Symfony 3.0 focuses on backward compatibility and quality processes. It maintains the continuous upgrade path for applications to seamlessly migrate to newer versions of Symfony. Symfony 3.0 itself does not contain major new features, but rather builds upon the improvements already included in Symfony 2.8 through strict quality standards and processes. These include triggering deprecation notices, continuous integration testing, and guidelines to help third party libraries also maintain backward compatibility when upgrading their dependencies.