[eropple]

1. You can deal with this with stuff like io-ts or runtypes. I strongly recommend either, though I use runtypes myself. Defining your objects in runtypes and having it implicitly return types for use elsewhere in your application is awesome, and it even works with branded types.

2. Yes and no. It's not the fastest build out there but if you've enabled incremental builds it's quite quick unless you're touching heavily related-to code (libraries that are imported all over the place). If that's not fast enough for you, I've seen people having very good success with `swc`.

3. I can't speak to webpack, but ts-node shouldn't be caching anything last I looked at it.