I’m the founder/developer behind MailerMine, an email infrastructure product. I’m sharing this for the engineering discussion, not as a promotion.

Building SaaS products, I always thought email infrastructure would be one of those boring “just call an API and you're done” problems.

It isn't.

While building an email infrastructure platform, I ended up learning that the difficult part isn't actually sending the email.

It's everything that happens around it.

Things like:

•⁠ ⁠handling retries without accidentally sending duplicate emails

•⁠ ⁠processing delivery, bounce and complaint events

•⁠ ⁠maintaining a reliable event timeline

•⁠ ⁠validating sender domains and DNS configuration

•⁠ ⁠separating transactional and marketing traffic

•⁠ ⁠making email logs useful when debugging production issues

•⁠ ⁠dealing with provider-specific behavior

•⁠ ⁠designing an API that developers can integrate with in minutes

One thing I underestimated was how much of an email platform is really an *event-processing system*, rather than simply an email-sending API.

A single email can look something like:

⁠ API request → validation → queue → provider → accepted → delivered → opened → clicked ⁠

And every stage can potentially fail or produce a different event.

The more I worked on this, the more I realized that the “send email” API is probably the easiest part of the entire system.

For other SaaS founders here:

*How are you handling email infrastructure today?*

Did you build your own layer, use a provider directly, or abstract multiple providers behind your own system?

And what part of email infrastructure has caused you the most pain?