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Learn TDD in C# with xUnit and Moq. Write tests first, code second with practical examples, best practices, and common pitfalls. Start writing better C# today. Test-Driven Development (TDD) in C# flips the way most developers write code: instead of writing a feature and hoping your tests catch the bugs later, you write a failing test first , then write just enough code to make it pass. In this hands-on tutorial you'll learn TDD in C# using xUnit for testing and Moq for mocking dependencies. By the end you'll understand not just how to write tests first and code second, but why this workflow produces cleaner, more maintainable .NET applications. Whether you're a beginner searching for "how to write unit tests in C#", an intermediate developer chasing testing best practices, or a senior engineer refining your mocking strategy, this guide covers the full red-green-refactor cycle with runnable code examples. What Is TDD in C# and Why It Matters Test-Dr...

Learn event-driven architecture in C# with practical examples. Master events, delegates, and messaging to build loosely coupled, scalable systems. Start now! If you have ever watched a codebase turn into a tangled mess where changing one class breaks five others, you already understand the problem that event-driven architecture in C# was designed to solve. Event-driven architecture (EDA) lets components communicate through events instead of direct method calls, so your services stay loosely coupled, independently testable, and far easier to scale. In this tutorial you will learn how event-driven architecture works in C#, when to use it, and how to implement it with practical, runnable code — from basic delegates and events all the way to a full-blown event bus and message queues. Whether you are a beginner searching "how to use events in C#", an intermediate developer looking for publish/subscribe best practices, or a senior engineer designing distributed systems, th...

Learn API versioning in ASP.NET Core with real code examples — URL, header, and query string strategies. Build APIs that never break clients. Start now! API versioning in ASP.NET Core is one of those topics every backend developer eventually runs into — usually the hard way. You ship an API, mobile apps and third-party clients start depending on it, and then the business asks for a change that would break every one of them. Versioning is how you evolve your API without burning down the integrations built on top of it. In this guide, you'll learn the four main API versioning strategies, how to implement each one in ASP.NET Core using the official Asp.Versioning packages, how to version Minimal APIs, and the best practices (and pitfalls) that separate a maintainable API from a support nightmare. Why API Versioning Matters An API is a contract. Once a client — a React frontend, an iOS app, a partner's integration — starts consuming it, you no longer fully own its sha...

Learn the Repository and Unit of Work pattern in C# with runnable EF Core examples, best practices, and pitfalls. Master clean data access today. If you've ever felt your data access code turn into a tangled mess of DbContext calls scattered across controllers, you're not alone. The repository pattern in C# is one of the most searched-for solutions to this exact problem — and when you pair it with the Unit of Work pattern, you get a clean, testable, and maintainable data access layer that scales with your application. In this tutorial, you'll learn exactly how to implement both patterns correctly using Entity Framework Core, why they matter, and the common pitfalls that trip up even experienced developers. Whether you're a beginner searching for "how to use the repository pattern," an intermediate developer looking for best practices, or a senior engineer weighing the trade-offs, this guide has you covered with practical, runnable examples. What Is...

Learn TDD in C# using xUnit and Moq. Write tests first, code second with step-by-step examples and best practices. Start building better software today. TDD in C#: Why Writing Tests First Changes Everything TDD in C# is a development practice where you write a failing test before writing the production code that makes it pass. It sounds backwards, but test driven development in C# produces cleaner designs, fewer bugs, and code you can refactor with confidence. In this guide, you will learn how to practice TDD using xUnit and Moq — the two most popular testing libraries in the .NET ecosystem. If you have ever spent hours debugging a regression that slipped through manual testing, TDD is the answer. Instead of treating tests as an afterthought, you make them the driving force behind your design decisions. By the end of this article, you will have a complete, working C# TDD example you can apply to your own projects. What Is Test Driven Development in C#? Test driven deve...

Learn the most important C# design patterns with real code examples. Master Factory, Singleton, Observer, and Strategy patterns step by step. C# Design Patterns Every Developer Must Know in 2026 C# design patterns are proven solutions to recurring software design problems. Whether you are building a small console application or a large enterprise system, understanding design patterns will make your code more maintainable, flexible, and scalable. In this tutorial, you will learn the four most essential design patterns in C# — Factory, Singleton, Observer, and Strategy — with practical code examples you can use in your projects right away. Design patterns are not just academic concepts. They are battle-tested blueprints that thousands of professional developers use every day across companies like Microsoft, Google, and Amazon. The Gang of Four (GoF) originally catalogued 23 patterns in 1994, and they remain just as relevant in modern C# and .NET development. Why Should Yo...

Learn CQRS with MediatR in ASP.NET Core. Step-by-step tutorial with code examples, best practices, and real-world patterns. Start building today! CQRS with MediatR in ASP.NET Core — The Complete Guide If you've been building ASP.NET Core applications for a while, you've probably noticed how controllers bloat with business logic over time. MediatR in ASP.NET Core solves this by implementing the mediator pattern, which pairs perfectly with the CQRS pattern in C# to create clean, testable, and maintainable applications. In this tutorial, you'll learn how to implement command query separation from scratch with practical, runnable code examples. CQRS — Command Query Responsibility Segregation — is an architectural pattern that separates read operations (queries) from write operations (commands). Instead of using the same model and service layer for both reads and writes, you create dedicated paths for each. MediatR acts as the glue, routing commands and queries to ...