Concurrency in C# (.NET): Asynchrony, Parallelism, and Multithreading

Modern .NET applications must be fast and responsive, and this is impossible without understanding concurrency. The book "Concurrency in C# (.NET)" is a practical guide that will take you step by step from the basics of asynchronous programming to complex scenarios of parallel data processing and building distributed systems.

You will learn how to properly use async and await, manage tasks (Task), avoid locks, and synchronize access to shared resources. Special attention is given to the TPL (Task Parallel Library), parallel loops (Parallel.For, Parallel.ForEach), as well as working with ConcurrentCollection and PLINQ.

Who this book is for:

• C# developers who want to move from simple single-threaded applications to high-load systems.
• Backend engineers working with ASP.NET Core, SignalR, and microservices.
• Professionals facing performance issues (data races, deadlocks, starvation).
• Anyone who wants to understand the difference between asynchrony, multithreading, and parallelism on the .NET platform.

What you will learn:

• How the task scheduler (TaskScheduler) and the .NET thread pool work.
• How to properly design async methods and avoid hidden errors (e.g., capturing the synchronization context).
• How to use Channel, SemaphoreSlim, ReaderWriterLockSlim, and other synchronization primitives.
• How to implement Producer-Consumer, Pipeline, and MapReduce patterns in C#.
• How to test and debug concurrent code using System.Threading.Channels and Microsoft.Diagnostics.Tracing.
• How to use IAsyncEnumerable for streaming data processing.

The book contains numerous code examples ready for use in real projects. You will learn to write not only fast but also safe programs resistant to race conditions and deadlocks. After reading, you will be able to confidently design systems that efficiently utilize multi-core processors and asynchronous I/O operations.

Concurrency in C# (.NET) is not just theory, but a set of tools and techniques that will immediately improve the quality of your code and application performance. Ideal for those who want to advance to the next level of .NET development.