I considered myself an experienced sysadmin when, in 2007, a user of mine asked if I could make a trivial change to his mail configuration. It was nothing new to me. I had been running mail services for about ten years, hosting thousands of users over the course of time, and been contracted multiple times to setup mail infrastructures for others. I was familiar with Sendmail and Postfix, mail stuff was easy work that I could do while sipping a cup of coffee pondering about the meaning of life.
That user... I don't recall precisely his request, I'm still in denial, but it was of the kind that I would accept and deal with right away.
I started editing Sendmail's "configuration file" and I could not convince myself that what I had done was correct. The more I read the changes, the more they confused me. I had the intuition, a subconscious warning, that something was going to break for a weird reason. After a while, I decided to do what any sysadmin would do in that situation: take a leap of faith1.
I deployed, broke mail and reverted to previous configuration. I was devastated, ridiculed by the SMTP Daemon, my old trusted friend had slapped me in the face and I could see him laughing. At me, not with me.
To change my mind, I called a friend for a "beer and hacking session" at a pub nearby and wrote the first lines of a simple SMTP server. A few hours later, slightly intoxicated, I had the poolp.org SMTP server delivering its first mails to my mailbox and violating every single RFC requirement out there.
Years later and with the contribution of many people, OpenSMTPD has evolved a lot from the initial daemon I showed pyr@, chl@, henning@ and reyk@. It is dead simple, provides a wide range of features, has clean code and can be extended to achieve impressive setups.
I have no doubts someday it will rule the world.
-- Gilles Chehade
1 Don't do that.