swift-concurrency-expert

Fix Swift concurrency data race warnings by identifying isolation violations and applying minimal safe changes like adding Sendable conformance or annotating types with @MainActor. Remediate actor isolation errors by reviewing compiler diagnostics and migrating unsafe code to comply with Swift 6.2+ concurrency requirements.

The best way to migrate completion handlers to async/await is by replacing callback signatures with async functions and applying minimal, verifiable changes to preserve behavior. This migration resolves compiler diagnostics and ensures safe concurrency by eliminating nested closure patterns.

Swift requires Sendable conformance for types crossing actor boundaries to prevent data races by guaranteeing safe value passing between concurrent execution contexts. Implementing Sendable ensures types are safely transferable across actors without introducing memory-level isolation violations.

Resolve UI-bound code actor isolation warnings by applying the @MainActor annotation to ensure UI updates execute on the main thread. This fixes isolation violations and maintains correctness across background tasks and UI interactions in Swift 6.2+ codebases.

Yes, this approach applies to Swift 6.2+ codebases with existing completion handlers by migrating them to async/await. It triages exact concurrency errors and applies minimal safe fixes to satisfy Sendable and actor-isolation requirements without breaking existing functionality.

Fixing Swift concurrency issues with @MainActor is limited to UI-bound or main-thread-specific execution paths and should not be applied to background tasks. Overusing @Mainactor can cause performance bottlenecks by unnecessarily serializing non-UI operations on the main thread.