swift-concurrency-macos

What problem does it solve?

Writing async Swift code for macOS that interacts with AppKit, XPC services, and background daemons often leads to data races, main thread crashes, and concurrency bugs when mixing legacy AppKit patterns with modern Swift concurrency. This Skill eliminates those risks by providing production-grade, macOS-specific concurrency patterns validated against Apple's latest documentation and WWDC sessions.

Core Features & Use Cases

• Actor & Task Management: Implement thread-safe state with actors, structured task groups, and cooperative cancellation for parallel I/O and background work.
• AppKit Bridging: Safely update UI from async contexts, handle legacy AppKit delegate callbacks, and avoid common main thread and run loop pitfalls.
• XPC & Daemon Concurrency: Build async-safe XPC services and background launchd daemons without crashes or data races.
• Use Case: A macOS document editor can use this Skill to safely process large files in parallel while updating the UI, and communicate with a privileged helper daemon via XPC without concurrency errors.

Quick Start

Use the swift-concurrency-macos skill to refactor your existing NSDocument subclass to use @MainActor isolation and add a parallel task group for batch thumbnail generation without data races.