Centurion: A PHP Content Management Framework (Zend-Powered)
Centurion is an open source application which is both a fully-functional CMS and a base/framework for building project-specific content management/admin systems.
It is built on top of Zend and comes with features like user/comment/navigation management, social sign-in, internal search and more besides the handling of content.
A single installation can control multiple sites and the sites can have multiple languages.
Centurion comes with an intuitive datagrid that works with any types of custom data and has capabilities like smart filtering, easy search, sorting, paging, ordering and bulk handling.
For creating + editing data, a powerful form module exists which you can create a form with your own data model. It has built-in components like rich text editor, multi select, switcher, multi upload, datepicker, error messages.
There are also many other re-usable components that will ease creating such a CMS system including caching, file handling, feed generation, lazy loading and much more.