Neo Swift

Modern Swift (5.0+) Expert Skill

Trigger On

• The user asks to write, debug, refactor, or review Swift code.
• The project directory contains *.swift, Package.swift, or *.xcodeproj.
• Development involves iOS (SwiftUI/UIKit), macOS, or Server-side Swift (Vapor).
• Code modernization is needed (e.g., migrating to Structured Concurrency or Swift 6 language mode).

Workflow

1. Perceive (Version Awareness):

• Identify the Swift version (e.g., check Package.swift or build settings).
• Determine the platform (SwiftUI vs UIKit, Server vs App).
• Assess dependency management (Swift Package Manager, CocoaPods).

1. Reason (Planning Phase):

• Evaluate the use of modern syntax (e.g., async/await, Result, @propertyWrapper).
• Decide on memory management strategies (ARC, weak/unowned).
• For UI tasks, prioritize SwiftUI for modern apps or UIKit for legacy support.

1. Act (Execution Phase):

• Write swifty, concise code following Apple's API Design Guidelines.
• Implement type-safe and protocol-oriented solutions.
• Leverage Structured Concurrency (Task, async let) for asynchronous operations.

1. Validate (Standard Validation):

• Check for memory leaks (retain cycles) using capture lists.
• Verify Swift 6 concurrency safety (data race detection).
• Ensure naming conventions follow the standard lowercamelCase for members and PascalCase for types.

Feature Roadmap (Swift 5.0 - 6+)

Swift 5.0 - 5.4 (Foundation)

• Result Type: Standardized error handling.
• Property Wrappers: Encapsulating property logic (e.g., @Published).
• Opaque Types: Hiding implementation details (some View).
• Result Builders: DSL support for SwiftUI.

Swift 5.5 - 5.10 (Modern Concurrency)

• Async/Await: Linear asynchronous code.
• Actors: Thread-safe state isolation.
• Distributed Actors: Communicating across processes.
• Non-copyable Types: Explicit control over object ownership.

Swift 6+ (Safety & Performance)

• Full Data Isolation: Compile-time data race prevention.
• Typed Throws: Explicitly defining error types.
• Embedded Swift: Running Swift on restricted environments.

Coding Standards

• Conciseness: Use trailing closures and shorthand argument names where appropriate.
• Safety: Prefer if let or guard let over force unwrapping (!).
• Purity: Prefer struct (Value Types) over class (Reference Types) for data models.
• Concurrency: Avoid Thread.sleep or legacy completion handlers; use structured concurrency.

Deliver

• Version-Optimized Code: Provide code using the best features of the target Swift version.
• SwiftUI/UIKit Insights: Recommend patterns based on the UI framework used.
• Concurrency Migration: Provide strategies for moving to Swift 6 strict concurrency checks.

Validate

• Ensure code compiles without warnings in the target Swift version.
• Validate that closure capture lists correctly handle object lifecycles.
• Confirm that error handling uses the do-catch or throws patterns correctly.

Documentation

Official References

• Swift API Design Guidelines
• The Swift Programming Language Guide

Internal References

• [Swift Coding Style and Naming Conventions](reference/coding-style.md)
• [Swift Anti-Patterns and Best Practices](reference/anti-patterns.md)
• [Modern Swift Patterns Guide](reference/patterns.md)

Source & license

This open-source skill is cataloged on AgentStack and links to its original source — we do not rehost the code.

• Author: Benknightdark
• Source: Benknightdark/neo-skills
• License: MIT
• Homepage: https://neo-blog-iota.vercel.app/

Install and usage instructions live in the source repository linked above.