Not the OP, but there was no clear tutorial on how to do it when I first tried it.

I've got actual work to do, I don't have time to spend a day or two figuring out how to do yarn2 on our dev machines + CI env + prod. So we just stuck with yarn1.

Now when Yarn 3 is out, it's either back to npm, which is supposedly on par with yarn1 in speed or I'll try a yarn 1 ->3 transition.

Not that I’m a fan of Yarn 2+, but this view strikes me as narrow. Setting up and upgrading the development environment is actual work, too! If you don’t treat it as such, developer efficiency will suffer in the long run.

But breaking the development and CI environments will prevent a good dozen people from working. So it's a risk vs reward question.

Unless it’s some arcane setup, I don’t see what would break from one developer trying stuff on a branch.

Even if you don’t have your build pipelines in the same or any repo, you could probably clone then modify them on a reasonable CI server.