Yes, we have a Selenium-based UI test suite at Mixpanel that's overall quite stable and runs all tests across several browsers. It tests strictly the front-end

Yes, we have a Selenium-based UI test suite at Mixpanel that's overall quite stable and runs all tests across several browsers. It tests strictly the front-end code, with API calls stubbed out, which is the biggest factor in maintaining fast deterministic tests. By way of contrast we have an older end-to-end Selenium suite that spins up the entire service cluster, and that is the usual flaming pile of slow flakiness associated with Selenium. One of our engineers did a writeup on it a few years ago (now somewhat outdated but the overall picture is still accurate): https://engineering.mixpanel.com/2018/10/31/the-state-of-ui-testing-at-mixpanel/ https://engineering.mixpanel.com/2018/10/31/the-state-of-ui-...