Best open-source alternatives to Discord

Rocket.Chat is an open-source communications platform aimed at organizations that need secure, customizable collaboration tools. It supports team messaging and real-time conversations for internal coworkers as well as external communication with customers, citizens, or partner companies. The project is designed for self-hosted, cloud, and air-gapped deployments, making it suitable for regulated or high-security environments. It also includes security and governance features such as identity management, end-to-end encryption, and role- and attribute-based access control, while offering extensibility through a marketplace, Apps-Engine, and external integrations.

Discourse is an open-source community platform designed for people who want to host their own discussion spaces with full control over infrastructure and configuration. It is positioned as a forum and community hub, with official hosted service available for teams that prefer not to manage servers themselves. The platform supports core community features such as discussion topics, real-time chat, themes, and plugins, making it suitable for public forums, support communities, and other collaborative spaces. The README also highlights a long-running ecosystem, documentation for development and setup, and a RESTful Rails-backed API, indicating a mature web application built for extensibility and self-hosting.

Zulip is an open-source team chat platform designed to help organizations manage both real-time and asynchronous communication in a more structured way than traditional chat apps. Its signature feature is topic-based threading, which keeps conversations organized and makes it easier for distributed teams to follow multiple discussions without losing context. The project is aimed at teams, open-source communities, and other organizations that need productive group communication. The README highlights self-hosting on Ubuntu or Debian Linux, deployment via Docker, and hosted cloud options through Zulip Cloud. It also emphasizes a large contributor community and extensive documentation for both code and non-code contributions, suggesting a mature project with a broad user and developer ecosystem.

The Lounge is a self-hosted web IRC client intended for people who want a persistent, browser-based way to stay connected to IRC networks. It is positioned as a modern alternative to traditional IRC clients, with features such as push notifications, link previews, and message markers to make IRC feel more contemporary. It is aimed at users who want their IRC presence to persist across devices and sessions. The README emphasizes that it stays connected while the user is offline, works across platforms wherever Node.js runs, and provides a responsive interface for desktop, smartphone, and tablet use. The project also documents a source-based installation path for development and links to a Docker-based deployment option for stable releases.

Mumble is an open source voice-chat system built on Qt and Opus. It is aimed at users who need real-time, low-latency communication, and it is split into a desktop client and a separate server component. The client is available on Windows, Linux, FreeBSD, OpenBSD, and macOS, while the server can run wherever Qt is available. The project appears to serve both individual users and communities that want to host their own voice infrastructure. The README points to build instructions, server configuration documentation, and plugin documentation, suggesting it is suitable for self-hosted deployments and for extending functionality through plugins. It also includes an OpenGL overlay feature for games and references packaged, Docker-based, and source-build installation paths.

Mattermost is an open core collaboration platform designed for teams that want to self-host their communication and workflow stack. It provides a web-based interface and native clients for desktop and mobile, and is positioned for use cases such as DevSecOps, incident resolution, and IT service desk operations. The project is the primary source for core platform development and is implemented in Go and React. The software runs as a single Linux binary and depends on PostgreSQL for storage. The README emphasizes deployment flexibility, with installation paths for Docker, Ubuntu, tar archives, Kubernetes, and Helm. It also points users to product and developer documentation, and highlights a broad integration surface including webhooks, slash commands, drivers, web services, apps, and plugins.

Campfire is a web-based chat application intended for self-hosting. It is presented as a collaborative messaging tool for teams or groups that need rooms, direct messaging, file sharing, and searchable conversation history in one place. The README emphasizes that it can be deployed as a single-machine instance with all required components bundled together. The project appears designed for operators who want a relatively turnkey self-hosted chat system. Deployment is supported through ONCE, which can guide setup and keep the instance updated automatically, or by running the Docker image directly. The README also notes an admin-account setup wizard on first launch and an API intended for bot integrations, suggesting it can fit into automated workflows as well as human chat use.

