Ruby is not really slowing us down, the bigger issue is that we have a lot of integration tests and few isolated unit tests. So we are massively parallelizing our builds so we can get p50 build times of 23 minutes when running the whole test suite. The time mentioned in the article is a little bit closer to the p95 time.

> If there’s an intensity of flakiness that can withstand the gaze of a couple hundred engineers for more than an hour or so, we haven’t found one yet.

That is a good approach and we also used to disable tests that would fail on full master builds. When it comes to fixing intermittently failing tests we are now storing every test run so we can analyze our test suite. This way we are able to find the slowest and flakiest tests in the codebase, disable them, and notify the owners of the code to investigate.