chasquid is an SMTP (email) server.

https://github.com/albertitohttps://github.com/albertito/chasquid/chasquid

It aims to be easy to configure and maintain for a small mail server, at the expense of flexibility and functionality.

It’s written in Go.

Features

• Easy to configure, hard to mis-configure in ways that are harmful or insecure (e.g. no open relay, clear-text authentication, etc.).
• Tracking of per-domain TLS support, prevents connection downgrading.
• SMTP UTF8 (international usernames).
• IDNA (international domain names).
• Hooks for easy integration with greylisting, anti-virus and anti-spam.
• Multiple domains, with per-domain user database and aliases.
• Multiple TLS certificates.
• Suffix dropping (user+something@domain -> user@domain).
• Easy integration with letsencrypt.
• SPF checking.
• Monitoring HTTP server, with exported variables and tracing to help debugging.