Stan is open source because we want your contributions to help make Stan’s code and documentation better.

Suggest or Discuss Code Patches

To suggest or discuss patches, such as localized bug fixes, the Stan Forums is the best venue.

More extensive discussion about development is limited to the Developer category of the forums. While everyone can read all discussion in the Developer category, only users that have been added to the developer group can create posts or reply to existing posts.

If you would like to be considered for the developer group then you can request access in any ongoing discussion in which you are participating.

Contribute Code Patches

If you’d like to contribute code, please submit it through a GitHub pull request. The developer process for creating a GitHub pull request is described on the Stan Wiki.

After code review, testing, and merging, all code is distributed under the same open-source license of the package to which it belongs (GPL for RStan, PyStan; BSD for CmdStan, C++ API; CC BY for documentation).

To Do List and Projects

Larger project design documents and goals, as well as the developer process followed by Stan, are listed in various places on:

Join the Development Team

The Stan development team is always looking for developers willing to get their hands dirty with C++, R, or Python design, coding, documentation, testing, and maintenance.

The current list of bugs and feature requests we would like to implement is available on the interface-specific issue trackers.

If you’d like to join the development team and gain push access to the Stan code repository, please let us know by first creating a post in the Project Proposals category of the Stan Forums. Be sure to include a brief description of your programming background and details of what you’d like to contribute.

Source Repositories

Stan’s source is managed through the Git version control system and hosted by GitHub. All of the source repositories, including the math library, Stan’s core API (language and inference), and all of the interfaces, add-ons, and example models are listed here: