RobustMQ is licensed under the Apache License 2.0. You are free to use, modify, and distribute RobustMQ for any purpose, including commercial use.
We require all contributors to sign a Contributor License Agreement (CLA) before we can accept contributions. The CLA ensures that we have the necessary rights to distribute your contributions under the project's license. The CLA also guarantees that your contributions are always licensed back to you under the terms of the license in effect at the time of your contribution.
RobustMQ is a long-term project. Building and maintaining a production-grade, multi-protocol unified messaging engine requires sustained investment in engineering, testing, documentation, and community support.
To protect the long-term sustainability of this project, we may in the future change the license to the Business Source License (BSL) 1.1. Under BSL, each version of the code automatically converts to a fully open source license (Apache 2.0) after a defined period, typically 4 years.
We want to be transparent about this possibility upfront, rather than making a surprise change later.
Enterprise and individual users: If you are using RobustMQ internally — in your own applications, services, products, or infrastructure — nothing will change. You can continue to use, modify, and deploy RobustMQ freely, with no restrictions, under any license we adopt. This applies to the vast majority of our users.
Cloud providers and service vendors: If you intend to offer RobustMQ itself as a commercial hosted messaging service or embed it in a commercial product sold to third parties, a commercial license may be required under a future BSL license.
Contributors: The CLA you sign ensures that we can make license changes when necessary, while guaranteeing that your contributions remain available to you under the license in effect when you made them.
In short: Our intention is to prevent cloud providers from taking RobustMQ and offering it as a competing commercial service without contributing back. For 99.999% of users, any future license change will not affect you at all.
We believe in transparency. Many open source projects have changed their licenses without prior communication, causing confusion and eroding trust. We would rather be upfront about our plans from day one, so that every user, contributor, and partner can make informed decisions with full knowledge of our direction.
This is not a commitment to change the license — it is a commitment to honesty about the possibility.
If you have any questions about licensing, please open an issue or reach out to us directly.