Swift’s powerful type system empowers us to create semantically explicit and safe data models. Yet when we move to SwiftData or Core Data, the constraints of their underlying storage mechanisms often force us to compromise on type expressiveness. Those concessions blur our domain models’ intent and plant hidden seeds of instability.

This article explores how, within the restrictions of persistence layers, we can leverage ingenious type wrappers and conversions to build data models that are simultaneously Type-safe, semantically clear, and highly efficient.