Never in a million years did I think I’d be using a command-line email client but Himalaya is actually really nice (I did set up some fish shell abbreviations for common commands, etc.) I’m particularly enjoying being able to compose messages in my regular editor (Helix Editor).
https://github.com/soywod/himalaya
I’m sure I’ll still be using Fastmail’s web interface too but this is nice to have alongside.
(This is one for the developers/tinkerers out there.)