Cargo-mutants:zombie: Inject bugs and see if your tests catch them

Really cool! I wish there was such a thing for JavaScript.

I say this as a so-so software engineer. I badly wish there was more emphasis on increasing software quality. There is so much the industry could do to radically improve quality, such as tools like this.

I know the incentives just aren't there, but still.

Good news it is a thing in js!

https://stryker-mutator.io/

There was some hype about it some years ago.

There is such a thing. Basically every popular language has a mutation-testing frameworks. It's pretty common for large scale projects.