Swift Actors for Thread-Safe Persistence

Patterns for building thread-safe data persistence layers using Swift actors. Combines in-memory caching with file-backed storage, leveraging the actor model to eliminate data races at compile time.

When to Activate

• Building a data persistence layer in Swift 5.5+
• Need thread-safe access to shared mutable state
• Want to eliminate manual synchronization (locks, DispatchQueues)
• Building offline-first apps with local storage

Core Pattern

Actor-Based Repository

The actor model guarantees serialized access — no data races, enforced by the compiler.