Discourse is a simple, flat forum, where replies flow down the page in a line. Replies are attached to the bottom and top of each post, so you can optionally expand the context of the conversation – without breaking your flow. | Zulip is powerful, open source team chat that combines the immediacy of real-time chat with the productivity benefits of threaded conversations. Zulip allows busy managers and others in meetings all day to participate in their teams chats. |
Remembers your place;Log in with … anything;Paste to share images;Search that actually works;Scalable moderation;Bring your friends;Your stuff belongs to you;Comprehensive API | Apps for every platform; Open source; Seamless integrations with everything you use |
Statistics | |
GitHub Stars 45.5K | GitHub Stars 23.7K |
GitHub Forks 8.7K | GitHub Forks 8.9K |
Stacks 276 | Stacks 223 |
Followers 246 | Followers 344 |
Votes 115 | Votes 366 |
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Integrations | |

Imagine all your team communication in one place, instantly searchable, available wherever you go. That’s Slack. All your messages. All your files. And everything from Twitter, Dropbox, Google Docs, Asana, Trello, GitHub and dozens of other services. All together.

HipChat is a hosted private chat service for your company or team. Invite colleagues to share ideas and files in persistent group chat rooms. Get your team off AIM, Google Talk, and Skype — HipChat was built for business.

Rocket.Chat is a Web Chat Server, developed in JavaScript, using the Meteor fullstack framework. It is a great solution for communities and companies wanting to privately host their own chat service or for developers looking forward to build and evolve their own chat platforms.

Mattermost is modern communication from behind your firewall.

Free chat rooms for your public repositories. A bit like IRC only smarter. Chats for private repositories as well as organisations.

Flowdock is a web-based team chat service that integrates with your tools to provide a window into your team's activities. With the team inbox, everyone on your team can stay up to date. Stay connected with Flowdock's iOS and Android apps.

See content and chat history anytime, including team chats with Skype that are visible to the whole team. Private group chats are available for smaller group conversations.

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Keybase is for anyone. Imagine a Slack for the whole world, except end-to-end encrypted across all your devices. Or a Team Dropbox where the server can't leak your files or be hacked.

Flarum is the next-generation forum software that makes online discussion fun. It's simple, fast, and free.