Work in progress
To use mutt for your email client with the blinkenshell email server here is a minimal ~/.muttrc that will work. Consider this just a starting point,there are many other options you can set (see man mutt and man muttrc).
Note: Your triton ~/.forward must not exist, or not have a forwarding address in it. Otherwise emails sent to you will be forwarded rather than collected on the server.
Note: Mutt can't write files to /tmp on Triton, therefore you have to create your own ~/tmp directory and configure it in .muttrc:
# the tmpdir line probably will not be needed unless you are running mutt on triton set tmpdir = ~/tmp # imap: (to read emails) set spoolfile = 'imap://yourusername:email@example.com:143/INBOX' set folder = 'imap://mail.blinkenshell.org/INBOX' #smtp: (to send emails) set envelope_from_address = 'firstname.lastname@example.org' set use_envelope_from = yes # use the following line if you are running mutt on triton: set smtp_url = 'smtp://yourusername:email@example.com' # use this line if you are using mutt from another computer outside of the blinkenshell network: #set smtp_url = 'smtp://yourusername:firstname.lastname@example.org:587'