Architecture

4 posts on architecture for AI agents that send and receive email.

30 July 2026 · 4 min read

Transactional and marketing email in one API

Running both kinds of mail through one vendor is fine. Running them through one sending reputation is not. Here is what has to be shared and what has to be kept apart.

30 July 2026 · 4 min read

Email automation as code

A lifecycle sequence is a program that decides who gets mailed. Here is what it looks like as a YAML file in your repository, reviewed in a pull request and pushed from CI.

22 May 2026 · 4 min read

Transactional email versus marketing email, and why the split matters

The difference is not tone, it is consent, reputation, and legal obligation. How to classify a message correctly and how to separate the two streams in DNS.

24 April 2026 · 5 min read

Idempotency keys and retries for transactional email

Why retrying a send is dangerous, how to choose a key that is stable across retries, and how to build a retry policy that never mails anyone the same thing twice.