I've never been particularly happy with CLI or TUI email options. Aerc might just finally change that.
My TUI email journey has basically been: every couple of years, try and get a [neo]mutt setup I'm happy with, only to fall back to in-browser gmail after a few months at the most, when something in the rube-goldberg machine I've invariably constructed, breaks.
Some time in the late oughts I tried sup, a promising try built in ruby and which sported gmail-like threading by default. But it was slow, and never really did well with the HTML email that's just a constant of modern (and even late-oughts) life.
I've done the offlineimap dance, which became the isync dance, tried various lightweight/standalone SMTP senders like msmtp. These days the whole story is much better because of neomutt: it supports IMAP and SMTP directly, has grown native threading/tree-view support, and comes pre-baked with the half-dozen or so patches I used to always have to cobble together. But HTML email is still a pain, and gmail's crazy IMAP folders are still a pain, and the interface asking so much of the user at all times is still a pain.
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Aerc represents a much-needed fresh reboot, from a craftsman who clearly has a software worldview very similar to my own. It's highly extensible and powerful, but unlike long-in-the-tooth mutt, achieves this power under a self-imposed simplicity constraint. There are multiple configuration files, each one employing a simple INI-style format. There are keybindings, all of which are changable, and all of which are built out of commands in the program's ex-mode.
On top of the program itself, aerc ships with a directory of filter scripts, utilizing w3m to convert HTML email parts in the terminal, or using the system's native per-mimetype defaults to open them in an external program.
With these scripts and the structure of the program itself (modal, command-based, unix-oriented), and some really smart inventions like built-in folder name remapping, aerc satisfies the itch for a good old-timey UNIX program, while simultaneously anticipating the needs of an email client in the 2020s.
I'm loving it.
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