Plone CMS

Plone CMS is a free and open source content management system written in Python. The CMS is built on top of the Zope application server, a free and open source web application server written in the object-oriented programming language Python. The significant strength of Plone is its flexibility, allowing users to manage the lifecycle of their workflow, from creation to publication and storage, with version control, content locking, and digital asset and document management. Plone has an active, thriving open source community that holds annual conferences, regional symposia, and many sprints all over the world. Which means that anyone if free to join and improve the codebase