License
Sailfin is free and open-source software maintained by Sailfin, LLC.
The Compiler and Runtime
The Sailfin compiler, runtime, standard library, and supporting tooling code in the SailfinIO/sailfin repository are licensed under the GNU General Public License, version 2 (GPLv2). Trademarked brand assets (such as the logo, mascot, and favicon) are not covered by the GPLv2 and are governed by the Trademark Policy.
This means you are free to use, study, modify, and redistribute Sailfin. If you distribute a modified version of the compiler or runtime, your modifications must also be made available under the GPLv2. This ensures that Sailfin and all derivative works remain open source.
Your Programs Are Yours
The Sailfin runtime libraries include a Runtime Library Exception modeled after the approach used by GCC. This exception means that programs you compile with Sailfin are not subject to the GPL.
You can write Sailfin programs, compile them, and distribute the resulting binaries under any license you choose — including proprietary licenses. The runtime exception ensures that linking against the Sailfin prelude and standard library does not create a copyleft obligation on your code.
What This Means in Practice
You can
- Use Sailfin for any purpose, commercial or personal
- Write proprietary programs in Sailfin and sell them
- Fork the compiler and modify it
- Distribute the compiler and runtime
- Contribute to the project
You must
- Keep the GPL license on the compiler and runtime source
- Share source code if you distribute a modified compiler or runtime
- Preserve copyright notices and attribution
Contributing
By contributing to Sailfin, you agree that your contributions will be licensed under the GPLv2. See the contributor guide for details.
Questions
If you have questions about Sailfin's licensing, please open an issue on GitHub.