A simple template for Swift 6 and iOS development in Xcode using Agentic coding (Claude or Codex)

CLAUDE.md

Project Context

Overview

• iOS 26 SwiftUI app targeting iPhone and iPad
• Minimum deployment: iOS 26
• Swift 6 with strict concurrency
• Uses SwiftUI throughout - no UIKit unless absolutely necessary

Architecture

• MVVM with @OBservable ViewModels (NOT observableObjects)
• Views on their ViewModel as a @State property
• ViewModels handle all business logic - Views are declaritive only
• Navigation uses NavigationStack with NavigationPath - never NavigationView
• Dependency injection through the SwiftUI Enviroment
• use AppStorage for simple user prefernces
• use SwiftData for persistent models

Build System

• use BuildProject for completion (not shell commands or xcodebuild)
• Previews are available via RenderPreview
• SPM for package management - no CocoaPods
• Build target: "MyApp" iOS

Testing

• Use Swift Testing framework -- NOT XCTest
• Test functions use @Test attribute, not func textXYZ()
• Use #expect() for assertions - not XCTAssertEqual
• Test target: CLAUDEmdTests
• Run with RunAllTests or RunSomeTests MCP tools

Documentation & APIs

• Use DocumentationSearch for Apple API questions
• Do NOT hallucinate API names - Verify with the docs first
• prefer async/await - never completion handlers
• use structured concurrency (TaskGroup) over manual task management
• Error handling: use typed throws where supported

Code Style

• All new views must include a #Preview Block
• Use SF symbols for icons - reference by exact name
• Prefer Liquid Glass materials for iOS 26 UI
• File organization: one type per file
• Naming: PascalCase for types, cameCase for properties
• Group files by feature, not by type (Weather/, Profile/, Settings/)