I really like the idea of mutation testing, but I've never found a situation where I've got it to work well. Either the project just didn't have the test support needed to make it work, or the mutation toolkit wasn't mature enough, or it didn't work with the specific tools I was already using. When you suggested it, I had a go again with a project I'm working on using Vitest and Striker, but unfortunately Striker just doesn't work with Vitest yet.

I'd definitely love to use it more though, it's one of those things I come back to every so often, unfortunately thus far without much success.