Open-source alternatives to Weechat

A high-performance Internet Relay Chat (IRCv3) server for UNIX-like and Windows systems

Quassel IRC: Chat comfortably. Everywhere.

A web client for WeeChat

Official UnrealIRCd repository. Downloads are available from our site

Converse.js is an embeddable, self-hosted XMPP chat client that runs entirely in the browser. It communicates with XMPP servers using standard XML stanzas over WebSocket or BOSH transports, and provides end-to-end encryption through the OMEMO protocol with double ratchet algorithm and X3DH key exchange. The client is built on a plugin-based architecture that allows extending core functionality at runtime without modifying the client itself, and uses a DOM-based rendering approach with an event-driven message bus for internal coordination. The client manages message history through XEP-0313 Me

RobustIRC - an IRC network without netsplits, implemented in Go using the Raft consensus algorithm

Free, portable and lightweight Internet Relay Chat server

MongooseIM is Erlang Solutions' robust, scalable and efficient XMPP server, aimed at large installations. Specifically designed for enterprise purposes, it is fault-tolerant and can utilise the resources of multiple clustered machines.

Openfire is an XMPP communication server and enterprise messaging platform designed for real-time collaboration. It serves as a communication hub providing instant messaging, presence tracking, and multi-user chat capabilities for organizational use. The server supports federated network routing via an XMPP federation gateway, allowing users across different domains to exchange messages. It is designed for high availability through server node clustering and multi-node synchronization to balance client traffic and ensure continuous uptime. The platform integrates with external directory serv

Halloy is an IRCv3 chat client designed for real-time communication across multiple servers and networks. It implements modern protocol standards, including support for message tags, read markers, rich user metadata, and WebSocket connections. The project distinguishes itself through integrated anonymity and deep interface customization. It features native Tor and proxy routing to hide the user's connection origin and provides a themed environment with configurable window pane layouts, keyboard aliases, and custom color schemes. The client covers a broad range of capabilities, including chan

Candy — a JavaScript-based multi-user chat client

Desktop client for Cabal, the p2p/decentralized/local-first chat platform.

The official Asterisk Project repository.

Ricochet is an experimental kind of instant messaging that doesn't trust anyone with your identity, your contact list, or your communications.

A cross-platform app ecosystem, bringing iMessage to Android, PC (Windows, Linux, & even macOS), and Web!

sc-im is a text user interface spreadsheet calculator and data manager. It provides a keyboard-driven environment for performing mathematical computations and managing data grids within a command line interface. The application is scriptable, supporting custom functions, event-driven triggers, and the integration of external scripts to automate calculation tasks. It further allows for the loading of external compiled modules at runtime to extend its mathematical capabilities. The system covers data management through row sorting, filtering, and subtotal calculations. It supports data interop

A community discussion platform: Brings together the main features from StackOverflow, Slack, Discourse, Reddit, and Disqus blog comments.

Discourse is an open-source forum engine designed to facilitate long-form threaded conversations and community management. Built as a server-side application, it provides a structured, category-based interface for interactive online communities, supporting user authentication, moderation, and real-time content delivery. The platform utilizes a relational database to manage complex relationships between users, topics, and site settings. The application distinguishes itself through a modular architecture that allows for custom plugins and themes, enabling the adaptation of discussion spaces to

A chat app made by Flutter and Firebase. Support login with google account, chat with any user, send text, image and sticker, update avatar and profile. Demo: https://youtu.be/MOHE68LI5Eg Implement: https://medium.com/@duytq94/building-a-chat-app-with-flutter-and-firebase-from-scratch-9eaa7f41782e

Element Web is a web-based communication client used for real-time messaging and collaboration via the decentralized Matrix protocol. It functions as an end-to-end encrypted messenger, a VoIP client for voice and video conferencing, and an interface for interacting with integrated bots and external bridges. The project distinguishes itself through a modular architecture that supports runtime module loading and external script imports to extend core capabilities. It provides extensive white-labeling options, allowing for the customization of application branding, visual themes, and the use of

Circe is a Client for IRC in Emacs. It tries to have sane defaults, and integrates well with the rest of the editor, using standard Emacs key bindings and indicating activity in channels in the status bar so it stays out of your way unless you want to use it.

Do you have watched "Black Mirror" The first episode of the second season? The story of the “rebirth” to accompany the lover based on the text, photos, videos and other information posted on the Internet.

Berty is a peer-to-peer messaging application and framework designed for decentralized private messaging. It utilizes a distributed identity protocol and a decentralized database to enable end-to-end encrypted communication without relying on central servers, phone numbers, or email addresses. The project distinguishes itself through an offline messaging framework that uses Bluetooth Low Energy and multicast DNS for local device discovery. This allows peers to establish direct connections and exchange messages without internet or cellular data, using QR codes for secure contact exchange. The