For teams with a test that passes and fails with no code change, and no time to find out why.

Your setup

Say this to Certyn

The "apply coupon" test in acme/web is flaky. Find out why and fix it in a PR.

Opens the GH_TOKEN form if needed: Contents and Pull requests, Read and write.
Clones the repo and runs the test many times in a row against the environment (for Playwright, --repeat-each), with the same settings as your CI.
Compares passing and failing tries: traces, screenshots, timing, test data, test order.
Names the cause, for example a click before the page is ready, data shared between tests, or a fixed wait.
Makes the smallest fix on a certyn/... branch, such as waiting for the right element or giving the test its own data.
Runs it many times again and opens a pull request with the cause, the fix, and the before and after pass counts.

One pull request with the fix and the proof.
If the app is at fault (for example a button that sometimes submits twice), a Certyn issue with evidence, not a test change.

Certyn never makes a test pass by weakening it: no removed checks, no retries added to hide the failure, no larger timeouts as the only fix.
Some flakes appear only under CI load. If Certyn cannot make the test fail in many tries, it says so and does not guess a fix. Share a CI trace or run it on your self-hosted runner.
One shell command on a Machine can run 30 minutes. Longer repeat loops run in the background, or as a run of up to 4 hours.