Swift Development Skill

A Claude Code skill for comprehensive Swift iOS/macOS development. Provides patterns, commands, and tooling for building, testing, and deploying Swift applications.

Installation

Copy the skill to your Claude skills directory:

cp -r swift-development ~/.claude/skills/

Or manually create and copy:

mkdir -p ~/.claude/skills/swift-development
cp -r swift-development/* ~/.claude/skills/swift-development/

Usage

Invoke the skill in Claude Code:

/swift-development

Or reference it naturally - Claude will activate the skill when working on Swift projects.

What's Included

Quick Patterns (SKILL.md)

• SwiftUI with Observable (iOS 17+) and ObservableObject (iOS 13+)
• Navigation patterns: NavigationStack (iOS 16+), NavigationView (iOS 13-15), coordinator pattern
• Swift 6 concurrency: async/await, actors, Sendable
• XCTest and Swift Testing frameworks (with expanded examples)
• Common xcodebuild and simctl commands

Reference Documentation

Topic	File
Swift Package Manager	references/spm.md
xcodebuild commands	references/xcodebuild.md
Simulator control	references/simctl.md
Code signing	references/code-signing.md
Swift 6 concurrency	references/concurrency.md
Architecture patterns	references/architecture.md
CI/CD setup	references/cicd.md
Troubleshooting	references/troubleshooting.md

Helper Scripts

Script	Purpose
scripts/new_package.sh	Create new Swift package with config files, version warnings, and naming guidance
scripts/run_tests.sh	Run tests with parallel execution and coverage (SPM or xcodebuild)
scripts/format_and_lint.sh	Format and lint Swift code (SwiftFormat, SwiftLint, swift-format)
scripts/simulator.sh	Quick simulator management (boot, install, launch, screenshots, etc.)

Features:

• Colored output: All scripts use color-coded messages (green for steps, yellow for warnings, red for errors)
• Smart validation: new_package.sh provides comprehensive warnings for:
  • Swift/Xcode version compatibility (e.g., Swift 6.0 requires Xcode 16+)
  • Package naming conventions (PascalCase guidance)
  • Git repository nesting (suggests using submodules)
  • Missing tools (SwiftFormat/SwiftLint installation checks)
• Robust error handling: Prerequisite checks with helpful installation instructions
• Styled success indicators: Clear visual feedback when operations complete

Asset Templates

• assets/Package.swift.template - Swift package template
• assets/.swiftformat - SwiftFormat configuration
• assets/.swiftlint.yml - SwiftLint configuration
• assets/ExportOptions/ - Archive export plist templates (App Store, Ad Hoc, Development)

Official Documentation

For authoritative reference, this skill points to Apple's official Swift documentation:

• Swift Documentation: https://developer.apple.com/documentation/swift
• SwiftUI: https://developer.apple.com/documentation/swiftui
• Swift Concurrency: https://developer.apple.com/documentation/swift/concurrency
• Swift Testing: https://developer.apple.com/documentation/testing

Live Documentation Fetching: The skill instructs Claude to use WebFetch to retrieve current documentation. Since Apple's documentation sites are JavaScript SPAs that cannot be fetched programmatically, the skill uses GitHub-based sources instead:

• Swift Testing: https://github.com/apple/swift-testing
• Swift Evolution: https://github.com/apple/swift-evolution/tree/main/proposals
• Swift Compiler Docs: https://github.com/apple/swift/tree/main/docs
• Swift Async Algorithms: https://github.com/apple/swift-async-algorithms

These sources provide accurate, up-to-date information on Swift language features, testing frameworks, and package APIs.

Requirements

• macOS with Xcode 15+ (Xcode 16+ for Swift 6 features)
• Xcode Command Line Tools: xcode-select --install

Quick Reference

# Build
swift build                    # Debug build
swift build -c release         # Release build

# Test
swift test                     # Run all tests
swift test --filter MyTest     # Run specific test

# Xcode project
xcodebuild -workspace App.xcworkspace -scheme App \
    -destination 'platform=iOS Simulator,name=iPhone 15' build

# Simulators
xcrun simctl list devices      # List devices
xcrun simctl boot "iPhone 15"  # Boot simulator
xcrun simctl install booted ./App.app  # Install app

Acknowledgments

This skill was inspired by and builds upon ios-swift-development by @aj-geddes. The original skill provided a foundation that was expanded with additional reference documentation, helper scripts, and asset templates.