If history is going to repeat itself I should think we can expect the same thing again.

If you can't stand the heat in the dressing room, get out of the kitchen.

Defect-free software does not exist.

Lack of documentation is becoming a problem for acceptance.

Sure, but competition is good for the user.

Adding functionality is not just a matter of adding code.

As of today, the Postfix mail transport agent has almost 50,000 lines of code, comments not included.

For many people my software is something that you install and forget. I like to keep it that way.

Like all software, Qmail can survive only when it keeps up with changing requirements.

Most of the effort in the software business goes into the maintenance of code that already exists.

My reply is: the software has no known bugs, therefore it has not been updated.

One bug in an SMTP server can open up the whole machine for intrusion.

Postfix keeps running even if one Postfix process dies; Windows requires that someone restarts the service.

The challenge with Postfix, or with any piece of software, is to update software without introducing problems.

The Postfix security model is based on keeping software simple and stupid.

When I write software, I know that it will fail, either due to my own mistake, or due to some other cause.

Windows favors multi-threading, which means that a service is implemented by one single process.

Writing software that's safe even in the presence of bugs makes the challenge even more interesting.

At the time the Sendmail program had a very poor reputation with respect to security, with four root vulnerabilities per year for two successive years.

Coming back to the topic of computer security, the TCP Wrapper is an example of such a safety net. I wrote it when my systems were under attack by someone who appeared to walk through walls.