MATTHIAS NOBACK
Writing healthy, reusable Symfony2 code
Rector - The Power of Automated Refactoring
Rector is an extremely powerful tool that can instantly improve the code quality of your PHP projects.
You'll learn about asynchronous integration, independent deployability, continuous delivery, and immediate versus eventual consistency.
Decoupling your code is a way to make it future-proof (without doing too much work that "you ain't gonna need").