API Development in C# (.NET): From Basics to Production

This book is a practical guide to modern API development on the .NET platform. It is designed for C# developers who want to master creating high-performance and secure web services from start to finish. You will journey from designing a simple REST API to deploying it in a production environment.

Who is this book for?

• Junior and Middle .NET developers looking to systematize their knowledge of API creation
• Backend developers from other languages transitioning to C#
• Team Leads who want to implement best practices in their projects
• Anyone who wants to learn to write clean, testable, and maintainable API code

What you will learn:

• ASP.NET Core Web API architecture: routing, middleware, filters
• RESTful API design: versioning, pagination, HATEOAS
• Working with data: Entity Framework Core, Dapper, migrations
• Authentication and authorization: JWT, Identity, OAuth 2.0
• API documentation with Swagger/OpenAPI
• Testing: unit and integration tests for APIs
• Performance optimization: caching, background tasks, SignalR
• Deployment: Docker, Kubernetes, CI/CD pipelines

The book follows a "from simple to complex" principle. Each chapter contains practical code examples that can be immediately applied in your work. You will learn to handle errors, validate input data, log requests, and build fault-tolerant systems.

Special attention is given to modern approaches: Minimal API, gRPC, GraphQL, as well as integration with Azure cloud services. You will learn how to design APIs capable of withstanding high loads and scaling horizontally.

At the end of the book, you will find a full case study of building a microservice architecture using RabbitMQ, Redis, and PostgreSQL. This will help you understand how to apply the acquired knowledge in real-world projects.

The example code is available on GitHub and is kept up to date for .NET 8. The book is suitable both for self-study and for use as a reference in daily work.