Hey there,
I’m on the search for an alternative to Mattermost for a small institution I’m working with. Mattermost was the strongest contender for our needs, yet they changed their policy regarding self-hosted instances. The factor that killed it for us, is the hard cap on 250 registered users, as we potentially might need to commodate more than that.
Rocket.Chat has similar caps.
We found Zulip, and it seems as it might be what we are looking for, but we haven’t tested yet. Nonetheless, I wanted to address this community, as you may have another good idea?
I’m in the same boat, running a Gitlab Mattermost instance for a small team.
Gitlab has not announced yet what will happen with the bundled Mattermost, but I guess it will be dropped entirely, or be hit by the new limitations (what will hit us the hardest is the 10000-most-recent messages limitation, anything further than that will be hidden behind a paywall - including messages sent before the new limitations come in effect - borderline ransomware if you ask me)
I know there are forks that remove the limitation, may end up doing that if the migration path is not too rough.
I used to run a Rocket.Chat instance for another org, became open-core bullshit as well. I’m done with this stuff.
I have a small, non-federated personal Matrix + Element instance that barely gets any use (but allows me to get a feeling of what it can do) - I don’t like it one bit. The tech stack is weird, the Element frontend receives constant updates/new releases that are painful to keep up with, and more importantly, UX is confusing and bad.
So I think I’ll end up switching this one for a XMPP server. Haven’t decided which one or which components around it precisely. I used to run prosody with thick clients a whiiille ago and it was OK. Nextcloud Talk might also work.
My needs are simple, group channels, 1-to-1 chat, posting files to a channel. ideally temporary many-to-many chats, decent web UI.
Voice capabilities would be a bonus (I run and use a mumble server and it absolutely rules once you’ve configured the client, but it doesn’t integrate properly into anything else, and no web UI), as well as some kind of integration with my Jitsi Meet instance. E2E encryption nice but not mandatory. Semi-decent mobile clients would be nice.
For now, wait and see.
Is XMPP not good enough ? Or GNU-Jami.
Any recommendations for a good XMPP web client?
See my requirements in other comment.
Movim & Gajim. Dino is pretty good too
Acronyms, initialisms, abbreviations, contractions, and other phrases which expand to something larger, that I’ve seen in this thread:
Fewer Letters More Letters IMAP Internet Message Access Protocol for email SMTP Simple Mail Transfer Protocol SSO Single Sign-On XMPP Extensible Messaging and Presence Protocol (‘Jabber’) for open instant messaging
4 acronyms in this thread; the most compressed thread commented on today has 4 acronyms.
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You can try Delta Chat. It’s self hosted, E2EE and they use SMTP and IMAP protocols, so it’s compatible with any email account (not 100% real this, didn’t work with tutamail or Proton mail)
I tried Zulip for a small org. Used their hosted version since it’s quite generous for nonprofits. I personally liked it, but I was very much in the minority. Most of our people didn’t like it. I don’t think anyone articulated very well why they didn’t like it so it’s hard for me to characterize it other than people bitched about the UI a lot. I personally think it works fine, just be ready for some pushback.
We also tried Mattermost, and the uptake seemed a little easier. If you’re used to slack, discord, etc., most of them are pretty easy to transition to, but if you’re dealing with people that never used a real time chat platform, all of them (even slack) are like pushing a rock uphill because people can be impressively resistant to sensible change.
Nextcloud talk, but it’s no small feat to setup properly
This sounds like exactly my research arc over the last few months. I went with rocket because the 50 user limit is probably fine… Doesnt work with podman regardless of the docs.
Curious to see where you land
People suggest matrix but matrix really doesnt replace mattermost for an org.
mattermost is oriented towards org needs. It has boards, playbooks, better levels of access control. Admin panels etc.
We really need a sane Slack alternative that is at least fully free for self hosting.
Mattermost is licensed under the AGPL. How are they enforcing a 250 user limit?
Edit: the commercial version with additional features (e.g.: SSO) is limited. Obviously the open-source version is unlimited.
