Comment by WhyNotHugo

I’ve recently written ImapGoose, a daemon which keeps a remote IMAP mailbox in sync with a local tree of Maildir: https://whynothugo.nl/tags/imapgoose/

It relies on “modern” (2009) extensions to minimise traffic and avoids polling entirely (relying on the server to notify of new messages or changes as they happen).

It’s currently quite stable. The only known issue is that it can take a while to detect a timeout when the system is suspended and woken up again (there’s no portable API to detect suspend/resume).

Since then, I’ve been working on a simple TUI email client based on notmuch and maildir. So far it works really well for processing email, but lacks any capabilities for handling attachments, composing, sending (these are obviously on the roadmap).