ProjectEdit on GitHubSource: LICENSING.md

Licensing

Kshana is dual-licensed. You may use the open engine under either the open licence (AGPL-3.0) or a commercial licence from Ashforde OÜ. Pick the one that fits how you intend to use it.

This document explains the model in plain language. It is a guide, not legal advice, and it does not modify the licences themselves. The binding terms are in LICENSE (the GNU AGPL-3.0) and in any commercial agreement you sign with Ashforde OÜ. If the two ever conflict, those documents govern.

Option A — open source: GNU AGPL-3.0-only#

The default. The full text is in LICENSE. In short, the AGPL lets you use, study, modify, and redistribute Kshana for free, provided that:

  • if you distribute Kshana or a derivative, you make the complete corresponding source available under the AGPL; and
  • if you let users interact with a modified Kshana over a network (the AGPL's distinguishing clause, §13), you must offer those users the corresponding source of your modified version under the AGPL.

AGPL is an OSI-approved open-source licence and strong copyleft. It is the right choice for academic work, open-source projects, internal evaluation and research, and anyone happy to keep their own derivative open.

Option B — commercial licence (from Ashforde OÜ)#

If the AGPL does not suit you, Ashforde OÜ will license the same engine under commercial terms. This is the right choice when you want to:

  • embed Kshana in a proprietary / closed-source product without releasing your own source;
  • offer a network service built on a modified Kshana without the §13 source-disclosure obligation;
  • integrate Kshana into a larger system whose other components cannot be AGPL (e.g. a prime contractor's proprietary toolchain); or
  • obtain a warranty, indemnity, or support terms the AGPL explicitly disclaims.

A commercial licence removes the copyleft obligations for your use, on agreed terms. Contact: contact@ashforde.org.

Why dual-license this way#

The goal is to be publicly verifiable (so any reviewer can run and audit the engine) without letting a well-resourced competitor fork the validated engine, close it, and ship a proprietary competitor that gives nothing back. AGPL's network copyleft achieves that: a closed or hosted derivative must come back to open source — or take a commercial licence from us. Public credibility and a defended core, at the same time.

What is not covered by this dual-license#

  • Kshana Pro and other proprietary overlays are separate, closed-source products under their own commercial terms. They are not part of this repository and are not offered under the AGPL.
  • Dependencies keep their own (permissive) licences. We deliberately keep the dependency tree permissive (Apache-2.0 / MIT / BSD / ISC / …) precisely so the commercial edition can be offered cleanly — a copyleft dependency would taint it. See deny.toml.
  • Trademarks. "Kshana" and its marks are trademarks of Ashforde OÜ. Neither licence grants rights to the name or marks; forks and derivative distributions must use a different name. See NOTICE.

Contributions#

Contributions are accepted under the project's inbound contributor terms, which license your contribution under the AGPL and grant Ashforde OÜ the right to include it in the commercially-licensed edition (so the dual-license keeps working). See CONTRIBUTING.md.

Questions#

Licensing questions, commercial quotes, and "which option applies to us?" → contact@ashforde.org.