If your type-checker is “mature" enough to encode the full value level semantics of the code it types (rendering the code itself superfluous, as then you’d just

If your type-checker is “mature" enough to encode the full value level semantics of the code it types (rendering the code itself superfluous, as then you’d just need to compile the type-level code to get your app), you then have the problem of validating the logic of the type-level code, and the natural solution to that problem is, again, testing.