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From Zero to Hero: Writing Testable Code in C#

Learn how to easily write code with Testing in mind.

4h 30m Testing
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From Zero to Hero: Writing Testable Code in C#

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Write C# Code With Testing in Mind

If you're stuck in an endless loop of:

  • Writing code
  • Realising it's impossible to test
  • Refactoring everything from scratch

...then I've got news for you: there's a better way.

What you'll learn

  • Define explicit behaviors with clear inputs and outputs
  • Create narrow responsibilities and effective injection points
  • Master dependency isolation and break dependency chains
  • Minimize side effects and avoid test interference
  • Write testable ASP.NET Core Controllers and Entity Framework code
  • Implement testable authentication and time-dependent code

The Hidden Cost of Untestable Code

Most C# developers don't realise that every untestable line of code they write creates a time bomb.

That quick hack you used to meet a deadline? The tightly-coupled class that "just works"? The static method calls scattered throughout your codebase?

They're all silently draining your productivity, killing your confidence, and making every future change a nightmare waiting to happen.

This Course is your escape plan

I'll show you exactly how to write C# code that:

  • Actually wants to be tested - No more wrestling with your own code
  • Makes bugs obvious - Before they make it to production
  • Stays maintainable for years - Even when the original developers are long gone

In just 4 hours, you'll master the techniques that took me 15 years of painful trial-and-error to discover.

What makes this different from other Testing Courses?

This isn't about testing theory or academic patterns. This is about writing real-world C# code that you can actually test without wanting to pull your hair out.

You'll learn:

  • How to design code with explicit behaviours that practically test themselves
  • The art of creating narrow responsibilities that make unit tests easy
  • Bulletproof techniques for isolating stubborn dependencies
  • Simple ways to minimise side effects that sabotage your tests

Real solutions for real code

We'll tackle the stuff that actually matters in your day-to-day work:

  • Making ASP.NET Core controllers that don't fight your test suite
  • Designing Entity Framework code you can test without a database
  • Creating time-dependent code that doesn't need time travel to test
  • Building authentication and authorisation that's actually verifiable

By the end, you'll instinctively know how to write testable code from the start – saving you countless hours of frustration and rewrites.

Frequently Asked Questions

What is the target audience for this course?
This course is for C# developers who want to write code that's easier to test. Whether you're struggling with testing your current code or want to learn how to write more testable code from the start, this course is for you.
How is this different from a TDD course?
While TDD is about the process of writing tests first, this course focuses on the design principles that make code testable. You'll learn how to structure your code so it's easy to test, regardless of whether you practice TDD or not.
Do I need testing experience?
Basic understanding of unit testing is helpful but not required. We'll cover the fundamentals of testing as needed, focusing more on how to design testable code.
Can I apply these principles to existing code?
Absolutely! You'll learn strategies for gradually improving testability in existing codebases, identifying common anti-patterns, and refactoring them into testable designs.
What if I get stuck or have questions?
The course includes detailed explanations. Plus, you get access to our community, where you can ask questions and share experiences with other students. In any case, you can always reach out to me.

Ready to write C# code that Loves Being Tested?

Practical course for developers who want to write better, simpler, more maintainable code.

One-time payment • Lifetime access

Everything you need to succeed:

4h 30m of video content
Downloadable resources
Certificate of completion
Lifetime access to all updates
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