Hosting my own for more than 10 years. Using a hosting provider's box. Postfix, dovecot, roundcube stack, and letsencrypt certs. Postfix is pretty solid. Instal

Hosting my own for more than 10 years. Using a hosting provider's box. Postfix, dovecot, roundcube stack, and letsencrypt certs. Postfix is pretty solid. Install and forget. First thing I do when moving to a new server is check whether the new box's IP is black listed in any mail-blacklist-dns service. If not, it's good. What I have also found is that Gmail and other services are relatively forgiving on your server's IP, but marks mail as spam based on context and content.