swift-concurrency-expert

Fix Swift concurrency data race errors by applying minimal safe patches such as annotating types with @MainActor, adding Sendable conformance, and creating isolated conformances to ensure thread-safe access to shared mutable state.

Migrate completion handlers to async/await in Swift 6.2+ by replacing older callback patterns with modern async functions, then validating the changes through full project rebuilds and test runs to ensure no regressions.

Actor isolation helps with data-race safety in Swift libraries and frameworks by restricting mutable state access to a single actor context, ensuring concurrent operations do not conflict and maintaining codebase maintainability.

Triage and diagnose concurrency issues across a Swift project by capturing compiler diagnostics, evaluating actor contexts, and reviewing default isolation settings to identify where data races occur and what requires Sendable conformance.

Sendable conformance fails during refactoring when types contain mutable non-isolated state or capture non-Sendable references across actor boundaries, requiring you to add actor isolation or restrict mutable state access to ensure safe concurrency.

You can review Swift concurrency in UI apps by applying the smallest safe fixes to annotate UI-bound types with @MainActor, ensuring thread-safe access to mutable state and verifying changes through rebuilding and test runs.