Engineering blog
A secret-sharing protocol that works when the other person isn't there
How Secret Share moves a secret browser-to-browser when it can, and parks it as an encrypted dead drop when it can't: the one-code-two-jobs split, why park-first beats pure P2P and pure dead-drop, key confirmation that makes the signaling server MITM-proof, and why read-once forced Durable Objects over KV.