@teleclimber If you don't mind maintaining your local index (and fair enough if you do mind), then I would imagine any of the Xapian based solutions like notmuch or mu would match GMail in terms of retrieval time. The other stuff about effective searching is much harder to quantify, but e.g. support for phrase search is also similar.
Disclaimer: I maintain and use notmuch, and barely use GMail.
@bremner thanks for putting me on the right track. Looks like dovecot has FTS plugins, including one based on Xapian. That might work for me. Not much of a check-my-mail-in-emacs kind of guy. 😁
@teleclimber IMAP is definitely good for choice of client. You might also look at astroid which is gtk and neomutt, which is curses, both notmuch backed
A Mastodon instance for maths people. The kind of people who make \(\pi z^2 \times a\) jokes.
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