I’ve gotten fed up with Evolution‘s bugs and slowness. Even though I experience less problems than some weeks ago since I’ve applied a patch related to locks in e-d-s, Evolution has now become really too slow… and given that my mail flow is not really diminishing, I’ve come to the point when I think about migrating.
I’ve been a user of Gnus for years also (at home, with much satisfaction, as it runs fine inside a GNU Screen), so I could switch to it with moderate damage. Also, as I’m using org-mode, it would be quite complementary of course, staying more in Emacs 
One nice (and even priceless) feature of Evolution is the vfolders, that allow me to manage the tons of emails in different contexts, wherever that may be located. AFAIK, Gnus doesn’t offer any comparable feature. But it seems that the most interesting way to have it is to integrate Gnus with NotMuch. Fortunately, my colleague Roland has written a nice howto explaining (among other details of his mail system setup) how to integrate these together.
Now, if I’m able to setup a similar NotMuch + Gnus setup for newly received mail, I’m left with migrating all my piles of old mail, currently stored in Evolution.
It seems that one possible way to do so is through copying Evolution mail folders into a newly setup local IMAP server’s Maildir storage. The copy is supposed to preserve some flags like the read/unread status of the “important” flag.
From the first tests I’ve made, it’s possible to install a local Dovecot IMAPd server, configure it so that the mail is stored in the user’s ~/Maildir/ maildir directory, which can then be recognized by Evolution as a target for copying mail. It seems that nomuch can then be configured so that it doesn’t flag all new mails as unread, and understangs the imap server flags accordingly (unread, important, and such). Needless to say, I’m glad all these useful programs are packaged in Debian
I need to make further tests and also test Gnus + Notmuch integration, but having a possible solution to migrate my existing mail looks like a relief.
I’d be curious to read your alternative ideas for such a migration.
Stay tuned for next iterations.
