You're reading the public-facing archive of the Category Theory Zulip server.
To join the server you need an invite. Anybody can get an invite by contacting Matteo Capucci at name dot surname at gmail dot com.
For all things related to this archive refer to the same person.
If you are attending the conference remotely, you might be in the position of wishing you could ask some questions to the speakers or some other folks who are here, informal or otherwise (perhaps questions which you wouldn't want to send via email, say) outside of the very brief question times. If you post them here (or dm me) I will do my best to pass them on, or perhaps they will be responded to directly here!
(Mostly I want to encourage more conference-related discussion, since Zulip hasn't been as lively as I hoped during this conference)