[[!meta title="Licenses"]]

[four freedoms]: https://www.gnu.org/philosophy/free-sw.html
[GNU General Public Licence, version 3 or later]: https://www.gnu.org/licenses/gpl-3.0.html
[Apache 2.0]: https://www.apache.org/licenses/LICENSE-2.0
[CC-BY-SA 4.0 (International)]: https://creativecommons.org/licenses/by-sa/4.0/

We have chosen software licenses for this project following these
principles:

* Subplot itself is free software, meaning it provides all the [four
  freedoms][] as defined by the Free Software Foundation: use (for
  whatever purpose), study and change, share, share modified versions.

* Subplot should have little effect on the licensing of the outputs.

While we would prefer it if everyone only produced free software, we
don't want to mandate it, and thus we've chosen to use a mix of
permissive and copyleft licenses for different parts of the project.

As long as you only run Subplot, you don't need to care about the
licences, and you can use the outputs as you wish.

* The Subplot tooling (document and test program generators) are
  licensed under the [GNU General Public Licence, version 3 or
  later][].

* The documents and test programs generated by Subplot have whatever
  licence the input documents have. Subplot has no effect on their
  licences.

* Subplot uses templates, libraries, and scaffolding to produce the
  test programs. These are licensed under the [Apache 2.0][] licence,
  but with the extra permission that when they're used to generate
  outputs by Subplot, they don't affect the licence of the generated
  test programs. The programs generated by Subplot have the license of
  the inputs.

* The Subplot documentation, inluding examples, are licensed under the
  [CC-BY-SA 4.0 (International)][] licence. This is better suited for
  documentation than the code licences above.