Comprehensive Testing in Elixir Explained

Comprehensive Testing in Elixir Explained: From ExUnit to Property-Based and Mutation Testing for Zero-Bug Releases and Confident Refactoring

What separates software that thrives from code that crumbles under pressure? Confidence. Confidence to refactor without fear, to release updates without late-night fire drills, and to scale systems without brittle regressions. In Elixir-where concurrency and fault tolerance are the norm-confidence is impossible without comprehensive testing.

This book delivers a complete framework for mastering testing in Elixir, from the foundations to advanced strategies proven in production. You'll start with ExUnit, learning how to structure and run efficient, maintainable tests. From there, you'll progress to mocking with Mox, property-based testing with StreamData, mutation testing for resilience, and contract testing to eliminate integration drift. Along the way, you'll see how to plug testing into CI/CD pipelines, measure coverage, test Phoenix applications, and safeguard distributed systems.

By working through these chapters, you'll gain the skills to:

Write clear, effective ExUnit tests that catch bugs before users do.

Apply mocking, stubbing, and contract testing to tame external dependencies.

Leverage property-based and mutation testing to uncover hidden edge cases and strengthen weak suites.

Integrate tests seamlessly into continuous integration and delivery pipelines.

Build a testing culture that scales with your team and codebase.

Packed with real-world examples and lessons from teams running mission-critical Elixir systems, this book reframes testing as leverage, not overhead. With the right approach, tests stop being a burden and become your engine of fearless development.

If you're ready to release with confidence, refactor boldly, and build Elixir systems that endure, this guide is your essential playbook.

Take the next step toward zero-bug releases-add this book to your toolkit today.