I'm in the process of setting up my own e-mail infrastructure. I have maildir, certificates, IMAP, SASL, TLS, and antivirus working, with anti SPAM and the web

I'm in the process of setting up my own e-mail infrastructure. I have maildir, certificates, IMAP, SASL, TLS, and antivirus working, with anti SPAM and the web GUI left to do. I built and configured the MTA and the IMAP server to use a SQL database to do their table lookups. On a platform where I had to architect, compile, link, and package everything myself, because I didn't want Sendmail so I ripped it out and then had to seamlessly integrate the MTA of my choice with the OS. (I used to admin Sendmail for a living back in the day when SASL and TLS were science fiction.) It's a nightmare. I postponed this for 15 years knowing how bad it will be. It's far worse than that. During the last two years while I've been trying to figure it all out, I seriously thought about ditching e-mail altogether. The last year was spent reading various documentation. The DNS MX records aren't even in yet, and I already see port scans and hack attempts on port 25, probing for security flaws and configuration errors, already trying to exploit my MTA infrastructure. And before I go live, I have to recompile OpenSSL, SASL, antivirus and the MTA at the minimum, to get all the security fixes rolled in. I'm not even done yet, and the antivirus engine is already complaining that it's outdated. It's a nightmare.