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Below you find the licenses which apply to Crossbar.io source code and documentation.

Crossbar.io Code License


The Crossbar.io source code is licensed under the GNU AGPL 3.0. You can find a copy of the license in the repository here and references to this license at the top of each source code file.

All rights to the Crossbar.io source code remain exclusively with Tavendo. All external contributors need to sign a contributor assignment agreement (CAA) when contributing to the project.

The Crossbar.io application templates and instances of code generated from these templates are licensed under the BSD 2-clause license.

WAMP clients as separate works

We see any code which connects to Crossbar.io via WAMP as a separate work. The Crossbar.io license (the AGPL v3) does not apply to WAMP clients. This applies irrespective of where these run, i.e. also to components which are run side-by-side within an native worker of type router, which are run in a native worker of type container or in a guest worker. We promise to stand by this view of the license. If you need further assurance, you can email us at service@tavendo.de for a signed letter asserting the above promise.

We release all our client libraries (those provided by the Autobahn project under non-copyleft licenses, which allow their use for closed-source & commercial software. For other client libraries see their respective licenses (these appear to be universally non-copyleft as well).

Crossbar.io Documentation License

Copyright for the Crossbar.io documentation (C) Tavendo GmbH. Licensed under the Creative Commons CC-BY-SA 4.0 license.

"WAMP", "Crossbar.io" and "Tavendo" are trademarks of Tavendo GmbH.

This license allows you to use the material in this documentation, whole or in parts, in its present form or adapted, and for any purpose (including commercial use), as long as you

  • attribute the material to us giving the information provided below and
  • share the material under this same license

For more details (and the legally binding conditions) see the Creative Commons license page for this license.

Attribution details:

(C) by Tavendo GmbH, material licensed under the CC-BY-SA 4.0, provided as-is without any warranties, Crossbar.io documentation wiki

Note to Contributors to this documentation

By contributing, you accept that the above license applies to your contribution.