Software
MODX
MODX is a free, open source content management system and digital experience platform. The CMS gives you full control over your creative, editorial vision and the experience you deliver. MODX is written in the programming language PHP and supports both MySQL and Microsoft SQL Server databases. The CMS is openly developed and released under the GPL license, and allows contribution.
Joomla
Joomla is a free and open-source content management system written in PHP. The CMS is built entirely by volunteers from all over the world and has a strong community that provide educational resources, and extensions.
Kentico Kontent
Kentico Kontent is a leading provider of managed and headless content management systems. Kentico Kontent empowers enterprise business users and developers alike. The Modular content structure of Kentico Kontent frees developers to build any experience on top of their favorite tech stack. After the initial build, marketers can create new experiences and manage the components that appear across every channel.
Puck CMS
Puck is an open source, multi-platform .NET core cms. Fast, scalable, code-first, unobtrusive and extensible with powerful querying and Lucene integration
Fork CMS
Fork CMS is a free and open-source, easy to use content management system built with PHP and Symfony Components. The content management system features an intuitive administration panel that makes it easy to create and manage content for the web. Fork CMS also comes packed with apps that can be installed to extend the feature set of the content management system.
Ponzu CMS
Ponzu is a powerful, free and open-source HTTP server framework and CMS. It provides automatic, free, and secure HTTP/2 over TLS with Let's Encrypt, a useful CMS and scaffolding to generate content editors, and a fast HTTP API on which to build modern applications.
TinaCMS
Tina is an open-source site editing toolkit and headless CMS for React-based sites like Gatsby & Next.js
FeinCMS
FeinCMS is a bare bones content management system written in Python on-top of the web framework Django. The CMS is built to know nothing about your content, and includes an admin interfaces that can handle content types. It lets you reorder page content blocks using a drag-drop interface, and you can add as many content blocks to a region (sidebar, header, etc) as you want. FeinCMS was built this way to allow for maximum flexibility, where developers, designers and content managers can create a unique site, tailored for their type of content and future patterns.