Round Robin Software License 2.0.0


This license lets you use and share this software for free. You can license your applications however you like, but you have to contribute changes, additions, and other software that builds on this software back on similar terms.


To receive this license, you have to agree to its rules. Those rules are both obligations under that agreement and conditions to your license. Don’t do anything with this software against any rule you can’t or won’t follow.


Give the text of this license or a link to to everyone who gets a copy of any part of this software from you, along with information making clear this license applies to the software.


With two exceptions, Prototypes and Applications, contribute all changes and additions you make to this software, as well as all software that invokes this software’s functionality. When in doubt, contribute.


You don’t have to contribute any change, addition, or other software that meets all these criteria:

  1. You don’t use it for more than thirty days.

  2. You don’t share it outside the team developing it, other than for non-production user testing.

  3. You don’t use it on behalf of anyone outside the team developing it.


You don’t have to contribute any software that only invokes this software’s functionality through the interfaces this software exposes, unless it exposes so much of this software’s interfaces or functionality to users, programmers, or other software that it becomes a practical substitute for this software for any substantial portion of its use cases. Interfaces exposed by this software include all the interfaces this software provides users, programmers, or other software to invoke its functionality, such as command line, graphical, application programming, remote procedure call, and inter-process communication interfaces.


To contribute software:

  1. Publish all source code for the software in the preferred form for making changes through a freely accessible distribution system widely used for similar source code, so other contributors and users can find and copy it.

  2. Make sure every part of the source code is available under this license, the Blue Oak Model License 1.0.0, or terms with substantially the same legal effect. You can include source code licensed by others under the MIT License, two-clause BSD License, BSD-2-Clause Plus Patent License, Apache License Version 2.0, or similar terms that give less certainty about patents, so long as the developers of the source code don’t mention that patents apply or might apply to the software in code comments, documentation, or legal notices, and you aren’t aware of any such patents yourself.

  3. Take these steps within thirty days.

  4. Note that this license doesn’t let you change the license for this software. Follow Notices.


You’re excused for unknowingly breaking Copyleft if you contribute as required, or stop doing anything requiring this license, within thirty days of learning you broke the rule. You’re excused for unknowingly breaking Notices if you take all practical steps to comply within thirty days of learning you broke the rule.

Each contributor licenses you to do everything with this software that would otherwise infringe their copyright in it.


Each contributor licenses you to do everything with this software that would otherwise infringe any patent claims they can license or become able to license.


No contributor can revoke this license.

No Liability

As far as the law allows, this software comes as is, without any warranty or condition, and no contributor will be liable to anyone for any damages related to this software or this license, under any kind of legal claim.