Four modern mail systems for self-hosting
We have previously published detailed hands-on guides to the configuration of modern mail security standards for Postfix [DANE, SPF/DKIM/DMARC] and Exim [DANE, SPF/DKIM/DMARC]. From reader feedback, we’re aware that the guides are often used as ‘instruction manuals’ for the step-by-step creation of full-featured, secure and scalable mail systems. However, it’s also apparent from the guides that setting up all the various security mechanisms is a considerable undertaking, which requires a reasonable amount of technical know-how.
It goes on to discuss Mox (“the most comprehensive support for the security standards. The software is also very easy to install and configure)”), Chasquid (“Chasquid offers only a lightweight Message Transfer Agent (MTA) as an alternative to Postfix and Exim”), Stalwart (“The Stalwart Mail Server is in principle a commercial product designed for scalability and security. However, the developers also provide a Community edition in open-source form. The Community edition lacks the enterprise functionality, including AI, SAML authentication, monitoring, clustering, multi-tenancy, branding, undelete and support. Nevertheless, protection against spam, phishing and other malware is included in all editions.”) and Maddy (“Maddy sits somewhere between Chasquid and Mox. The software is (also) written in Go and made up of functional modules, which are linked together during configuration to form an MTA. Support for SPF, DKIM, DMARC, DANE and MTA-STS is built in. Maddy has its own IMAP implementation, but it’s still under development. For business use, the advice is to combine Maddy with Dovecot for the time being (as with Chasquid). Use of Unbound as a validating resolver (as with Mox) is also recommended. The developers say that the software should currently be regarded as a beta product.”)