How to Manage and Create Composable Email Templates with Components

Every product team eventually hits the same wall with email: a welcome.html file ballooning into a 1,200-line monolith, copy-pasted styles across templates that never quite match, a marketing tweak that breaks billing emails, and an A/B test that takes a week to ship because the "templating engine" lives in a folder no one wants to touch. Email is one of the last places in modern product engineering where we still tolerate this. We componentized our UI years ago. We componentized our backends. B