Software

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))

Conversational app builder (alternative to Typeform and Landbot). ([Source Code](https://github.com/baptisteArno/typebot.io))

Zulip is a powerful, open source group chat application. ([Source Code](https://github.com/zulip/zulip))

Email forwarding service for creating aliases. ([Source Code](https://github.com/anonaddy/anonaddy))

Complete email solution that runs on any webspace with PHP and MariaDB. It supports POP3 catchall mailboxes and can also integrate with Postfix or b1gMailServer if you're running your own server. ([Source Code](https://codeberg.org/b1gMail/b1gMail), [Clients](https://www.b1gmail.eu/en/start/addon-b1gmailserver/))

Your Debian-based data center in a box. A set of general-purpose Ansible roles that can be used to manage Debian or Ubuntu hosts. ([Source Code](https://github.com/debops/debops))