Might be worth reading this and the original github issue. It isn’t actually agpl. They only grant access to the source code to build a compiled version which isn’t freedom. And beyond that, some code is covered under a source available enterprise license which i think is where they would enforce their paywall
At the copyright owner, they are within their rights to release the source code under the AGPL, and also sell it under other licenses. Anyone is free to use the code under the AGPL. Nobody who releases code under an open-source license is obligated to provide binaries.
As the copyright owner, they are free to use the code along with other non-open-source code (e.g.: SSO integrations) to build a non-free product.
I feel like you didn’t read the post or issue i linked, nor their license.txt and are instead just trying to talk past me.
I don’t really care about this project or debating their intentionally ambiguous license structure. My point was that the grant of rights explicitly only grants AGPL access to create compiled versions of mattermost. That is not how FOSS licenses work and is incompatible with FOSS licenses because it lacks the “freedom” that even AGPL would typically grant.
You may be licensed to use source code to create compiled versions not produced by Mattermost, Inc. in one of two ways:
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Under the Free Software Foundation’s GNU AGPL v3.0, subject to the exceptions outlined in this policy; or
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Under a commercial license available from Mattermost, Inc. by contacting commercial@mattermost.com
I’m not saying that people can’t dual license or that they can’t release their product in other non-free ways. That’s not the issue here. The issue is that you are saying it’s AGPL, and it’s not–Not really. It’s only AGPL to create a compiled version of mattermost.
IANAL. I originally interpreted the license.txt as: all of the source code is AGPL (see lines 234-235), some of the source is also Apache 2.0, and the binaries are MIT; plus a trademark notice and contact info for getting a commercial license. After rereading it, my only conclusion is that this is a dumpster fire of a license.txt, and can be reasonably read several different ways.
And, people have been asking them to clarify it and they just say, “no.”
They’re acting very suspiciously.
Agreed, very suspicious. I would feel safe assuming that I can use the code under AGPL, but I would hesitate to use it for anything other than personal hobby because it would not surprise me if they closed their github account and never released any more code.
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Some drama on their licensing situation:
https://github.com/mattermost/mattermost/issues/8886#issuecomment-3837091846
Matrix (Synapse with Element) can be self-hosted for free, though they have optional paid plans for enterprises. The main goal of Matrix is federation (connecting with other servers), though this can be turned off completely. This is probably the most “business” look/feel you can get fully FOSS, if that’s what you’re looking for.
XMPP has more clients/servers, and is more for the technically oriented end user. I can’t really give recommendations here, as I haven’t extensively used XMPP.
Spacebar (formerly Fosscord) is a Discord clone (API compatibility as a goal) that can be selfhosted.
Xmpp works great for 1:1 chats and small private groups, but there isn’t really an enterprise team chat client for it. Recently some promising projects came up trying to change that, but they are still too new to be serious contenders for that usecase specifically. Maybe in 1-2 years the situation will be different.
Using matrix through element.io on ocassion.
It’s great.Had to move a small team away from skype/teams quickly so renting dedicated matrix hosting in Europe and not federating the instance has been working great, except for some issues like group calls over jitsi not working properly and users reluctant to learn more odd interfaces.
I keep seeing Zulip tossed around as an alternative, but I don’t know what’s up with their licencing. There’s also Framateam, but I think that might just be Mattermost as a service.
Matrix would be great if it wasnt so user-hostile, but it is :-(
Zulip is great, it’s very powerful and works well even when you rely on their hosting. The only issue I have with it is its ui could be better but its not something you can’t figure out. Search feature isn’t always the most reliable so that practise isn’t gonna work there.
Out of curiosity would matrix work for you?
A Matrix server is a good solution. You can disable federation if you would rather not talk to other instances and have a similar experience to Mattermost, Slack, etc.
If you dislike the Matrix protocol, an XMPP server would work exactly the same way.
NextCloud Chat could also be a viable solution for internal chat.
There is also Nextcloud Talk, but it can be a bit overwhelming to set up (needs the high-performance backend for video and stuff). But, it’s entirely self-hosted and has no user cap as far as I am aware.
I’m not sure what the performance would look like for hundreds of users
















