Swift API Development: Creating REST and GraphQL Services for iOS/macOS

This book is a comprehensive guide to developing server-side and client-side APIs in the Swift language for the Apple ecosystem. If you are an iOS/macOS developer who wants to go beyond the mobile interface and learn how to create reliable, scalable server-side solutions, or if you already work with server-side Swift (Vapor, Kitura) and want to deepen your knowledge of API design — this book is for you.

The book systematically covers all stages of creating a modern API: from architecture design to deployment and monitoring. You will learn how to properly structure endpoints, work with authentication (JWT, OAuth2), handle errors, and optimize performance.

What you will learn:

• REST and GraphQL Basics — design principles, versioning, pagination, HATEOAS.
• Server-Side Swift with Vapor 4 — project setup, routing, middleware, working with databases (Fluent ORM).
• Client-Side API — creating a networking layer with URLSession, async/await, Combine, handling responses and errors.
• Asynchronous Programming — deep dive into async/await, actors, structured concurrency when working with the network.
• Security — encryption, attack protection, secure token storage in Keychain.
• Testing — unit tests, integration tests, mock objects, testing network requests.
• Documentation — OpenAPI/Swagger, documentation generation, tools for team collaboration.
• Advanced Topics — WebSocket, Server-Sent Events, gRPC, working with push notifications via your own API.

Who this book is for:

• iOS/macOS developers looking to master backend development in Swift.
• Full-stack developers working in the Apple ecosystem.
• Tech leads and architects designing client-server applications.
• Students and junior developers striving for professional growth.

All code examples are based on real projects and come with detailed comments. You won't just read the theory — you'll be able to immediately apply the knowledge in practice: from a simple REST service to a full-fledged microservice with GraphQL and WebSocket.

The book is written by a practicing iOS developer with 8 years of experience, who has created APIs for applications with a million-strong audience. The material is structured so that you can study it sequentially or use it as a reference when working on a specific task.

Start creating professional APIs in Swift today — and your applications will reach a new level of performance and reliability.