Bit Phoenix Projects
Bit Phoenix Projects, codenamed Project: Cassian, is our free and open-source collaborative game design platform. It allows creation of public and private projects, the ability to edit a game design document in an easy-to-use tree-like interface, task management, the ability to add developers and admins to projects, a RESTful JSON API for integrating with other pieces of software, and more.
The source code for both the front-end UI and back-end JSON API are freely available on GitHub. You can use, modify, contribute to and deploy either one of these.