Redis Labs had used Commons Clause on top of the open-source Apache License to protect its rights to modules added to its 3-Clause-BSD-licensed Redis, the popular open-source in-memory data structure store. But, as Manish Gupta, Redis Labs' CMO, explained, "It didn't work. Confusion reigned over whether or not the modules were open source. They're not open-source."
So, although it hadn't wanted to create a new license, that's what Redis Labs ended up doing.
RSAL covers some Redis Modules, which run on top of open-source Redis. The current modules covered by RSAL are: RedisSearch, RedisGraph, RedisJSON, RedisML, and RedisBloom. Redis remains under the BSD license.
The RSAL grants, Gupta said, equivalent rights to permissive open-source licenses for the vast majority of users. With the RSAL, developers can: Use the software; modify the source code; integrate it with an application; and use, distribute, support, or sell their application.
But -- and this is big -- the RSAL forbids you from using any application built with these modules in a database, a caching engine, a stream processing engine, a search engine, an indexing engine, or a machine learning/artificial intelligence serving engine. In short, all the ways that Redis Labs makes money from Redis. Gupta wants to make it perfectly clear: "We're not calling it open source. It's not."
At the same time, Redis Labs wants everyone to understand the new RSAL will have:
Zero effect on the Redis core license, which is and will always be licensed under the 3-Clause-BSD. Unlike many other open source database companies, we have built a dedicated team (led by Salvatore Sanfilippo, the creator of Redis), who manages the Redis core in a completely independent manner. Additionally, we have chosen not to limit the functionality of open source Redis by moving core components to closed source. Consequently, open source Redis includes all the ingredients needed to run a distributed database system -- replication, auto-failover, data-persistence and clustering.
Besides, Redis argues the RSAL doesn't target developers. Instead, as Redis Labs CEO, Ofer Bengal, recently put it, "Cloud companies [which] use their monopoly power to adopt any successful open-source project without contributing anything to it."
Redis added in their announcement, "other respected open source companies, like MongoDB and Confluent, created their own proposals for modern variants to open-source licensing. Each company took a different approach, but all shared the same goal — stopping cloud providers from taking successful open source projects that were developed by others, packaging them into proprietary services, and using their monopoly power to generate significant revenue streams."
Others don't buy this argument. Matt Asay, head of Adobe developer ecosystem, said:
It has become fashionable to call out the cloud vendors, and particularly AWS, as parasitic destroyers of open source value. What real-world contributor data actually tells us, however, is that this view of the clouds is completely wrong, at least at the macro level. Google and Microsoft are orders of magnitude bigger contributors to open source communities than any other company. Even AWS, which has perhaps correctly been criticized as not 'doing more', is one of the world's top-10 largest contributors, and has scaled up its contributions considerably in the last year. It would seem that more cloud tends to equate with more open source. Perhaps, then, the clouds are not the enemies of open source, but the best allies.
Gordon Haff, a Red Hat technology evangelist, pointed out recently that Redis' argument isn't new. In 2008, not long after Amazon Web Services (AWS) was founded, he saw the fear "companies will wholesale strip-mine Open Source projects." Despite Redis' arguments to the contrary, Haff doesn't believe that's the case. Instead, companies, including cloud businesses, are embracing open source not so much because of it lets you "view source code," but because of "its collaborative development model."
Haff went on: "A lot of the heat around licenses like the Commons Clause comes about because the companies involved seem to be, on the one hand, trying to gain the perceived value of a proprietary license while also getting credit for still being open source. 'Open core' arguably plays the same parlor trick."
Now that Redis has made it black and white that its new RSAL is not open source, while the Reddis code itself remains open source, perhaps the arguments will die down. In effect, what Redis is doing is putting its own license around the old open core business model.