Chloe Lin contributed to the rubyforgood/stocks-in-the-future repository by enhancing backend reliability and test coverage through targeted improvements in Ruby on Rails. She developed realistic portfolio transaction seed data, introducing varied deposits, withdrawals, and trades to better simulate user activity and strengthen baseline tests. Chloe refactored purchase stock logic to ensure accurate fund calculations, addressing both buying and selling scenarios. She also reverted a faulty fund sufficiency validation and removed a broken test, restoring correct balance checks. Through careful code cleanup and database seeding, Chloe improved maintainability and enabled safer refactoring, demonstrating depth in backend development and Ruby programming.