Tailchat is an open source instant messaging and collaboration platform positioned as a “noIM” application: it aims to go beyond chat and act as a customizable workspace for individuals, teams, and enterprises. The project emphasizes privacy, invited-only groups, and a structure that lets users organize discussions into panels and spaces rather than relying on a traditional flat chat model. It is built with a front-end microkernel and a backend microservice architecture, and its plugin system is meant to let developers extend the product and integrate third-party applications in a native-feeling way. The README presents Tailchat as suitable for scalable deployments and secondary development, with official documentation, a nightly online demo, and deploy options referenced for container-based hosting.

InspIRCd is an Internet Relay Chat server aimed at users who need a self-hosted, high-performance IRCv3 service. It supports UNIX-like systems and Windows, and the README emphasizes that the project is actively developed, with the master branch considered unstable for production use. The project is built from source on most UNIX-like platforms, with documentation provided for source installation on both UNIX-like systems and Windows. It also offers binary packages for some operating systems and a Docker image. Additional modules can be enabled during builds, and the project provides official documentation, support resources, and a test network for experimentation.

Tuwunel is a Matrix homeserver implementation aimed at organizations and self-hosters that need a scalable alternative to Synapse. It is written entirely in Rust and is described as low-cost, enterprise-ready, and community-driven while implementing the Matrix specification for almost all use cases. The project positions itself as the official successor to conduwuit. The README emphasizes practical deployment paths rather than a hosted service. Users can install it via source, static binaries, Debian/RPM packages, Arch, Nix, Alpine, or Docker, then configure a server name and database path before starting the server. It can run with or without a reverse proxy, though Caddy is recommended for automated TLS. The first user to register becomes server admin, and the project provides migration guidance for existing conduwuit deployments.

Element is a Matrix client aimed at people who want to access Matrix chats through either a web browser or a desktop application. The README positions it as the main Element Web project in a larger monorepo, with related components and documentation links for installation, configuration, development, and translation. It can be used immediately through the hosted service at app.element.io, or self-hosted by following the installation documentation. The project also supports a desktop experience through an Electron wrapper, with pre-built downloads available from Element’s site or a path to build it from source. The README emphasizes browser compatibility, community triage, and a commercial licensing option alongside open-source licensing.

RetroShare is a decentralized communication toolkit aimed at users who want private and secure messaging and collaboration without relying on a central service. It is presented as a cross-platform project and includes capabilities for file sharing, chat, messages, forums, channels, and boards, suggesting it is intended for peer-to-peer social and collaboration use. The README focuses on source checkout and compilation rather than end-user installation, and it points contributors to platform-specific build guides for Windows, macOS, and Linux. It also references packaged builds and a separate documentation site, indicating that the project is maintained with multiple supported environments in mind and is likely used by technically inclined self-hosters and desktop users.

Chatto is a self-hostable chat application aimed at teams and communities. The repository packages several components together: the main chat server, a CLI, a bundled web frontend, an identity provider, and supporting framework modules. The README positions it as easy to run locally and suitable for development or self-hosted deployments, with cloud hosting planned for later. The project also includes adjacent tooling for workflows and identity, showing that it is more than a simple chat UI. Development is driven through the `mise` tool, which installs dependencies and starts the application stack, and a fuller development mode can bring up supporting services like Authling, Runling, Mailpit, and LiveKit. The README also documents a default development login, indicating a multi-user product with authentication. The codebase uses a mixed licensing model, with the core Chatto software under AGPL and some modules under Apache-2.0 or MIT.

SAMA is a chat server and messaging protocol project intended to serve as an alternative to XMPP. It is aimed at developers building messaging products and at users of the associated client applications, including a web frontend and a Flutter mobile client. The repository describes the server as part of a broader SAMA stack powered by uWebSockets.js, with infrastructure centered on Node.js, MongoDB, Redis, and AWS. Deployment and development guidance points to Docker-based setup documentation, and the README highlights a public cloud demo that can be used to try the full stack. The project also exposes documented APIs for common messaging functions such as users, conversations, messages, activities, address book, and push notifications.

UnrealIRCd is an open source IRC server intended for running public or private IRC networks. It has been maintained since 1999 and is positioned as a mature, widely deployed daemon with a strong emphasis on modularity, security, and deep configuration control. The project is aimed at administrators who need a feature-rich IRC server rather than a lightweight chat client. Its README highlights support for modern IRC capabilities such as IRCv3, TLS, cloaking, JSON-RPC, anti-flood and anti-spam protections, GeoIP, and remote includes. Installation is documented for source builds on Unix-like systems and for Windows, and the project maintains extensive online documentation, FAQs, and support channels for operators.

Synapse is a Matrix homeserver implementation developed and maintained by Element. It is intended for people and organizations that want to run their own Matrix server for secure, interoperable real-time communication, either from source or as part of Element’s deployment offerings. The README emphasizes that Synapse can be deployed standalone, with documentation covering installation, configuration, federation, reverse proxy setups, and upgrades. It is also shipped as part of Element Server Suite, which provides official deployment paths and commercial support options. The project is open source under AGPL, with an additional commercial license available from Element for organizations that need that arrangement.

ngIRCd is a lightweight IRC daemon intended for small or private networks. It is written in C, distributed under the GNU GPL, and aims to provide a simple, portable server that is easy to configure and maintain. The project supports both standalone operation and participation in a larger IRC network, including deployments across a LAN or the internet. It is aimed at administrators who need a straightforward IRC service with common protocol features such as IPv6, SSL/TLS, PAM-based authentication, user cloaking, and compatibility with a broad range of platforms.

Chitchatter is a browser-based communication app aimed at people who want private, secure conversations without relying on a central backend. It is designed around peer-to-peer networking, so users can connect directly in rooms and share a room URL for private chats. The project emphasizes decentralization, ephemeral messaging, and end-to-end encryption, with message content never persisted to disk. The project is suitable for groups, friends, families, and anyone needing quick private coordination, screen sharing, or secure file transfer. It also supports embedding into other web apps through a web component. A self-hosting path is mentioned, and an optional API server can be used for enhanced connectivity, but the core experience works without one.

Databag is a self-hosted federated messenger built for lightweight deployment and decentralized communication. It is aimed at users who want to run their own messaging node while still allowing accounts on different nodes to communicate with each other. The project emphasizes privacy and efficiency: it uses public-private key identity, end-to-end encryption, topic-based threads, and websocket-based push events. It also supports audio and video calling through a separate STUN/TURN relay, mobile notifications, and multi-factor authentication. The README highlights broad deployment options, including Docker Compose, manual installation on constrained hardware, and integration with various self-hosting platforms.

ClickClack is a self-hostable chat system designed for teams that want one platform for people, bots, and agents. It bundles a Go backend, a Svelte web frontend, a CLI, and a TypeScript SDK behind an API-first architecture, making it suitable for both interactive chat use and programmatic integrations. The project is aimed at self-hosters and developers who need a chat service they can deploy themselves, extend, and automate. The README highlights web and desktop clients for day-to-day use, plus REST and WebSocket access for external clients, bots, and custom tooling. Deployment options include release binaries, Docker, and source builds, with documentation covering authentication, storage, backups, and production configuration.

Quassel IRC is a cross-platform IRC client designed around a distributed architecture. Instead of running as a traditional single-process chat app, it uses a central core that one or more clients can connect to and disconnect from, allowing users to stay connected to IRC sessions while switching devices or interfaces. The project is intended for users who want a comfortable graphical IRC experience on major platforms, while also benefiting from a persistent core-side connection model. The README points users to official downloads, nightly builds, and the project wiki for setup and deeper documentation. It also notes that the core can create its database and initial admin user on first run, and that additional users and password changes are managed through the core command-line tool.

Tigase XMPP Server is a Java-based XMPP/Jabber server designed for deployments that need a modular, standards-compliant messaging backend. It targets administrators and organizations that want to run their own XMPP infrastructure with support for client, server-to-server, and component connections. The project emphasizes protocol coverage and extensibility. The README highlights support for XMPP over TCP, BOSH, and WebSockets, plus features such as service discovery, multi-user chat, publish-subscribe, message archiving, stream management, and push notifications. It also includes an HTTP API for integrating with systems that do not speak XMPP directly. The repository provides source code for the core server, while related Tigase projects add optional components, tools, clients, and IoT integrations.

A simple, fast, and reliable chat server powered by Matrix.

A project with documentation available at robustirc.net/docs.