Every once in a while you inherit a greenfield problem that feels equal parts thrilling and terrifying. Ours was simple to describe and brutal to execute: build a vendor onboarding experience where no field is hardcoded, every service type defines its own rules, and UI + validation + submission logic are all generated from server-delivered JSON that we lovingly called DNA. This is the story of how that system came to life inside `webapp_frontend`, what it looks like today, and the lessons learned while making it production-ready.