[skybrian]

Used properly, runtime checking and types go well together. Types help you remember whether incoming data has been validated. You can use them to make sure your code does runtime checking exactly once, rather than multiple times or not at all due to changes in different packages that can introduce security bugs. This can make security reviews a lot easier.

I don't know if that's commonly done in Typescript, though? It seems more common in web apps to trust your own server to send you good data.