Software

A simple, fast, and reliable chat server powered by Matrix. ([Source Code](https://gitlab.com/famedly/conduit))

Fully-featured Matrix client for Web, iOS & Android. ([Source Code](https://github.com/element-hq/element-web))

Whistleblowing software enabling anyone to easily set up and maintain a secure reporting platform. ([Demo](https://demo.globaleaks.org), [Source Code](https://github.com/globaleaks/globaleaks-whistleblowing-software))

Software framework for decentralized, peer-to-peer networking. ([Source Code](https://gnunet.org/git/))

Notification server with Android and CLI clients (alternative to PushBullet). ([Source Code](https://github.com/gotify/server), [Clients](https://github.com/gotify/android))

Anonymously share files, browse and publish _freesites_ (web sites accessible only through Hyphanet) and chat on forums. ([Source Code](https://github.com/hyphanet/fred))

Universal communication platform which preserves the user's privacy and freedoms. ([Source Code](https://git.jami.net/savoirfairelinux?sort=latest_activity_desc&filter=jami))

Live Support chat for your website. ([Source Code](https://github.com/LiveHelperChat/livehelperchat))

Low-latency, high quality voice/text chat software. ([Source Code](https://github.com/mumble-voip/mumble), [Clients](https://wiki.mumble.info/wiki/3rd_Party_Applications))

Notification infrastructure for developers. ([Source Code](https://github.com/novuhq/novu/))

Push notifications to phone or desktop using HTTP PUT/POST, with Android app, CLI and web app, similar to Pushover and Gotify. ([Demo](https://ntfy.sh/app), [Source Code](https://github.com/binwiederhier/ntfy), [Clients](https://github.com/binwiederhier/ntfy-android))

Share sensitive information securely with self-destructing links that are only viewable once. ([Demo](https://onetimesecret.com), [Source Code](https://github.com/onetimesecret/onetimesecret))

One-Time-Secret sharing platform with a symmetric 256bit AES encryption in the browser. ([Source Code](https://github.com/Luzifer/ots))

Secured and decentralized communication system. Offers decentralized chat, forums, messaging, file transfer. ([Source Code](https://github.com/RetroShare/RetroShare))

Communications platform that puts data protection first (alternative to Gitter.im and Slack). ([Source Code](https://github.com/RocketChat/Rocket.Chat))

Next-Gen self-hosted chat server and clients. ([Demo](https://app.samacloud.io/demo), [Source Code](https://github.com/SAMA-Communications/sama-server), [Clients](https://github.com/SAMA-Communications/sama-client))

Screego is a simple tool to quickly share your screen to one or multiple people via web browser. ([Demo](https://app.screego.net/), [Source Code](https://github.com/screego/server))

Spectrum 2 is an open source instant messaging transport. It allows users to chat together even when they are using different IM networks. ([Source Code](https://github.com/SpectrumIM/spectrum2))

Stoat is a user-first chat platform built with modern web technologies. ([Source Code](https://github.com/stoatchat/self-hosted))

Server for [Matrix](https://matrix.org/), an open standard for decentralized persistent communication. ([Source Code](https://github.com/element-hq/synapse))

Next generation noIM application in your own workspace, not only another Slack/Discord/rocket.chat. ([Demo](https://nightly.paw.msgbyte.com/), [Source Code](https://github.com/msgbyte/tailchat))

All-in-one customer engagement platform from lead-gen to post-sales, from WhatsApp to your website. With omni-channel live agents and AI-powered chatbots (alternative to Intercom, Zendesk, Tawk.to and Tidio). ([Source Code](https://github.com/Tiledesk/tiledesk))

Instant messaging platform. Backend in Go. Clients: Swift iOS, Java Android, JS webapp, scriptable command line; chatbots. ([Demo](https://sandbox.tinode.co/), [Source Code](https://github.com/tinode/chat), [Clients](https://github.com/tinode/webapp))

Distributed, secure messenger with audio and video chat capabilities. ([Source Code](https://github.com/TokTok/c-toxcore))