Ask HN: Good resources for slow test suites in RoR applications

For a while now I’ve been trying to think of creative ways to improve the test suite of a rather large Ruby on Rails application.

The CI/CD pipeline for this test suite constantly has flaky tests and can take on average 1hr to run.

I can’t think of any good places to start other than using a test profiler.

Does anyone have experience with this journey or similar?