Symfony 4 was released on November 30th 2017. Update now to the best Symfony ever!
A Better Symfony
Symfony 4 represents a rethinking of its ideas and features from the ground up to match the industry practices: application bundles are gone, config parameters are now environment variables, the application directory structure is easier to navigate and hundreds of other small improvements that will make you love Symfony.
The result is less Symfony concepts and more standard practices. Easier to learn, easier to configure, easier to install and deploy. Simple, powerful, amazing!
Symfony 4 integrates seamlessly with Symfony Flex to automate the most common tasks performed on applications. Forget about enabling bundles or creating their initial config: Symfony Flex does that for you.
The automation leverages the Symfony Recipes, which contain instructions to integrate hundreds of third-party bundles and packages into Symfony applications.
Micro by default
New applications created with Symfony 4 are based on a micro-kernel and contain 70% less code and files than new Symfony 3 apps! We worked tirelessly to optimize Symfony and remove any non-essential dependencies. The result is the leanest Symfony version ever created and the smallest footprint across all PHP frameworks.
Rock solid stability
The Symfony 4 framework is built with the latest version of the Symfony Components, the most popular set of libraries in PHP's history. Battle tested in all popular PHP projects and with more than one billion downloads.
Thanks to our unrivaled Backward Compatibility Promise, upgrading your existing applications to Symfony 4 will be a smooth experience. First, upgrade to Symfony 3.4, which provides total compatibility with any Symfony 3.x version. Then fix any reported deprecation and you are ready to upgrade instantly to Symfony 4.