This is an unsolicited endorsement of "yup," an absolutely fantastic tool for validating input in all JavaScript and TypeScript applications.

I'm impressed by how well it meets my needs as a JavaScript developer while also, apparently, having absolutely ferocious TypeScript support for those who want to go all in on that.

Also an endorsement of @gregvanbrug for bringing it into my professional life.

I use yup in everything now. It's the new extra virgin olive oil.

https://github.com/jquense/yup