iOS Concurrency Router

You MUST use this skill for ANY concurrency, async/await, threading, or Swift 6 concurrency work.

When to Use

Use this router when:

• Writing async/await code
• Seeing concurrency errors (data races, actor isolation)
• Working with @MainActor
• Dealing with Sendable conformance
• Optimizing Swift performance
• Migrating to Swift 6 concurrency

Routing Logic

Swift Concurrency Issues

Swift 6 concurrency patterns → /skill swift-concurrency

• async/await patterns
• @MainActor usage
• Actor isolation
• Sendable conformance
• Data race prevention
• Swift 6 migration

Swift performance → /skill swift-performance

• Value vs reference types
• Copy-on-write optimization
• ARC overhead
• Generic specialization
• Collection performance

Decision Tree

User asks about concurrency
  ├─ Concurrency errors?
  │  ├─ Data races? → swift-concurrency
  │  ├─ Actor isolation? → swift-concurrency
  │  ├─ @MainActor? → swift-concurrency
  │  └─ Sendable? → swift-concurrency
  │
  ├─ Writing async code? → swift-concurrency
  │
  └─ Performance optimization? → swift-performance

Critical Patterns

Swift 6 Concurrency (swift-concurrency):

• Progressive journey: single-threaded → async → concurrent → actors
• @concurrent attribute for forced background execution
• Isolated conformances
• Main actor mode for approachable concurrency
• 11 copy-paste patterns

Swift Performance (swift-performance):

• ~Copyable for non-copyable types
• Copy-on-write (COW) patterns
• Value vs reference type decisions
• ARC overhead reduction
• Generic specialization

Example Invocations

User: "I'm getting 'data race' errors in Swift 6" → Invoke: /skill swift-concurrency

User: "How do I use @MainActor correctly?" → Invoke: /skill swift-concurrency

User: "My app is slow due to unnecessary copying" → Invoke: /skill swift-performance

User: "Should I use async/await for this network call?" → Invoke: /skill swift-concurrency