Concrete CMS is an open source content management system where editing happens on the page: editors click the page and change it, where it is. No admin-panel maze, no preview round-trips. This page is the case for building on it, and who it is for.
Log in, click any block, edit it in place. Drag blocks between areas and see exactly what visitors will see. Site handoffs fail in the gap between "developer builds it" and "client maintains it", and Concrete closes that gap better than anything else we have used.
Every page edit creates a new version, content and layout together, and old versions stay available to compare, restore or schedule. It is core behaviour, and it covers the stacks and global areas that make up the shared parts of a site.
Concrete ships with a simple permissions model and an advanced one you switch on when you need it. Advanced gives you per-page, per-area and per-block permissions with user groups, plus workflow approval for an editorial chain. This is the feature that wins agencies: the marketing team edits news, legal approves policy pages, nobody touches the homepage.
Forms, image galleries and sliders, page lists, search, SEO basics, multilingual sites, and a file manager with its own permissions are all in core and maintained by the core team, instead of a plugin stack from a dozen vendors on a dozen update schedules.
The core is MIT licensed. Self-host it anywhere PHP and MySQL run. The company behind it, PortlandLabs, sells hosting and support, and does not sell licence keys for your own site.
Monthly releases, published security fixes, PHP 8.5 support, and Twig templating in 9.5. Version 8 is end of life and no longer receives security fixes.
Concrete's community is small compared to WordPress: fewer add-ons, fewer themes, fewer tutorials. That is the trade for a coherent core, and it is why this site exists. If you need a niche integration that already exists as an off-the-shelf plugin elsewhere, WordPress may serve you better. If you want a solid editable site without a plugin stack to babysit, Concrete is a better fit than its market share suggests.