No wireframes, no handoff
The CCS rebrand was built entirely in the GOV.UK Prototype Kit before anything was proposed for the live product. That choice shaped the process. Colour, navigation, footer taxonomy: every decision was tested in a working prototype, not a static mock.
The kit made global changes fast. SCSS variables meant a primary colour swap propagated across the entire prototype in minutes. Multiple layout configurations could be instantiated and compared without engineering cost. The prototype behaved like a real service. Real navigation, real content, real interaction.
Research instruments, not edge cases
The prototype included distinct header configurations: a standard version, a beta variant with the GDS phase banner, a hero version integrating a search bar into the header, dropdown-capable navigation. These were not edge cases. They were research instruments. Each variant available for parallel testing against specific tasks so navigation decisions could be grounded in evidence rather than preference.
The footer redesign started from an information architecture problem. The existing footer reflected organisational structure, not user needs. Content that users thought of as related was separated. The new structure organised content into four logical groupings: Products and support, For buyers and suppliers, Corporate information, Digital platforms. Task-oriented, not org-chart-oriented.
Documentation as specification
The result was a documented design system: twelve component and prototype specifications covering colour, typography, spacing, buttons, cards, navigation, and footer. Each specification included exact hex values, contrast ratios, spacing constants, and implementation-ready code. Design decisions were traceable to their rationale.
Research findings were trustworthy because they came from something that behaved like the real thing. Not filtered through the gap between a wireframe and a working product. The prototype kit documentation remains the specification of record for the brand system.