Prototype, mailbox-only for now — no live WebRTC layer yet (see
D008 in this repo's own plan).
Messages are written to cinder under keys derived from your shared
secret and picked up by polling — works even if the other person
isn't online right now. Whoever knows this secret can read and
write to this conversation — treat it like a password, not a
nickname.
Same secret on both sides opens the same conversation. A weak secret here is worse than for a one-off file transfer — anyone who learns it can read the whole history (within cinder's 7-day window per message) and inject fake messages, with no time limit at all.
Or pair automatically
Each side generates a one-time key and you both derive the same
secret between you (ECDH) — nobody but the two of you ever
transmits it, and it's never reused for another conversation.
Recommended over typing a secret by hand.