Add “Build Your Own Mail Server” to Build-Your-Own-X Series

[nishchayjeet]

I'm a big fan of your Build-Your-Own-X series—it's been an incredible way to learn by building real systems from the ground up. I wanted to suggest an addition that I think could be both challenging and educational: Build Your Own Mail Server.

A mail server encompasses multiple protocols (SMTP, IMAP, POP3), security layers (TLS, SPF, DKIM, etc.), and queuing systems—making it a great project to teach core networking, systems programming, and internet standards. It's also a practical tool with real-world relevance, and one that developers often take for granted in daily use.

It would be amazing to break this down into stages (e.g., basic SMTP server, handling inbound messages, queuing and relaying, adding IMAP support, etc.), much like you’ve done with other projects.

Thanks for building such an awesome platform and for considering the idea!