Jetpack Navigation 3 Migration: Type-Safe Routes & Nav2

A developer documents their experience migrating a production Android app with 40+ screens from Navigation 2 to Navigation 3. Nav3 introduces type-safe data class routes, developer-owned back stacks via SnapshotStateList, and compile-time argument safety—eliminating Nav2's string-based routing and runtime crashes. However, the migration reveals undocumented gaps around shared ViewModels, deep links, and inter-screen result passing that required custom workarounds.