[Tyriar]

Const enums specifically are great, since they disappear on compile you can use them to internally document strings/numbers with verbose names/comments without the cost of a const variable that would appear after compilation.

As for the fact that types cannot simply be stripped out, I've found building using plain tsc and have the bundler target tsc's output directory. This separation is needed since most tools don't support TypeScript project references anyway which I find extremely useful for organizing internal modules.