I use zod but it's a workaround. I use non standard syntax to define types.

If typescript emitted type information, we'd be able to automatically get runtime validation at the boundaries of our apps.

Alternatively, io-ts is more performant and has been around for a while longer. Although it does have a more functional interface.

I like typia for doing codegen basically in the way this request is asking: it hooks into the typescript API to create runtypes from plain old typescript