apt install postfix
postconf -e 'home_mailbox=Maildir/'
postconf -e 'virtual_alias_maps=hash:/etc/postfix/virtual'

# In /etc/postfix/virtual
usuario@domin.io            usuario-real

postmap /etc/postfix/virtual
systemctl restart postfix
echo 'export MAIL=~/Maildir' >> /etc/bash.bashrc >> /etc/profile.d/mail.sh
source /etc/profile.d/mail.sh
cat | s-nail -s 'Test' -Snorecord usuario@domin.io