[hannob]

It is a bit unusual, but ultimately it's similar to the quite common "you can have the code under AGPL or negotiate something else with us" plus something unusual, i.e. a MIT-licensed binary.

Ultimately if you're okay with running AGPL code you're okay with running Mattermost. Which means as long as you don't intend to fork it and not share your changes you should be fine.

[pksadiq]

> Ultimately if you're okay with running AGPL code you're okay with running Mattermost. Which means as long as you don't intend to fork it and not share your changes you should be fine.

That's not how [LA]GPL works. You are free to fork, and not share the changes. The modified source code can be provided only to the people whom you gave the binary (Edit: AGPL has bit more terms, as said in comment below), and you can make it private to the rest of the world (though you can't add additional restrictions).

As Mattermost is dual licensed under AGPL, anyone who uses it under the terms of AGPL can live safe as long as they obey AGPL.

Software pieces using GPL licenses can't add additional restrictions to the software, but of course authors are free to dual license under different terms.

Say for example some one can specify the following for their project: "We provides the project under the terms of MIT for you to modify and run for your own purposes." This might look a harmless statement, but it could mean something very different and may be intentionally written, that essentially makes it non-free. GPL doesn't allow such additional clauses.

Disclosure: IANAL. So I don't know how/if it works in court

[zwily]

> AGPLv3 requires a program to offer source code to “all users interacting with it remotely through a computer network.” It doesn't matter if you call the program a “client” or a “server,” the question you need to ask is whether or not there is a reasonable expectation that a person will be interacting with the program remotely over a network.

From https://www.gnu.org/licenses/gpl-faq.html#AGPLv3ServerAsUser

[contravariant]

Forgive me if I'm wrong but wouldn't you be allowed to fork it and not share your changes anyway? As far as I know a copyright license is only required if you do share it.

Of course you couldn't share any derived binaries without a valid copyright license, but for internal use there shouldn't be any problem.

[greenshackle2]

There might be problems even for internal use because it's licensed under AGPL not just GPL, so the source must be distributed to network users, even if you don't share the binaries with them.

It might work for your company's internal chatroom but not for selling Mattermost as a service.

That's the intention anyway, I'm not a lawyer, I don't know if AGPL was tested in court, and whether it would hold up.

[theturtletalks]

So if I understand correctly, AGPL allows single users to use the software but they cannot provide this software as a service? I've also seem some open source SaaS offer a dual license for single users and corporations. MIT or Apache for single users and GPL for corporations.

[greenshackle2]

You can provide the software as a service BUT you have to give the source code to all users, including your modifications if you have made any.

In other words - you can't sell SaaS based on AGPL software + proprietary secret sauce, you have to share back your secret sauce with all users.

It doesn't prevent you from selling it as SaaS, I could sell vanilla Mattermost as a service under AGPL, my selling point might be that I provide high reliability and excellent support.

Do you have an example of that dual license?

I don't see how that would work, the first person you give an MIT license to can re-distribute it under MIT to anyone else, including corporations.

Usually for dual-license you have the opposite, you would have a restrictive license like AGPL for the public, and you would sell non-free licenses with no redistribution rights that allow modifications without sharing back, for corporate clients who want to add their secret sauce to the software without having to give away the secret sauce for free.