swift-actor-persistence

Thread-safe data persistence in Swift using actors with in-memory cache and file-backed storage. 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. The actor model guarantees serialized access — no data races, enforced by the compiler. All calls are automatically async due to actor isolation: - Implements an actor-based repository pattern that eliminates data races at compile time, replacing manual synchronization with Swift's actor model - Combines fast O(1) in-memory lookups with atomic file persistence, supporting any Codable & Identifiable model type - Provides synchronous initialization to avoid async complexity, with automatic await enforcement on all public API calls - Designed for offline-first apps, local user data storage, and concurrent access patterns in iOS/macOS applications - 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 - Use Sendable types for all data crossing actor boundaries - Keep the actor's public API minimal — only expose domain operations, not persistence details - Use .atomic writes to prevent data corruption if the app crashes mid-write -...