Book Image

Feature Management with LaunchDarkly

By : Michael Gillett
Book Image

Feature Management with LaunchDarkly

By: Michael Gillett

Overview of this book

Over the past few years, DevOps has become the de facto approach for designing, building, and delivering software. Feature management is now extending the DevOps methodology to allow applications to change on demand and run experiments to validate the success of new features. If you want to make feature management happen, LaunchDarkly is the tool for you. This book explains how feature management is key to building modern software systems. Starting with the basics of LaunchDarkly and configuring simple feature flags to turn features on and off, you'll learn how simple functionality can be applied in more powerful ways with percentage-based rollouts, experimentation, and switches. You'll see how feature management can change the way teams work and how large projects, including migrations, are planned. Finally, you'll discover various uses of every part of the tool to gain mastery of LaunchDarkly. This includes tips and tricks for experimentation, identifying groups and segments of users, and investigating and debugging issues with specific users and feature flag evaluations. By the end of the book, you'll have gained a comprehensive understanding of LaunchDarkly, along with knowledge of the adoption of trunk-based development workflows and methods, multi-variant testing, and managing infrastructure changes and migrations.
Table of Contents (18 chapters)
1
Section 1: The Basics
5
Section 2:Getting the Most out of Feature Management
11
Section 3: Mastering LaunchDarkly

Learning testing in production

For some, the idea of testing in production seems contrary to how testing should be done. For a while, the best practice has been that testing should never be done in production: the impact and cost of finding out that features do not work as expected are far too expensive by the time the feature is already in a customer-facing environment. The potential negative impact to both the bottom line and the time taken to build and deliver a feature makes it a very wasteful approach.

However, when feature management is used, the practice of testing in production removes all that risk. In fact, dynamically enabling features for customers in a production environment does not just make this approach safer, but in several ways, it is actually superior to testing features and functionality on any other environment.

Testing in this manner relies heavily on the use of temporary feature flags, as by their very nature, they are designed to help get new functionality...