Concrete CMS is a Free and Open Source Content Management System for Teams

Concrete CMS is a free and open-source content management system that empowers teams of content creators, designers, and developers to build, author, and publish websites with intuitive tools and enterprise-grade security.

🚀 Overview

Concrete CMS stands out in a crowded CMS market by combining powerful functionality, ease of use, and low deployment costs. It solves the problem of teams struggling to manage complex websites securely and collaboratively, offering in-context editing, workflow approvals, version control, and compliance-ready security (ISO 27001, SOC 2, HIPAA). Used by organizations like the U.S. Army, it ensures robust performance for high-stakes sites.

This project is built for content teams, designers, developers, and enterprises needing a flexible CMS that scales from simple sites to multisite networks. It's community-driven, evolved from Concrete5, to provide a developer-friendly, extensible platform that's simple for non-technical users.

The global community built it to create an open-source alternative that's secure, customizable, and team-oriented, saving time and reducing reliance on plugins.

✨ Key Features

Intuitive in-context WYSIWYG editing with drag-and-drop blocks, media manager, and auto-save drafts (enables quick content updates without code)
Advanced team collaboration: granular permissions, user groups, multi-step workflows, version history, and audit trails (perfect for enterprise teams)
Multisite and multilingual support with centralized dashboards, shared resources, and translation management (handles global or networked sites)
Built-in marketing and SEO tools: forms/CRM integration, XML sitemaps, social sharing, Open Graph, and analytics (drives engagement without add-ons)
Upcoming: Ongoing version 9.5.x enhancements, including better CI/CD and dependency updates

🛠 Tech Stack

Frontend: JavaScript, SCSS (5.1%), LESS, Bootstrap, responsive CSS
Backend: PHP (87.9%) with Composer for dependencies
Database: MySQL 5.7+, MariaDB
Auth: Built-in (users, groups, attributes, SSO support)
Hosting: Self-hosted (Apache/Nginx), Concrete Managed Hosting, Cloud providers

👥 Who Is This For?

This project is useful for:

Developers who want to extend and customize an open-source CMS with add-ons and themes
Teams looking for secure collaboration, workflows, and multisite management
Enterprises and agencies building compliant sites for government or business