On NetTuts.com there's a new screencast posted showing you a good way to create a better workflow in your PHP development using Composer and PHPUnit.
In this video tutorial, we’ll again focus on workflow. Specifically, we’ll use Composer’s built-in autoloading capabilities, along with namespacing, to make for an elegant testing experience. We’ll also review a handful of PHPUnit best practices, as we get setup with these tools.
He shows you how to use Composer to load in the packages from other projects (as well as your own) and using PHPUnit to execute unit tests for your application. He uses test-driven development, but it's not a required part of the workflow. He helps you create a simple "Calculator" test. He also shows how to manually modify the Composer classmap to load in your own classes.