While Commlink is mainly developed by a single developer, the project is open to contributions. The source code and data is publically available, to give everyone interested in contributing a chance to make him-/herself familiar - it is however not open source.
The main developer made contracts with a publisher that allows including copyrighted material. That means the project as a whole can not be open sourced. It also means that the main developer gets a minor pay from sold licenses.
We still consider us an open community. We value your contribution and promise to make them available for the community and not put your contributions behind a paywall, but you needed to know this before putting effort in this project.
Now, here are some things you might want to know: