The machine that re-platformed 190 brand sites.

Diageo owns some of the most recognisable drinks brands in the world, among them Guinness, Smirnoff, Baileys, Don Julio and Aviation Gin, plus 190 brand websites spread across a range of different CMS platforms.

All of them needed re-platforming. Several teams of developers were going to do the migrating, which meant the real deliverable was not any one site. It was the tooling those teams would use.

At 190 sites, hand-checking is not an option, and neither is silently losing content. Metadata, alt text and page content all had to survive the move intact and be provably identical afterwards, across brands with different content models and different source systems.

Grant led the creation of the tooling: data mapping, code generation, testing tools, and crawlers that compared the old and new sites and verified that content, metadata and alt tags matched.

Guinness.com was built as the test project, the reference implementation that proved the tooling and the target architecture before the other brands followed.

A migration capability rather than a migration: several teams re-platforming 190 brand sites onto Contentful and Next.js, with automated verification catching what human review at that volume never would. Guinness.com shipped as the reference.