Over a two-month period, contributed to Automattic/wp-calypso by implementing Passport integration for login and marketplace checkout, introducing new styles, components, and updated routing to streamline user experience. Ensured robust functionality and design compliance through comprehensive test coverage using React and TypeScript. Later, addressed backward compatibility in WordPress/gutenberg by developing a PHP shim for submenu icon rendering, preventing fatal errors during core deprecations and aligning with evolving WordPress standards. Enhanced reliability by adding and updating PHPUnit tests, supporting a smooth upgrade path for themes and plugins. Demonstrated a full stack approach, balancing frontend improvements with backend stability and test-driven development.