swift-architecture-audit

Swift Architecture Audit

Instructions

Step 1: Explore the Project Structure

Identify the UI framework in use (SwiftUI, UIKit, or Mixed) by scanning the project — look for @main, UIApplicationDelegate, or UIHostingController. Then load the matching structure reference from ../swift-project-setup/references/ and use it as the baseline when identifying structural deviations.

Use subagents to parallelize exploration of large codebases.

Scan for:

• All feature folders and their naming patterns
• Number of UIViewController subclasses vs ViewModel types
• Number of SwiftUI View types
• Presence of protocol files in Core/ or Protocols/
• Existing test targets and approximate test count

Step 2: MVVM Compliance Check

Read representative files from 3-5 key features. Look for:

Red flags (report each with file:line):

• Business logic, network calls, or storage access directly inside SwiftUI View bodies
• Business logic inside UIViewController subclasses
• URLSession.shared or UserDefaults.standard called from Views or ViewControllers
• Missing ViewModel for any screen with non-trivial state
• @State or @StateObject holding data that belongs in a ViewModel or service

Green flags (note these):

• ObservableObject or @Observable ViewModels with clear state
• Services and repositories injected via initializer or @Environment
• Thin View layer (only layout and presentation)
• Coordinator / navigation layer separate from ViewModels

Step 3: Testability Assessment

For each audited type, check:

• Are dependencies hardcoded (let service = NetworkService()) instead of injected?
• Do networking/storage types hide behind protocols?
• Are global singletons used without injection support?
• Is there any existing test coverage? How much?
• Are ViewModels testable in isolation (no UIKit/SwiftUI imports)?

Scoring:

• High testability: Protocols + DI everywhere, existing tests
• Medium testability: Some DI, some singletons, few tests
• Low testability: No protocols, no DI, no tests — refactoring needed before testing is possible