Checkout blocked for segment: pre-release and first 30 minutes checklists

A checkout step fails for one customer segment, country or card type after a release.

The pre-release checklist maps each item to a test class from the incident page. The first-30-minutes checklist covers detection, containment, the rollback decision and customer communication.

7 pre-release items · 7 first-30-minutes items · verified 2026-10-21

Pre-release checklist

PR-01Add validator unit cases for a four-digit Argentine postcode such as 1213 and run them on every bump of the postcode validation package. unit
PR-02Add a unit case for each country that has no entry in the shared postcode rules file and therefore falls back to the validation package. unit
PR-03Run the client-side validator unit tests with one server-accepted sample postcode per country. unit
PR-04Run the checkout flow end to end with one saved address per shipping country, including an Argentine address with a four-digit postcode. e2e
PR-05Place an end-to-end test payment through the temporary (CSE) token workflow before switching the gateway integration version. e2e
PR-06Add a canary alert on the 4xx rate of payment requests alongside the 5xx alert. canary
PR-07Split canary payment error rates by gateway token workflow before promoting a gateway integration change. canary

First 30 minutes

FM-01Break down failed checkout attempts since the release by shipping country and by payment token workflow.
FM-02Read the 4xx rate on payment requests directly, because 5xx alerts stay silent for this failure.
FM-03Reproduce the failure in production with an address or payment method from the affected segment.
FM-04Revert the gateway integration change or pin the postcode validation package to its previous version, whichever the breakdown points to.
FM-05Give merchants and support staff the interim workaround, such as staying on the previous release, until the fix ships.
FM-06Post a status update that names the affected country or payment workflow.
FM-07Export the orders and payments that failed during the window so support can contact those customers.

Download the checklist

Pre-release checklist (Markdown)1.4 KB · v1.0.0
First 30 minutes checklist (Markdown)1.1 KB · v1.0.0

Only in this checklist

PR-04 is the only item among 4 published checklists in this group that relies on end-to-end tests: Run the checkout flow end to end with one saved address per shipping country, including an Argentine address with a four-digit postcode.

Questions

What should be checked before a release to prevent Checkout blocked for segment?

7 pre-release items, PR-01 to PR-07. PR-01: Add validator unit cases for a four-digit Argentine postcode such as 1213 and run them on every bump of the postcode validation package.

Is there a rollback plan for Checkout blocked for segment?

The first-30-minutes checklist has 7 items. FM-01: Break down failed checkout attempts since the release by shipping country and by payment token workflow.

What should a team do in the first 30 minutes after Checkout blocked for segment is detected?

The first-30-minutes checklist has 7 items. FM-01: Break down failed checkout attempts since the release by shipping country and by payment token workflow.

Is a Checkout blocked for segment checklist still needed if deployment is automated?

Yes. Automation runs the steps; the checklist names what the tests must cover: unit tests, end-to-end tests and canary and progressive delivery checks.

Which pipeline stages does the Checkout blocked for segment checklist cover?

The pre-release items map to the pre-merge, pre-deploy and post-deploy stages.

In what formats can the Checkout blocked for segment checklist be downloaded?

Both checklists download as Markdown files: /downloads/checkout-blocked-for-segment-pre-release.md and /downloads/checkout-blocked-for-segment-first-30-minutes.md, licensed CC BY 4.0.