Refactoring Swift Code: iOS and macOS Applications

The book "Refactoring Swift (iOS/macOS) Code" is a practical guide for developers who want to transform "working" code into an elegant, maintainable, and scalable architecture. Unlike abstract theoretical manuals, this book is focused exclusively on the Apple ecosystem: Swift, UIKit, SwiftUI, Core Data, Combine, and other frameworks.

What is this book about?

You will learn to identify and eliminate typical code smells in iOS/macOS projects: Massive View Controller, God Object, excessive use of optionals, spaghetti code in delegates, and singletons. The book offers step-by-step refactoring techniques with real-world examples from practice — from reworking VIPER/MVVM architecture to optimizing memory and thread management.

Who is this book for?

• iOS/macOS developers with 1+ year of experience who want to improve code quality
• Team Leads and architects implementing code review and development standards
• Developers transitioning from Objective-C to Swift
• Professionals preparing for interviews at top companies (improving architectural solutions)

What will you learn?

• How to safely refactor code without the risk of breaking existing functionality
• SOLID principles as applied to Swift and Cocoa Touch
• Refactoring patterns: Extract Method, Move Field, Replace Conditional with Polymorphism, and others
• Working with tests: how to cover refactoring with Unit tests and UI tests (XCTest, Quick/Nimble)
• Migration from UIKit to SwiftUI: a step-by-step strategy
• Performance optimization: eliminating memory leaks, optimizing Core Data queries
• Refactoring legacy code: Strangler Fig strategy, Feature Flags

Why is this book useful?

Each chapter contains ready-made checklists for code review, "before" and "after" examples with comments, as well as exercises to reinforce the material. The book teaches you not just to "rewrite code," but to do it systematically, with minimal risks and maximum benefit for the project. You will gain tools that you can immediately apply in your Xcode project — whether it's a small application or an enterprise solution.

Perfect for those who are tired of "technical debt" and want to write code that is pleasant to read and easy to maintain.