Free, open-source Windows chat where you watch every keystroke appear live — end-to-end encrypted, no accounts, nothing stored. Share a 6-char code to connect. Both sides get fresh ECDH P-256 keys each session. Messages are AES-256-GCM locked before leaving your machine. Includes file transfer, shared whiteboard, Walk Web (push URLs), themes, and profiles. Requires the SemaBuzz-Relay — single binary, ~10 MB, MIT licensed.