Jakub Jarosz

Security, System & Electrical Automation

50 Go Testing Mistakes

2025-09-16 Go Books Jakub Jarosz

About the book

50 Go Testing Mistakes is a collection of patterns gone wrong. The subtle omissions, false assumptions, and non-idiomatic structures that we can find in many Go projects have grown over the years. Each chapter focuses on a specific mistake, drawing from real open source projects deployed in production systems. Then, each chapter offers a clear, testable path to idiomatic improvement. You’ll see examples of what went wrong, why it happened, and how to build a more reliable system next time.

Throughout the book, I use analogies and examples from mechanics and electrical engineering — fields where I worked for many years, fields where precision, repeatability, and fault tolerance are essential and non-negotiable.

The same holds for well-tested Go code. If you’re working with systems that require reliability, whether it’s an electronics assembly or a distributed Go service, minor errors can lead to big failures.

My goal isn’t to present “one true way” to test, but to help you develop a sharper eye, and the Go idiomatic way of thinking about your code, and more importantly, about your tests. Well-tested code isn’t just a safety net. It’s critical documentation for software products you build and ship. It gives you and your colleagues the confidence to refactor quickly, release frequently (even on Fridays), and sleep calmly even if you are on-call that night.

Whether you’re working on a personal project or maintaining production systems, 50 Go Testing Mistakes will guide you through the testing maze and help to write Go code you can trust.

If you’ve ever written tests that pass but don’t actually prove anything, or tests that break every time you change a line of code, you’re not alone. This book will show you how to avoid those traps, along with 49 others like them.

You’ll also learn how to:

  • Avoid flaky and brittle tests that slow down development
  • Write clear, focused, and maintainable test cases
  • Structure your test suites for scalability and readability
  • Use Go’s testing tools more effectively
  • Use Go tools for fundamental security testing
  • Catch subtle bugs early by improving test coverage and design

Let’s build tests like engineers build machines: with care, with precision, and with a deep understanding of how even the smallest parts affect the whole software product.


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