Mattermost
Mattermost is an open source alternative to Slack.
Mattermost is an open source, self-hosted 
Slack alternative.
As an alternative to proprietary SaaS messaging, Mattermost brings all your team communication into one place, making it searchable and accessible anywhere. It’s written in Golang and React and runs as a production-ready Linux binary under an MIT license with either MySQL or Postgres.
Mattermost is:
Slack-compatible, not Slack-limited – Mattermost features rival Slack features, and support a superset of Slack’s incoming and outgoing webhook integrations, including compatibility with existing Slack integrations. From your existing Slack teams, you can import users, public channel history and even theme setting colors into Mattermost.
Mobile and desktop apps, in addition to web – Use Mattermost from your iOS or Android phones and tablets or with installed apps on Windows, Linux and Mac.
Easy to deploy, manage, and upgrade – Mattermost runs as Linux binary, Docker image, and many other forms. Try Mattermost with a one-line Docker install, and many install guides are available. Improvements ship monthly.
Supported by a vibrant community – Use Mattermost with dozens of community integrations and applications, including Jira, IRC, XMPP, Hubot, Giphy, Jenkins, GitLab, Trac, Redmine, SVN, RSS/Atom and many others. Build and share your own apps using Mattermost APIs and drivers.
Slack alternative.As an alternative to proprietary SaaS messaging, Mattermost brings all your team communication into one place, making it searchable and accessible anywhere. It’s written in Golang and React and runs as a production-ready Linux binary under an MIT license with either MySQL or Postgres.
Mattermost is:
Slack-compatible, not Slack-limited – Mattermost features rival Slack features, and support a superset of Slack’s incoming and outgoing webhook integrations, including compatibility with existing Slack integrations. From your existing Slack teams, you can import users, public channel history and even theme setting colors into Mattermost.
Mobile and desktop apps, in addition to web – Use Mattermost from your iOS or Android phones and tablets or with installed apps on Windows, Linux and Mac.
Easy to deploy, manage, and upgrade – Mattermost runs as Linux binary, Docker image, and many other forms. Try Mattermost with a one-line Docker install, and many install guides are available. Improvements ship monthly.
Supported by a vibrant community – Use Mattermost with dozens of community integrations and applications, including Jira, IRC, XMPP, Hubot, Giphy, Jenkins, GitLab, Trac, Redmine, SVN, RSS/Atom and many others. Build and share your own apps using Mattermost APIs and drivers.
Comments and Reviews
Categories
Social & Communications • Development • File Sharing • Office & Productivity • Remote Work & Education • Security & PrivacyTags
- Plugin Marketplace
- access-from-everywhere
- Chat Rooms
- javascript
- go-lang
- team-communication
GitLab officially integrates Mattermost in its deployment packages. Providing a single sign-on for users of both applications.
http://docs.gitlab.com/omnibus/gitlab-mattermost/
Open source slack knock off. Slack already sucks, this sucks even more, though at least it's more open.
There's no good Linux client. Of the only ones that are actually usable one was a bloated electron monstrosity, the other wants access to create a second account on their own server and feed all your instant messages to them. Lol! Needless to say I ended up using the first one.
All this program is, is a glorified chatroom. IRC does the same thing a million times better, without the onerous account system and the pathetic selection of clients. The chat interface itself is a mess, cluttered with things like dates, needless separators, ugly icons and emojis. One of their "features" is that you can put emojis on people's chat messages, like in Github images. Who the hell needs to pin emojis on chats? Just reply with the emoji if you really have to.
Godawful program, but unfortunately your boss will require to use it. Oh well, at least it's not slack...
It's not a slack alternative, it's far more better. I personally love the native markdown support.
Trying to post a review ...last one ended up in "comments" section as double post
I would not advise to install it - !!!
Software is too simple no image display , no nothing ...but what it does have is a tracking
if you try to remove it - server wont start - coz its always connecting to a third party sites:
cdn.rudderlabs.com
cdn.segment.com/analytics.js
Avoid this software !!!
Does not support voice (or video for that matter) calls natively; you need a third-party plugin for that. I guess it supports it somehow?