a free messaging app for Slack, Facebook Messenger, WhatsApp, Telegram and more.

• Franz @ GitHub.

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• 10 open-source Windows apps I can't live without - and they're all free @ ZDNet.

WhatsApp HTTP API (REST API) that you can configure in a click! 3 engines: WEBJS (browser based), NOWEB (websocket nodejs), GOWS (websocket go).

WhatsApp HTTP API (REST API) that you can install on your own server and run in less than 5 minutes!

• WAHA @ GitHub.

All your chats in one app. Yes, really.

• Beeper Bridge Manager @ GitHub.

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• docker-beeper - Beeper Desktop in your web browser! @ GitHub.

Delta Chat is a decentralized and secure messenger app.

💬 Reliable instant messaging with multi-profile and multi-device support.

• Delta Chat @ GitHub.

Batteries included UI to monitor your Messenger workers, transports, schedules, and messages.

fast & lightweight self-hosted messenger. A federated messenger for self-hosting.

An elegant Facebook Messenger desktop app.

Caprine @ GitHub

An open network for secure, decentralized communication. Matrix is an open source project that publishes the Matrix open standard for secure, decentralised, real-time communication, and its Apache licensed reference implementations.

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• Giving Up on Element & Matrix.org @ マリウス.
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• Building a serverless, post-quantum Matrix homeserver @ Cloudflare.
• Use Protocols, Not Services @ ~~p.
• Episode 146 @ Linux Dev Time.

he most secure messenger in the world.

Whatsapp like messenger with encryption. Has a GNU/Linux command line client.