We welcome other developers who wish to get involved in supporting and enhancing this software.

Permissions Granted by the OFL

SIL’s Latin, Cyrillic and Greek fonts are licensed according to the terms of the SIL Open Font License. For specific information on permissions granted by the OFL, such as freedom to make your own versions or the freedom to bundle, see the OFL FAQ.

Source Code

The source code for the latest version is available in the “developer” package on the Download page for each font.

Future Development

In the future, the source will be in a GitHub project and will contain information on how to set up your development environment. We are in the process of converting the design files from a FontLab (VFB) format into a Unified Font Object (UFO) format. We also intend to use GitHub’s issue tracking mechanisms.

Copyright attribution

If you submit something for inclusion in the main fonts, we will ask you to affirm that it is your original work, and ask you to assign the copyright of your work to SIL International. This is to ensure that future releases can be made under improved versions of the OFL without needing to track you down for further permission. This follows the same principle used by the Free Software Foundation (FSF). Keep in mind that we are a not-for-profit organization committed to free/libre and open source software, and that any contributions incorporated in the fonts will always be available under the OFL or a similar license.


Because we want to be able to guarantee a high level of quality for our fonts, we will review submissions carefully. Please don’t be discouraged if we do not include a submission for this reason, or ask you to make specific revisions.

Note to Contributors

Contributions that would be welcomed now (some more than others):

  • Old style figures
  • Coptic
  • Historic/Archaic Cyrillic
  • Mathematical glyphs
  • OpenType code and glyphs for on-the-fly fraction creation
  • Additional scripts (Armenian, etc.?), and any needed OT/Graphite code


If you would like to contact the development team, please use the Contact Form.