Symfony is a high performance PHP framework for developing MVC web applications. Symfony1 allowed for ease of use but its shortcoming was the difficulty of extending it. However, this difficulty has now been eradicated by the more powerful and extensible Symfony2. Information on more advanced techniques for extending Symfony can be difficult to find, so you need one resource that contains the advanced features in a way you can understand. This tutorial offers solutions to all your Symfony extension problems. You will get to grips with all the extension points that Symfony, Twig, and Doctrine offer and understand how each of them can be specifically leveraged to achieve cleaner, better structured, and re-usable code for your application. Beginning with the core concepts of Services and Listeners, you quickly move on to learn the complexity of forms, creating commands, and implementing security, and finally you will share these extensions with others. This book will tell you everything you need to know to regain control of your code, to keep things simple, and share it within your application(s) or even the world. Whether you have already written extensions for Symfony2 or not, this book will be a useful guide through all possible types of extensions, and how each of them can be implemented and leveraged in your own applications.