Reference
FAQ
Short answers to common questions.
Does it store my email?
Only headers (sender, subject, date, size, flags and list headers) in a local SQLite index. Message bodies stay on your mail server; previews fetch one body on demand and do not keep it.
Does opening mailsieve mark my mail as read?
No. Headers are fetched with BODY.PEEK, which never changes the read state.
Will it work with Gmail labels?
Yes. mailsieve indexes All Mail with its labels, so in: matches labels and archive removes the Inbox label the way Gmail does.
How fast is it?
Against a local Dovecot server, a first sync of 20,000 messages takes under a second and queries answer in milliseconds. Real providers are limited by the network, so expect longer first syncs.