Alternatives to Slack for Self-hosting with any license

Riot.im

Riot (formerly Vector) is an opensource interoperable app running on Web, iOS and Android. It is built around chat rooms, both public and private and provides messaging...
- decentralised, federated, end-to-end encrypted communication. User6044478 • Oct 2017 • 5 agrees and 0 disagrees
- It's built atop Matrix, which provides distributed, federated instant messaging, voice and video calling with the ability to bridge into other networks (IRC, etc.) lampholder • Jul 2017 • 3 agrees and 0 disagrees
- Free and opensource with better performance and features for team communication. Guest • Aug 2017 • 3 agrees and 1 disagrees
- because its open source, decentralised, and end-to-end secure. Plus the folks at matrix.org are working to get us out of our communication silos by creating standards for communication interoperability! brinerustle • Mar 2018 • 1 agrees and 0 disagrees
- Federated, free standard and free software Guest • Feb 2018
Free Open Source Mac Windows Linux Web Android ... iPhone Android Tablet iPad Self-Hosted Chrome Safari F-Droid Firefox
Apps with End-to-End Encryption Decentralized Group chat Matrix.org protocol ... Video calling Voice Call Community based Custom widgets DRM Free Encrypted chat GitHub integration Group collaboration Integrated File Sharing MarkDown support File Sending Server Moderation Server side history Slack integration Team Collaboration Video calling Add a feature

200 Like
Mattermost

Mattermost is an open source, self-hosted Slack alternative. As an alternative to proprietary SaaS messaging, Mattermost brings...
- Its the same but you keep your server where you want so no one is playing with your data, and you can have an unlimited history depending on what you need for free so really way better ! Guest • May 2017 • 3 agrees and 1 disagrees
- It is very much a Slack clone with added features + it's open source! Guest • May 2017 • 2 agrees and 2 disagrees
- it is similar in features, and has some more, for example XMPP compatibility (-> many more client choice) and ability to self host it! Guest • Jul 2018
- 1. Open source; 2. most of the same functionality; 3. secure and private server possibilities (the data is, therefore, yours until the end of time); 4. extra features when it comes to customization, a big difference actually. Only negative is that Slack look a lot better design wise, so you can't customize it optimally. Guest • May 2017 • 0 agrees and 1 disagrees
- Mattermost is quite versatile and has been used within several of my past employers. Guest • May 2018 • 0 agrees and 1 disagrees
Freemium $ $ $ Open Source Mac Windows Linux Android iPhone ... Android Tablet iPad Self-Hosted JavaScript Go (Programming Language) Cloudron
Team Collaboration Data API Group chat Integrated File Sharing ... MarkDown support On-premises software Plugin API Slack integration Supports XMPP Add a feature

142 Like
Zulip

Zulip is a group chat app. Its most distinctive characteristic is that messages are threaded by topic, helping you have long-running, organized conversations....
- It's open source, and has really good threaded conversations. aviendha1591 • Nov 2017 • 4 agrees and 0 disagrees
- Three reasons: 1. Open source. 2. Stream 3. Topics abijith • Dec 2017 • 4 agrees and 0 disagrees
- Zulip offers a great unbeatable chatting experience. It shines in many places where Slack tends to slack. Sethu • Dec 2017 • 4 agrees and 0 disagrees
- Good community with great support. gamefreakerxD • Dec 2017
- Open-source, streams, topics, quick responses from devs hrishikeshpatil • Jan 2018
- Great community Easy Access Many organization sirepherox • Jan 2018
- It is open source and has a lot of topics. Guest • Jan 2018
- Zulip is very user friendly and is also open source! linacodes • Jan 2018
- It's open source and you can self host. It has great threading to group conversations so things are easier to find and more organized . Guest • Jul 2018
- One can easily switch in between conversation between different threads! Extremely helpful for any organisation. shantnukumar • Aug 2018
- Open Source without limitations when on premises. Much better information categorisation with Streams & Topics. Vibrant community. superbiche • Dec 2018
Free Open Source Mac Windows Linux Web Android ... iPhone Android Tablet BSD Self-Hosted
Threaded Conversations Group collaboration Chat Bot Community based ... GitHub integration Group chat Integrated File Sharing MarkDown support Team Collaboration Add a feature

134 Like
Matrix.org

Matrix is an open standard for decentralized persistent communication over IP. It can be used for decentralised group chat, WebRTC signaling, IoT-data transfer, ...
- Capable of everything Slack can do, but can be self-hosted - keeping a team's data in-house. nrg200 • Jul 2017
- It can be easily bridged to many other chat systems, including Slack, which makes transitioning *much* easier. It's also open source and decentralized (self-hostable + communication with other servers). Guest • Jul 2017
- Open source, fecentralized, federation, chat-voice-video function. User6044478 • Oct 2017
- Respects your Freedom. Increasingly popular Guest • Nov 2017
- Free open source instant messaging service with federation. Guest • Aug 2017 • 0 agrees and 1 disagrees
Free Open Source Mac Windows Linux Web Android ... iPhone Android Tablet iPad Self-Hosted WebRTC Python JavaScript Go (Programming Language) Java Perl
Apps with End-to-End Encryption Decentralized Chat Bot Distributed ... Encrypted chat GNU/linux-libre Group chat Real time collaboration Server side history Team Collaboration WebRTC Add a feature

