Uncover surprises, risks, and potentially serious bugs with exploratory testing. Rather than designing all tests in advance, explorers design and execute small, rapid experiments, using what they learned from the last little experiment to inform the next. Learn essential skills of a master explorer, including how to analyze software to discover key points of vulnerability, how to design experiments on the fly, how to hone your observation skills, and how to focus your efforts.

Software is full of surprises. No matter how careful or skilled you are, when you create software it can behave differently than you intended. Exploratory testing mitigates those risks.

Part 1 introduces the core, essential skills of a master explorer. You'll learn to craft charters to guide your exploration, to observe what's really happening (hint: it's harder than it sounds), to identify interesting variations, and to determine what expected behavior should be when exercising software in unexpected ways.

Part 2 builds on that foundation. You'll learn how to explore by varying interactions, sequences, data, timing, and configurations. Along the way you'll see how to incorporate analysis techniques like state modeling, data modeling, and defining context diagrams into your explorer's arsenal.

Part 3 brings the techniques back into the context of a software project. You'll apply the skills and techniques in a variety of contexts and integrate exploration into the development cycle from the very beginning.

You can apply the techniques in this book to any kind of software. Whether you work on embedded systems, Web applications, desktop applications, APIs, or something else, you'll find this book contains a wealth of concrete and practical advice about exploring your software to discover its capabilities, limitations, and risks.

Table of Contents

Part I - Establishing Foundations

1. On Testing and Exploration

2. Charter Your Explorations

3. Observe the Details

4. Find Interesting Variations

5. Evaluate Results

Part II - Adding Dimensions

6. Vary Sequences and Interactions

7. Explore Entities and Their Relationships

8. Discover States and Transitions

9. Explore the Ecosystem

Part III - Putting It in Context

10. Explore When There Is No User Interface

11. Explore an Existing System

12. Explore Requirements

13. Integrate Exploration Throughout

A1. Interviewing for Exploratory Testing Skills

A2. Test Heuristics Cheat Sheet

About the Author

Elisabeth Hendrickson is a tester, developer, and Agile enabler. A seasoned veteran, she wrote her first line of code in 1980, and almost immediately found her first bug. In 2010 she won the prestigious Gordon Pask Award from the Agile Alliance. She is best known for her Google Tech Talk on Agile Testing as well as her wildly popular Test Heuristics Cheatsheet. She splits her time between teaching, speaking, writing, programming, and working on Agile teams that value her obsession with testing.