Grav
A CMS project using Symfony components
Grav is a Modern, Fast, Simple and Flexible flat-file CMS. While Grav is intentionally minimal, the extensive plugin architecture allows it to be adapt to almost any task. Powerful Twig templating ensures that development is only limited by your imagination. Sophisticated caching mechanisms mean that Grav is scary fast and can scale more than other flat-file CMS systems. Utilizing Markdown for content creation and YAML for configuration ensures it is always easy to use and configure. Being flat-file based, means a Grav site is quick to install, simple to migrate, and a breeze to version.
Official website: getgrav.org