Nain Puissant developed Yarn Berry catalog protocol support for the nrwl/nx repository, enabling catalog-aware dependency resolution and validation within Yarn workspaces. Leveraging Node.js and TypeScript, Nain introduced a YarnCatalogManager and integrated it into the existing catalog infrastructure, aligning Yarn support with the pnpm workflow for cross-package-manager consistency. The implementation included robust validation logic and descriptive error messaging for missing or invalid catalogs and packages, reducing manual maintenance. Nain ensured reliability by executing an extensive test suite covering parsing, resolution, validation, and catalog version updates, demonstrating depth in both technical execution and attention to maintainability in full stack development.