Startups

Screego - open source screen sharing for developers

SAMA - simple but advanced open source chat server for mobile and web apps.

Centralize real-time messaging, voice, video, AI, and apps for secure, reliable and unified communication among internal and external stakeh

Share sensitive information with self-destructing, encrypted links that are viewable only once.

ntfy is a simple HTTP-based pub-sub notification service.

Novu is the open-source notification and agent communication infrastructure.

Mumble is a free, open source, low latency, high quality voice chat application.

Live support chat for your website with Bot, Voice, Video, ScreenShare support.

Jami - the distributed and open source communication platform

a simple server for sending and receiving messages

GNU

GlobaLeaks is free, open source software enabling anyone to easily set up and maintain a secure whistleblowing platform.

Element is a Matrix-based end-to-end encrypted messenger and secure collaboration app.

A community-driven Matrix homeserver

Conduit is a simple, fast and reliable chat server powered by Matrix.

A peer-to-peer chat app that is serverless, decentralized, and ephemeral

Centrifugo is an open-source real-time messaging server — a self-hosted alternative to PubNub, Pusher, Ably, Socket.IO, Phoenix.PubSub & Sig

Open-source WebSocket server with built-in delivery guarantees, presence tracking, and message ordering.

Keeper.sh copies your events between Google Calendar, Outlook, iCloud and Fastmail so all of them show you as busy at the same times.