Sure. You tend to think about the edges of your application.
1. Router
Tanstack Router: Supports runtime validation libraries such as z0d. So I have routes such as example.com/viewer/$uuid/$number, it should 400 if those aren't actually validate uuid and numbers.
React Router: Supports Types, but every type is a string because, well, they technically are, but this isn't useful in practice in my opinion. There are 3rd party libs such as: https://github.com/fenok/react-router-typesafe-routes
2. API
Lets say you're making your API public to clients you can't trust to send the correct data ( which probably also includes your own client ).
