Michael Gillett - Feature Management with LaunchDarkly: Discover safe ways to make live changes in your systems and master testing in production

Discover safe ways to make live changes in your systems and master testing in production

Michael Gillett

BIRMINGHAMMUMBAI

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To my family, for their constant advice and support, without which I would not be where I am today. I hope this book sheds some light on what I do in my job.

Michael Gillett

Writing a foreword to a book about using the software of the company you cofounded veers dangerously close to "going to a concert and wearing the band's t-shirt" levels of cheerleading. The opportunity here is worth it though as the CTO and cofounder of LaunchDarkly, I've seen firsthand the transformative impact feature management can have on an organization shifting to a digital-first world. Engineering leaders have told me that feature management has revolutionized the way they deliver software. I've seen data quantitatively demonstrating the positive change feature management has on the speed and quality of software delivery in hundreds of organizations.

I've also seen the exact opposite reaction to the idea of feature management. Transformative impact? Revolutionary change? We're talking about feature flags. They're just if statements in code, right? Why would such a simple concept need a third-party tool or a full-fledged book? One of my favorite Hacker News comments about LaunchDarkly sums up the sentiment well "Isn't this just a hash table?" Or, even better: "Is there really a venture-backed company out there doing booleans as a service?"

What I've come to learn from founding LaunchDarkly is that both sides are right and that's what makes feature management worth learning about. Feature flags are incredibly simple, and yet, they can transform the way you develop software.

There's no better way to learn this than from someone that's lived it firsthand.

Michael was one of the earliest customers of LaunchDarkly, having started using the platform in 2016. As such, he brings a unique perspective to his book that of a long-time user who's been along for the entire journey, from the decision to bring in a feature management solution, to initial adoption, to widespread rollout and steady-state use. This perspective is what makes his book so powerful Michael's writing combines his many years of experience with the LaunchDarkly platform with his deep understanding and insight into the value of feature management.

Michael's book is a helpful guide for anyone considering or currently adopting feature management. If you're at the beginning of your journey, you'll find answers to your questions about the business value of feature management. You'll get a tour of the most common use cases for feature management from mitigating risk with kill switches to building a practice of experimentation. You'll discover what capabilities you need in a feature management platform upfront not just today's needs, but the needs that you'll eventually grow into as your practice evolves. Finally, you'll learn how to best set up and structure the LaunchDarkly platform for your organization from the outset following best practices learned over years of experience.

Michael's book is one of the most complete resources on LaunchDarkly that I've seen. I'm confident that after reading his work, you'll come to the same conclusion that I have that feature management is both incredibly simple and incredibly powerful, and will soon be a standard practice for any modern software development team.

John Kodumal

CTO and cofounder of LaunchDarkly

Michael Gillett is a head of development and a full-stack software engineer residing in London, UK. He has worked with feature management and LaunchDarkly for several years and has defined processes and techniques to enable teams to get the most from this approach to software delivery. He often talks on this subject at conferences and events.

Michael graduated from the University of Hertfordshire with an MSc in computer science and a BEng in electrical and electronic engineering in 2012. Since 2012 Michael has been a Microsoft MVP, currently in the Windows Insider category.

I want to thank all those who have supported and encouraged me throughout the process of authoring this book, especially my parents and brother. I want to thank all those at Packt for this opportunity and for your help and feedback during the development of this book, including the technical reviewers, Dawn and Daniel.

Dawn Parzych is a developer marketing manager at LaunchDarkly where she helps developers ship code fast and safely. She specializes in the socio-technical aspects of technology and how humans are often the hardest part. Her career in tech has included roles with companies such as Catchpoint and F5. Her mission is to make tech more accessible and inclusive by using straightforward language and fewer buzzwords. Dawn recently relocated from the Pacific Northwest to the Midwest and she's slowly adjusting to life without mountains and oceans.

Daniel Yefet has more than 10 years of experience in web development and is currently working as a lead developer in a London-based technology company. He focuses on web performance and experimentation using technology within the JavaScript ecosystem, such as Node.js and React. In his spare time, he loves spending time with his wife and kids, playing music, and coding!