Backdrop CMS is a free, open-source content management system for building websites. It is aimed at site owners who want an approachable administration interface without the complexity of larger platforms. Backdrop is a fork of Drupal 7 with a modernised codebase and a built-in upgrade path from Drupal 7. The software is written in PHP and is installed by the operator on its own web server. It is licensed under the GNU General Public License version 2 or later.
Backdrop CMS is a non-profit project of the Software Freedom Conservancy, a 501(c)(3) charity under US tax law, which holds the project's trademarks. No commercial company owns the project, so there is no foreign parent company to assess for CLOUD Act exposure. Because the code is GPL-licensed, a European organisation can run it on infrastructure of its choice within the EU and decide for itself where its data is stored.