The blog post provides a detailed step-by-step guide for setting up a mail server on OpenBSD, using Opensmtpd, Dovecot, DKIM, and Spamd. The author shares their stack and configuration files, highlighting the secure and stable nature of OpenBSD for hosting email. Unique information includes utilizing acme-client for TLS certificates and tweaking base Dovecot configuration to avoid file limit issues. The post also includes setting up DKIMProxy to sign outgoing emails and mentions the option of using Spamd for spam filtering. Overall, a comprehensive guide for self-hosting email on OpenBSD.
https://nicolascarpi.github.io/openbsd/2019/04/03/openbsd-mail-server.html