Add Maddy Mail Server

README.md

@@ -315,6 +315,7 @@ _Simple deployment of a mail server, e.g. for inexperienced or impatient admins.
 - [Inboxen](https://inboxen.org) - Inboxen is a service that provides you with an infinite number of unique inboxes. ([Source Code](https://github.com/Inboxen/Inboxen)) `GPL-3.0` `Python`
 - [homebox](https://github.com/progmaticltd/homebox) - Suite of Ansible scripts to deploy a fully functional mail server on Debian. Unobtrusive and automatic as much as possible, focusing on stability and security. `GPL-3.0` `Shell`
 - [iRedMail](http://www.iredmail.org/) - Full-featured mail server solution based on Postfix and Dovecot. ([Source Code](https://github.com/iredmail/iRedMail)) `GPL-3.0` `Shell`
+- [Maddy Mail Server](https://github.com/foxcpp/maddy) - All-in-one mail server that implements SMTP (both MTA and MX) and IMAP. Replaces Postfix, Dovecot, OpenDKIM, OpenSPF, OpenDMARC with single daemon. `GPL-3.0` `Go`
 - [Mailcow](https://mailcow.email/) - Mail server suite based on Dovecot, Postfix and other open source software, that provides a modern Web UI for administration. ([Source Code](https://github.com/mailcow/mailcow-dockerized)) `GPL-2.0` `Docker/PHP`
 - [Mailu](https://mailu.io/) - Mailu is a simple yet full-featured mail server as a set of Docker images. ([Demo](https://github.com/Mailu/Mailu/wiki/Demo-server), [Source Code](https://github.com/Mailu/Mailu)) `MIT` `Docker/Python`
 - [Mail-in-a-Box](https://mailinabox.email/) - Turns any Ubuntu server into a fully functional mail server with one command. ([Source Code](https://github.com/mail-in-a-box/mailinabox)) `CC0-1.0` `Shell`