Modern Swift

This covers Swift 6.2's strict concurrency model with async/await, actors, and Sendable constraints that catch data races at compile time. You'll want this when migrating from completion handlers to modern patterns, fixing Sendable errors, or wrangling shared state without locks. The reference guide is thorough on task groups, cancellation, and the actor re-entrancy gotchas that bite everyone. The real value is in the migration patterns and the blunt guidance on when not to reach for @unchecked Sendable as a quick fix. If you're still using DispatchQueue for everything or your codebase is drowning in completion handler pyramids, this walks through the proper modern alternatives.