Worked on the mongodb/node-mongodb-native repository to enhance server selection and read preference handling for MongoDB replica sets. Focused on improving reliability by implementing a refined calculation of commonWireVersion based on each server’s maxWireVersion, which aligns client behavior more closely with server capabilities and reduces read-time errors in mixed topology environments. Developed comprehensive tests in TypeScript to validate wire-version calculations and ensure correct read-preference behavior across primary and secondary deployments. Collaborated on code reviews and contributed to maintainability improvements, applying full stack development and testing skills to strengthen consistency and correctness in MongoDB client-server interactions without introducing regressions.