The first pass at Concrete5 5.7 Developer Documentation is now available. This includes background, a full glossary, installation and upgrade information, request and dispatcher lifecycle information and our complete theming guidelines. These theming guidelines contain three new screencasts, detailing theme package creation, custom grid framework creation, and the complete process by which you can make your Concrete5 themes customizable.

5.7 Developer Documentation

There's much more to come, and you can see the roadmap on the documentation page.