github.com/katzenpost/doubleratchet (go): Package ratchet originally written by AGL to implement the axolotl ratchet (designed by Trevor Perrin) for the Pond messaging system but then modified for a Katzenpost decryption mix network messaging system. Improvements herein made by Masala, Sofia Celli and David Stainton. David's latest changes turn the ratchet into a computationally expensive PQ hybrid ratchet wherein there's an ECDH and a CSIDH ratchet which both progress together. Both of these ratchets feed their computed shared secrets into the KDF ratchet via the root KDF chain. More clever designs and feedback encouraged.
Keywords: hacktoberfest