Our email hosting stack uses a suite of open source tools:
Postfix is a popular mail transfer agent - it’s easy to use, flexible and includes support for Sendmail’s mail filters. We use Postfix.admin which provides an web based interface to configure and manage a Postfix based email server.
Postfix.admin is an open source web based interface to configure and manage a Postfix based email server
Roundcube is an IMAP web-based email client, providing MIME support, address book, folder manipulation, message searching and spell checking.
Dovecot is a secure IMAP and POP3 email server. It plays well with Postfix and is extensible through the use of plugins.
AMaViS is a content filter for email that implements mail message transfer, decoding, does some processing and checking, and interfaces with external content filters to provide protection against spam, viruses and other malware.
ClamAV is antivirus software for detecting trojans, viruses, malware & other malicious threats.