I have a mailbox containing tens of thousands of messages. It takes an hour or more to sync, which is just way too long, since I want to repeat this process every hour or so. I profiled it briefly and it seemed to be spending most of its time in c-client parsing imap messages. Other software in this domain has ways of doing less work, though I'd rather use mailsync if it could be fast enough, for a variety of reasons. I can imagine some simple approaches to incrementalism, but I wouldn't want to attempt any of them without guidance. It seems as though the mailing list has been closed down? How/where would this get discussed?