And they're both ass tbh because the community edition for each one has arbitrary limitations built in, and you need a premium license to unlock its full capabilities.
UPDATE Feb 2, 2026: To be specific, our license is using standard open source licenses, a reciprocal AGPL license and a permissive Apache v2 license for other areas. Both are widely used open source licenses and have multiple interpretations of how they apply, as showcased in this thread.
When we say we don’t “offer the clarity the community would like to see”, that refers specifically to the many statements in this thread where different contributors are confused by other people’s comments and statements.
For LICENCE.txt itself, anyone can read the history file and see we haven’t materially changed it since the start of the project.
If you’re modifying the core source code under the reciprocal license you share those changes back to the open source community. If you’d like to modify the open source code base without sharing back to the community, you can request a commercial license for the code under commercial terms.
Sounds like you are allowed to do actual open source on the project, but mattermost might sell your work to others who don’t want to share their work back with the community. Which is a violation of the open source licenses, specifically the AGPL (I’m not certain on Apache?).
Sounds like a dick move, regardless of license violations.
It claims to be an open source alternative to Teams/Slack/etc. I thought Mattermost was pretty cool until I installed it, then I realized stuff like OIDC was locked behind a paywall and that is a requirement I rarely wave for things I run at home. After a bit of fighting I just abandoned it.
13 Comments
unexposedhazard@discuss.tchncs.de · 45 pts · 229d
Mattermost is dead. Just forget about it.
Eyekaytee@aussie.zone · 11 pts · 229d
damn they were like 1 of only 2 decent slack replacements
rocketchat being the other
9tr6gyp3@lemmy.world · 7 pts · 229d
And they're both ass tbh because the community edition for each one has arbitrary limitations built in, and you need a premium license to unlock its full capabilities.
vorpuni@tarte.nuage-libre.fr · 1 pts · 229d
Zulip works fine
Vulwsztyn@programming.dev · 2 pts · 211d
you could say it matters less
4am@lemmy.zip · 19 pts · 229d
Sounds like you are allowed to do actual open source on the project, but mattermost might sell your work to others who don’t want to share their work back with the community. Which is a violation of the open source licenses, specifically the AGPL (I’m not certain on Apache?).
Sounds like a dick move, regardless of license violations.
wtf is mattermost again?
BrikoX@lemmy.zip · 14 pts · 229d
Open core Discord/Slack/Matrix alternative.
stsquad@lemmy.ml · 4 pts · 229d
Do they also insist on a CLA so they can relicense contributions?
starshipwinepineapple@programming.dev · 5 pts · 229d
Yes there's a CLA
ITGuyLevi@programming.dev · 4 pts · 229d
It claims to be an open source alternative to Teams/Slack/etc. I thought Mattermost was pretty cool until I installed it, then I realized stuff like OIDC was locked behind a paywall and that is a requirement I rarely wave for things I run at home. After a bit of fighting I just abandoned it.
eleijeep@piefed.social · 13 pts · 229d
This would be easily solved by just forking the project. If they complain that a fork infringes their work then that is the clarification.
homesweethomeMrL@lemmy.world · 6 pts · 229d
Cool. Cool cool cool.
somegeek@programming.dev · 5 pts · 229d
Mattermost is indeed, a dick. They try to leech off of contributors like many of corporate focused open source products do.