API Development in JavaScript (Node.js)

The book "API Development in JavaScript (Node.js)" is a comprehensive practical guide for anyone who wants to master building server-side applications and APIs with Node.js. Author Andrey Volkov, an experienced backend developer with 8 years of experience, shares proven approaches and real-world cases from commercial development.

What is this book about?

The book covers the full API development cycle — from architecture design to deploying a finished product. You will learn how to build both classic RESTful services and modern GraphQL APIs. Special attention is paid to performance, security, and scalability.

Main topics:

• API design: REST, GraphQL, WebSocket — when to choose which
• Popular frameworks: Express.js, Fastify, Koa — comparison and best practices
• Working with databases: MongoDB (Mongoose), PostgreSQL (Sequelize, Prisma)
• Authentication and authorization: JWT, OAuth 2.0, session-based approaches
• Data validation and error handling
• Testing: unit tests (Jest), integration tests (Supertest)
• API documentation: Swagger/OpenAPI, GraphQL Playground
• Deployment: Docker, CI/CD, Nginx, cloud platforms (Heroku, AWS)
• Monitoring and logging: Winston, Morgan, Sentry

Who is this book for?

• Junior developers who want to systematize their knowledge and move on to real projects
• Middle developers looking to deepen their understanding of API architecture and advanced techniques
• Frontend developers learning backend for fullstack specialization
• Team Leads who need to quickly understand modern approaches to APIs

What will you learn after reading?

• How to design an API that is easy to maintain and extend
• How to avoid common mistakes when working with asynchrony and streams
• How to set up authorization and protect your API from attacks (XSS, CSRF, SQL injection)
• How to optimize performance: caching, connection pooling, clustering
• How to automate testing and deployment
• How to document an API so it is convenient for your team and clients to use

The book contains over 50 practical code examples, ready to use in real projects. Each chapter ends with exercises to reinforce the material. At the end of the book, you will find a checklist for launching an API into production and a list of recommended tools.

This is not just a textbook — it is a desk reference for anyone professionally developing with Node.js. Regardless of your current level, after reading you will be able to create reliable, secure, and performant APIs that can handle any load.