Self-Hosted Zulip Alternatives
Element is a secure collaboration and messaging app based on the Matrix protocol. It’s decentralised to deliver digital sovereignty, and based on an open standard for easy connections and interoperability. It is end-to-end encrypted by default.
- - Element is the most popular Self-Hosted alternative to Zulip.
Matrix defines a set of open APIs for decentralised communication, suitable for securely publishing, persisting and subscribing to data over a global open federation of servers with no single point of control.
Wire is the most secure collaboration platform featuring messenger, voice, video, conference calls, file-sharing, and external collaboration –all protected by the most secure end-to-end-encryption.
Mattermost is a secure, open source platform for communication, collaboration, and workflow orchestration across tools and teams.
Powered by WebRTC, Real-time video call, chat room and screen sharing entirely browser based.
Dirc is a peer-to-peer web application which uses WebRTC to set up connections between chat participants without requiring a back-end server. The static files can be self-hosted. Other features:
Fully open source instant messaging server and clients. No proprietary components or non-free dependencies. Backend in pure Go (GPL 3.0), with a command-line administration tool in python + gRPC. Clients for Android, iPhone, and Web - ReactJS (all licensed under Apache 2.0).
Kontalk is a secure instant messenger, allowing you to send and receive text, image and voice messages (other file types coming soon) to and from other Kontalk users completely free of charge.
Hack Chat Features
Self-hosted chat for small teams.
Let's Chat FeaturesDiscontinued
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.
Conduit is a simple, fast and reliable chat server powered by Matrix. Conduit is an alternative to Synapse and tries to be lightweight and easy to install, but it is still in development.