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kotlinlang

I'm trying to parallelize our (Maven) build, and as CPU load goes to 100% I have quite a few tests failing for various reasons (e.g. testcontainers startup times out, some tests use `Instant.now()` etc.).
I'm currently fixing these one by one, but it's hard to always reproduce the errors (and therefore to be sure I really fixed it).

Is there some library or framework to slow down test execution _reproducibly_, to find such errors?

It's not what you asked for and it may not even help, but I find that I can at least shake the 'flake tree' if I modify the number of forks used whilst executing tests.

Often in my gradle configuration I'll have something that sets the `maxForks = Runtime.cpuCount() / 2 + 1` or something like that and if I copy the number that is generated by that _scientific_ process on the CI machine, I often get lucky locally to get semi consistent reproduction of CI test failures.

Of course, it's not a science, just a kind of shaman voodoo magic.