About the license #

Redict is distributed using the Lesser GNU General Public License, aka LGPL-3.0-only, and is based on the Redis®¹ OSS 7.2.4 3-Clause BSD licensed source code.

LGPL is a copyleft license. The following is no substitute for the advice of a lawyer, particularly in more complex scenarios, but it suffices to summarize the basic functions of this license for those unfamiliar with the concept.

Tip: Commercial and non-commercial users of Redict are not required to publish or otherwise “open source” the source code of Redict, including any private modifications they make to the source code, nor are they required to publish the source code of any software they use in combination with Redict.

Use-cases which require publishing changes #

If you compile Redict’s source code into an executable form and distribute this executable form to others you are required to include a copy of the Redict source code and any modifications to it licensed under the LGPL.

Users who wish to distribute modified versions of Redict to the general public are encouraged to simply use the same LGPL license and include the source code with your modified versions. It is possible to avoid using the LGPL on some derived works, but this requires special considerations that are beyond the scope of this documentation. In this case, please read the license carefully and possibly consult a copyright lawyer to ensure compliance.

FAQ #

Why the LGPL for Redict? #

The use of the LGPL is a permanent, irrevocable promise that Redict will always be free software. By using a copyleft license, all changes to Redict are required to be distributed using the same LGPL free software license, guaranteeing that modified versions of the software will be free.

We do not make use of any sort of Contributor License Agreement to give one entity special privileges with respect to the copyright and licensing of Redict. The copyright of Redict is held in common by all contributors, who would all have to agree to a future change of license.

Are Redict Modules (or Redis® Modules) compatible with the LGPL? #

Redict Modules and compatible Redis® Modules are able to be used with Redict regardless of the license of the module in question.

Are my Lua plugins compatible with the LGPL? #

Lua plugins and scripts for Redict are not required to make any special considerations with respect to the LGPL, regardless of the license used for the Lua plugins.

Can I use Redict as part of a commercial product? #

Yes, you can use Redict as the basis of a commercial offering, modified or otherwise, without any special steps for compliance with the license, provided that you do not distribute Redict or modified versions of Redict to users in executable form.

For example, using Redict as the database backend for a commercial web service, or offering Redict databases as a service to your customers, does not require you to disclose the source code of Redict, modified or otherwise.

What is Redict’s licensing relationship to Redis® OSS? #

Redict is a fork of Redis® OSS 7.2.4, which is distributed under the terms of the permissive BSD 3-Clause license. All changes made by Redict on top of the original Redis® OSS source are licensed under LGPL-3.0-only.

Redict is compatible with the REUSE specification, which provides insights into the provenance of and licenses involved in the project and to what extent they apply to various parts of the software.

Are you allowed to change the license of Redis® OSS to LGPL? #

Yes. Redis® OSS used the 3-Clause BSD license, which is a permissive license that allows sublicensing provided that its terms are met. Redict is fully compliant with the 3-Clause BSD license used by the included Redis® OSS source code.

Redis® Ltd, the company responsible for Redis® SAL, does not hold the copyright to Redis® OSS. Their commercial offering is sublicensing Redis® OSS in a similar manner as Redict does, only where Redict is free software using the LGPL, Redis® SAL is using the proprietary SSPL and RSAL licenses.

Why LGPL-3.0-only rather than LGPL-3.0-or-later? #

The use of LGPL-3.0-only makes the licensing situation with respect to Redict fixed for the indefinite future, and does not provide an opportunity for a sole entity (the FSF, in this case) to unilaterally change the license terms. While there are arguable advantages to using LGPL-3.0-or-later, it was decided that this approach was more favorable for Redict’s purposes.