I’m glad to announce that we have recently moved the documentation source repository to GitHub, under the free CC BY license. See https://github.com/cuba-platform/documentation.
The project contains all the docs for the platform core, Polymer UI and standard premium addons that you can see at https://www.cuba-platform.com/documentation
We will be grateful if you help us to improve the documentation by providing pull requests and reporting issues. If you see a spelling or wording mistake, a bug or inconsistency - please fork the repo and fix it. The README file contains instructions on how to build and view the docs locally.