YouTube Premium, Commerce, Nitrate

Built a RESTful server (Java) and a GraphQL server (Node.js). Features JWT

authentication, OAuth SSO, mobile push notification, WebSocket API, real-time data/message

delivering.

• Lead engineer of a high performance cross-platform mobile app (React Native). Integrated with

GraphQL, Apollo cache, React Redux, Firebase Cloud Messaging, Jest etc.

• Implemented a real-time chat micro-service using Pubsub (Message Queue) & GraphQL Subscriptions

(WebSocket). Supports cross-platform communication (Web, iOS, Android)

• Optimized Sequelize ORM generated SQL query with subquery and indexing.

• Responsible for development, testing, release and support of mobile apps (iOS: Swift, Android: Java) Worked closely with UI/UX designers and clients to implement features and provide feedback

• Refactored the iOS app from MVC to MVVM for better modularization, and adopted ReactiveX/RxSwift to optimize async operations and event/data streams

• Developed and maintained components for LyricFind API: front-end development (JavaScript, jQuery, HTML5), server-side development (Java, SQL), adding new features and application logics, maintaining data persistence and bug fixing

• Migrated all API data from old databases to the newly developed Solr database, created SQL scripts to maintain the data integrity and indexed data to support faster Solr data search

• Contributed to development of tools to covert row-organized tables to column-organized tables in IBM DB2 with BLU Acceleration to allow optimized in-memory computing (C++, SQL)

• Created scripts to perform functional testing for “DB2 Cloud” on Amazon EC2 platform (Perl, SQL)