nukosu@pao.moe

Mesh
Technitium Mesh is a secure, anonymous, peer-to-peer (p2p), open source instant messenger designed to provide end-to-end encryption. Primary aim of developing this instant messenger is to provide privacy which is achieved using cryptography and anonymity using Tor network. It can be used over Internet and private LAN networks (without Internet) for instant messaging and file transfer with support for private chats and group chats.

https://mesh.im/