Inconsistency at scale is expensive. ABN AMRO had multiple teams building interfaces independently, accumulating design debt and slowing delivery. The question was not whether to build a design system, but how to make it something teams would actually adopt and maintain.

Emerald was built as a living system: modular components with clear rules, documented in one central place, accessible to both design and development. The goal was not uniformity for its own sake. It was enabling teams to validate ideas fast in the first design diamond, and ship reliably in the second.