104 Like
Rocket.Chat

Rocket.Chat is a Web Chat Server, developed in JavaScript, using the Meteor fullstack framework.
- Does everything Slack does AND it's open source. However, it's also self-hosted. This means you have to put in the effort to set it up, but you control your own data, which is a huge advantage to your privacy - your chats and files don't sit on someone else's servers, ready for them or hackers to look at. JohnFastman • Dec 2016 • 3 agrees and 1 disagrees
- Rocket.Chat comes very close to slack regarding it's core features and handling. Guest • Jun 2018 • 1 agrees and 0 disagrees
- open source, locally hosted so you own your data. Guest • Nov 2018 • 0 agrees and 1 disagrees
Free Open Source Mac Windows Linux Android iPhone ... Self-Hosted Cloudron
Group chat Ad-free Chat Bot Extensible by Plugins/Extensions ... Integrated File Sharing Location Mapping Share your screen Self-Serve Capability Slack integration Voice messages Add a feature

81 Like
HipChat

HipChat is an instant messaging service designed for companies and teams. It has persistent chat rooms, one-to-one chat, searchable chat history, file sharing via drag...
- Discontinued https://alternativeto.net/software/slack/ is acquiring Hipchat and https://alternativeto.net/software/stride-by-atlassian/ from Atlassian. the services will be discontinued after February 15th, 2019. https://www.atlassian.com/partnerships/slack
- Simple, very fast desktop client. Good web client. Guest • Feb 2018
Freemium Mac Windows Linux Web Android ... iPhone Android Tablet iPad Self-Hosted Apple Watch
Team Collaboration Integrated File Sharing Share your screen Add a feature

73 Like
TribeScale

TribeScale is a startup that aims to enhance teamwork in companies through the improvement of communication, coordination, and the pace on the basis of targets set.

Free Mac Windows Web Android iPhone ... iPad Self-Hosted
Goal setting Goal Tracking Group chat Group collaboration ... Real time collaboration Team Collaboration Team work Add a feature

24 Like
Let's Chat

Self-hosted chat for small teams. Features and Stuff BYOS (bring your own server) Persistent messages Multiple rooms New message alerts /...
- Discontinued As stated at https://github.com/sdelements/lets-chat/issues/781 , the project is no longer developed since August 2017. Last version, 0.4.0, released in June 2015, can be still downloaded from GitHub together with the source code.
Free Open Source Self-Hosted Cloudron
Team Collaboration Add a feature

36 Like
eXo Platform

eXo Platform is a Digital Collaboration Platform for enterprises. It helps people work together in a collaborative workplace.

Freemium $ $ $ Open Source Mac Windows Linux Web Android ... iPhone iPad Self-Hosted
App integration Group collaboration Real time collaboration Shared calendars ... Software as a Service Team Collaboration Team messaging Team work Add a feature

61 Like
Dialog Messenger

Dialog Messenger is a customized self-hosted platform usable across multi operation systems simultaneously. dialog provides SDK tools for client interface as well as for...

Free Personal Mac Windows Linux Web Android ... iPhone Self-Hosted
Encrypted chat Reactions Real time collaboration Team work ... Text chat Add a feature

24 Like
ZeroChat

An IRC-like internet chatroom hosted on ZeroNet, a distributed network. 0rc is a fully distributed website, and messages are shared through peers using the ZeroNet...

Free Open Source Mac Windows Linux Web Self-Hosted ... Python JavaScript ZeroNet
Decentralized Distributed Add a feature

10 Like
Hack Chat

hack.chat is a minimal, distraction-free chat application. Channels are created and joined by going to https://hack.chat/?your-channel . There are no channel lists, so a...

Free Open Source Web Android Self-Hosted
Distraction-free UI Add a feature

20 Like
Spectrum Chat

A newly open sourced self hosted Slack like alternative for building persistent chat communities.

Freemium $ $ $ Open Source Web Self-Hosted
Group chat Group collaboration Support for @mentions Real time collaboration ... Team Collaboration Team work Add a feature

6 Like
Kandan

Open Source private chat server. Your own private Chat server in minutes, plus additional features. No credit card required. A fast, secure and stable solution based on...

Free Open Source Web Self-Hosted Ruby on Rails
No features added Add a feature

9 Like
VideoMeeting

VideoMeeting is a free and open source video conference solution built to have video calls and chats using your web browser. It is a pure web application based on WebRTC...

Free Open Source Web Chrome OS Self-Hosted
Video calling Web-Based Add a feature

4 Like