Swift Optimise

What it does

This skill provides a comprehensive guide to optimizing Swift and SwiftUI applications for performance. It offers 19 rules categorized by priority (critical, high, and medium) covering modern concurrency, render/scroll performance, and animation performance. The guidance is tailored for iOS 26 and Swift 6.2, emphasizing features like @Observable and strict concurrency. This skill assumes a clinic modular MVVM-C architecture.

When to use it

• When migrating to Swift 6's strict concurrency (Sendable, actor isolation).
• When replacing Combine publishers with async/await.
• When implementing @MainActor isolation and actor-based concurrency.
• Before optimizing scroll or render performance.
• When building performant spring animations and transitions.

Key capabilities

• Guidance on adopting Swift 6 strict concurrency practices (Sendable).
• Recommendations for migrating from Combine to async/await.
• Strategies for decomposing views to reduce state invalidation.
• Best practices for optimizing scroll and render performance using lazy containers, Canvas, and TimelineView.
• Techniques for creating high-performance animations and transitions.
• Suggestions on utilizing SwiftUI Instruments for profiling.

Example prompts

• "How can I replace a Combine publisher with async/await?"
• "What's the best way to decompose views in Swift 6?"
• "Show me how to use Canvas and TimelineView for high-performance rendering."

Tips & gotchas

• This skill assumes familiarity with the clinic modular MVVM-C architecture.
• The guidance is specifically targeted for iOS 26 and Swift 6.2; some recommendations may not be applicable to older versions.
• Always profile your application using SwiftUI Instruments before implementing any optimization techniques.