As regular readers know, I am a very happy user of mu/mu4e to handle my email. It lets me handle email completely from within Emacs and it happily lives side-by-side with Apple’s mail app so I can read and write mail with mu4e when I’m on one of my computers and use the Mail app when I’m on one of my iOS devices. It’s the best of both worlds.
Wojciech Siewierski tried mu4e but didn’t like it. He settled on Notmuch and notmuch.el. Like me he uses isync to retrieve his mail. He also uses msmpt to send it but I don’t bother with that. Siewierski started using Notmuch a year ago and just wrote a blog post about his experiences.
The TL;DR is that he likes it and has no plans to change. Notmuch is superficially similar to mu in that they both build and index a database of your emails. The clients, mu4e and notmuch.el are the mail user agents and run in Emacs. That means both systems offer you the advantages of reading, writing, and editing your emails from within Emacs.
The big difference, as far as I can tell, is that Notmuch likes to organize things around tags while mu simply offers a powerful search engine. At first I liked the idea of tags—I use them in virtually all my Org files—and wished mu had better support for them but then I realized that their use in Notmuch amounts to a proxy for mail folders. That’s the idea I was trying to get away from with mu. I simply throw all my read emails—at least the ones I want to keep—into a single folder and use mu’s powerful search capabilities to locate any that I need. Those search capabilities have yet to fail me in over two years of use.
Still, “different strokes for different folks” as the hippies used to say. Not everyone will like mu/mu4e and if you’re one of those people—like Siewierski—you can give Notmuch a try and see if it works better for you.