How this book is organized: A roadmap I organized this book into three sections with 13 chapters. Part 1 introduces Ia C and how you, as an individual, write it. •Chapter 1 defines Ia C and its benefits and principles. The chapter explains that the book has examples in Python, run by Hashi Corp Terraform, and deployed to Google Cloud Platform (GCP). I also discuss the tools and use cases you’ll encounter in your Ia C journey. •Chapter 2 dives into the principle of immutability and how you can migrate existing infrastructure resources to Ia C. It also covers the practices of writing clean Ia C. •Chapter 3 offers a few patterns for dividing and grouping infrastructure resources into modules. Each pattern includes an example and a list of use cases. •Chapter 4 covers how to manage dependencies among infrastructure resources and modules and decouple them with dependency injection and some common patterns. Part 2 describes how to write and collaborate on Ia C as a team. •Chapter 5 organizes the practices and considerations for expressing Ia C in different repository structures and sharing it across your team. •Chapter 6 provides an infrastructure testing strategy. It describes each type of test and how to write them for Ia C. •Chapter 7 applies continuous delivery to Ia C. It covers a high-level view of branching models and how your team can use them to change infrastructure. •Chapter 8 provides techniques to build secure and compliant Ia C, including testing and tagging. Part 3 covers how to manage Ia C across your company. •Chapter 9 applies immutability to infrastructure changes, including an example for blue-green deployments. •Chapter 10 refactors a large body of Ia C to improve its maintainability and mitigate the blast radius of failed changes to one codebase. •Chapter 11 describes reverting Ia C and rolling forward changes to the system. •Chapter 12 addresses the use of Ia C to manage cloud computing costs. It includes an example for cost estimation of Ia C. •Chapter 13 completes the book with practices to manage and update Ia C tools. You will find that many concepts build on each other throughout the book, and it may help to read the chapters in order if you have not previously practiced Ia C. Otherwise, you can choose the sections that best apply to the challenges you face in your Ia C practice.