# Double Ratchet Projects at AI Tinkerers

> Canonical HTML: https://aitinkerers.org/technologies/double-ratchet
> Markdown URL: https://aitinkerers.org/technologies/double-ratchet.md
> Technology record last updated: 2026-03-03T14:49:36Z
> Generated: 2026-09-21T01:41:54Z

A cryptographic key management algorithm that provides end-to-end encryption with automatic, per-message re-keying for forward secrecy and post-compromise security.

The Double Ratchet algorithm, developed by Trevor Perrin and Moxie Marlinspike in 2013, is the backbone of the Signal Protocol and secures communications for over 2 billion users on platforms like WhatsApp and Facebook Messenger. It functions by nesting two distinct cryptographic processes: a symmetric-key ratchet based on a Key Derivation Function (KDF) and an asymmetric ratchet utilizing Diffie-Hellman (DH) exchanges. This dual-layered approach ensures that every message uses a unique, short-lived session key. If an attacker compromises a specific key, they cannot calculate previous keys (forward secrecy) or predict future ones (post-compromise security), as the DH ratchet constantly injects new entropy into the system to 'heal' the connection.

- Official technology site: https://signal.org/docs/specifications/doubleratchet/
- Public AI Tinkerers demos and talks: 1
- Result page: 1 of 1

## Recent Public Talks and Demos

### [Combining end-to-end encryption with multiple AI models in Doctor Dok](https://poland.aitinkerers.org/talks/rsvp_HlA0hR8KwbQ)

Creator of Doctor Dok, ex-CTO & Co-Founder Catch The Tornado

- Event context: AI Tinkerers Poland - First Inaugural Meetup in Warsaw (November) — 2024-11-21 — Poland
- Public talk page: https://poland.aitinkerers.org/talks/rsvp_HlA0hR8KwbQ

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