IETF124 has an open to all hackathon on Saturday and Sunday
The ATProto community will be in town and attending on Sunday (this event). More info in the ATProto Community Forum https://discourse.atprotocol.community/t/update-on-timing-and-plan-for-montreal/164
Relevant links:
* IETF124 Hackathon https://www.ietf.org/meeting/hackathons/124-hackathon/
* Hackathon Wiki https://wiki.ietf.org/en/meeting/124/hackathon