Jimmy Cook worked on the Skyscanner/backpack repository, focusing on enhancing the BpkCardList carousel’s alignment and responsive spacing. He introduced CSS variables to control spacing and card gaps, improving layout adaptability across mobile and various breakpoints. Using React, TypeScript, and SCSS, Jimmy addressed alignment issues to ensure consistent user experiences on different devices. He also migrated components like BpkFieldset and BpkLink to TypeScript, strengthening type safety and maintainability. Additionally, he upgraded dependencies and tooling, including Storybook and ESLint, to reduce technical debt. His work resulted in a more stable design system and smoother, more responsive UI components for users.