notqmail is the collaborative Open Source successor to qmail and netqmail. It begins with stable, compatible, small releases to which existing qmail users can safely update, and aims to become a more extensible, more easily packaged, and more modern Mail Transport Agent suitable for most needs.

qmail's design principles haven't always prevented bugs or holes, nor have they always made adding new functionality easy. But pretty often we get both. And that's why we continue to invest in this codebase.

It's not qmail. It's also not netqmail.

We all use email, so we all use email servers. notqmail is software for running an email server. Someday, if we do a good job, some of the many articles about how and why to run your own will recommend notqmail.

notqmail is a community-driven fork of qmail, beginning where netqmail left off: providing stable, compatible, small releases to which existing qmail users can safely update. notqmail also aims higher: developing an extensible, easily packaged, and increasingly useful modern mail server.
https://github.com/notqmail/notqmail/wiki