So you launch and the you add (dependent) types. That works and is quite a good way imho: when you start writing you miss a lot of details so you want to freely

So you launch and the you add (dependent) types. That works and is quite a good way imho: when you start writing you miss a lot of details so you want to freely experiment and when parts get clearer and become stable you can rewrite, reactor, add types and proofs.