ProcessWire is a free PHP open source CMS with a great API built to save you time and make development fun at any scale. Developed by Ryan Cramer Design, LLC
License: Open Source
ProcessWire is a robust and flexible CMS ideal for developers looking for customization and powerful features, while GetSimple CMS is a lightweight and user-friendly option best suited for small websites or users with minimal technical skills. The choice between the two largely depends on the project's complexity and the user's technical expertise.