosted page (checkout.stripe.com); the Payment Element keeps the card form on your domain. Lastest records the click stream either way: for Elements, the iframed card field types into the test card directly; for Checkout, the recorder follows the cross-origin redirect back to your success URL.

How do I keep the test stable when Stripe redesigns checkout.stripe.com?

Stripe owns that page; you don’t. Lastest’s seven-layer selector fallback (data-testid, id, role, aria-label, text, CSS, OCR) survives most cosmetic redesigns of Stripe-hosted pages. When it doesn’t, the visual diff at your success URL still catches the regression, since that’s the page you actually own.

Can it run on every PR in CI?

Yes. Use the GitHub Action (las-team/lastest/action@main) against your PR preview URL, with Stripe in test mode and a long-lived test customer. The full upgrade flow runs in under a minute and fails the PR on a non-trivial diff. Approved baselines replay deterministically with $0 token cost forever.

What does this cost?

Zero. Lastest is open source (FSL-1.1-ALv2), self-hosted via Docker. Generate the checkout-flow tests once, replay on every push for $0. No per-screenshot, no per-seat, no token cost on replay. Stripe test mode is also free.