// License
Sun’s license, in plain words
The engine is source-available under the Functional Source License (FSL-1.1-ALv2). The short version: use it, read it, change it. Just don’t sell it back to us as a hosted service.
Sun is in development. These terms apply from the first public release.
What you can do
- Self-host the full engine for free, as one binary on your own machine or server.
- No seat or run limits. SSO (OIDC) and roles are included.
- Read the code, change it and run your changed version.
- Build your own plugins and extensions with the public SDK, and keep them private or share them.
What you can’t do
- Sell Sun, or a copy of it, as a hosted service that competes with Sun.
What becomes fully open
- Each release of the engine becomes Apache-2.0 two years after it ships.
- The mod SDK and the runtime daemon are Apache-2.0 from day one.
What stays closed
- The Sun Cloud control plane and Sun credits billing.
- The marketplace and exclusive mods.
- Business features such as SCIM and audit export.
Why not MIT?
We want the code readable and free to run, and we also want to keep building Sun. FSL does both: it only blocks someone from reselling the engine as a rival cloud, and every release opens up fully after two years.