Over time Rails applications grow, the speed of adding new features decreases. The build time increases. Many things are tested trough the browser or they’re not tested at all. The techniques described in this book will help you reduce the test time, increase the time to add new features and will make you proud of the codebase. Introducing service objects is an often recommended technique to improve the situation. Most of the blog posts in the Internet focus on simple situations, which are far from real-life Rails code. This book aims to fill the gap and teach you step-by-step how to introduce services in the typical situations.