MidnightCMS is a Symfony Framework based Content Management System. His first purpose is to combine the power of Symfony with the ability to create custom pages (like "About us" for example). You can have your main application working on the same instance of symfony with customizable pages included without any other development needed.
The CMS contains a backend that look like this:
You can use midnightCMS for multiple purposes, the first idea of this CMS is to combine a big symfony application with simple page edition. As seen in the documentation, you can for example develop normal symfony application in AppBundle and use the CMS for simple HTML content like "About us", products presentations, history page...
MidnightCMS includes a frontend editor for realtime 'wysiwyg' with the current site template. The CMS also includes a template editor, where you can edit the complete site rendering, with some custom functions like make a link to another page, or generate a list of the subpages, a breadcrumb with link to parent pages...
The CMS himself is by the way extensible. You can for example create your own page type, as explained in the documentation.
There is also an example section on this website where you can learn how to create page types, or even some tips for using the CMS at your advantage.
If you want to report bugs, request features or even contribute to this project, You can go to the project's GitHub page and if you have questions or just need help setting up the CMS you can contact me on Twitter @VincentFoulon80