Experience

OfferUp

• United States
• Technology, Information and Internet
• 300 - 400 Employee

• Staff Software Development Engineer/Tech Lead

  • Sep 2019 - Present

  Successfully led transformative efforts across diverse domains including order fulfillment, advertising, and data organization. In the fulfillment team leading the simplify project - analyzing the latency and failure cases of the current system for refactoring and redesigning the order-related microservices: order placement, fulfillment/shipping, returns, and buyer protection claims. Being the tech lead in the ads team is eye-opening and companied by tremendous learning. Below are some high-level statistics of my tenure as the Tech Lead of the ads team. - The team size quadrupled, with maturing engineering practices and increasing velocity. - The efficiency of the core ad server services has increased by more than 50%. Ads backend services are consistently achieving four 9 availability. - Evolved 40% of ads ecosystem architecture without interruption on existing prod traffic and ads revenue. The process is now standard, and the team has applied it repeatedly. - Implemented a few new ads product lines that contribute to substantial revenue growth. After experiencing the pains of data processing in my last two teams, especially in advertising. I was set to build a better data platform that is more efficient, easier to use, and an enabler for faster product development iterations. - Orchestrated successful migration to a new experiment platform across engineering teams. Enabling modern experimentation functionalities. - Pioneered adoption and integration of a new data streaming platform, accelerating engineering velocity by 4x and enabling new applications. - Coordinated collaboration with multiple vendors and guided internal teams to ensure timely completion of the POC and MVP for embedding-based search. Beyond the engineer role, I led 2023 hackathon team in implementing the POC for a new vertical, securing first place in the following ThinkitUp innovation program with a winning business case as the company's 2024 AOP candidate. Show less



Amazon Web Services (AWS)

• United States
• IT Services and IT Consulting
• 700 & Above Employee

• Sr. Software Development Engineer

  • Aug 2017 - Sep 2019

  Designed and Implemented features for SPICE (Super-fast Parallel In-memory Computation Engine), a modern columnar database engine enabling elastic scaling for real-time traffic of AWS QuickSight Analytic Service. • Fully automated data migration for all regions. Designed the availability-zone-based control plane workflow with failures handled by the run-books of normal operations. • Built a framework for late materialization. Implemented a dynamic optimization fitting SPICE’s own storage format to cut the execution time of relevant queries by up to 97%. • Added operator metrics to enable query profiling. This is crucial for analyzing long running queries and for identifying performance bottlenecks. • Built a framework for window functions. Mentored a junior engineer to implement window functions based on this framework. Show less



Teradata

• United States
• Software Development
• 700 & Above Employee

• Engineer/R&D Professional

  • Feb 2001 - Aug 2017

  My journey with Teradata started with the R&D lab at Madison, Wisconsin for 3 years. Then for more than a decade, Teradata gave the freedom to work virtually while my family moved around the country next to research labs and universities. I had great time collaborating with the bright, warm-hearted and open-minded people, coming up with practical solutions for Teradata's share-nothing MPP architecture. Through the years, I implemented, designed, or led many features, such as sparse Join Index, cardinality estimation, Multiple Hash Maps, IN-list optimization which span from parser to query optimizer to query execution engine. With extensive customer problem study, I proposed several forward-looking features prior to my departure. Show less



E-commerce Technology, Inc

• United States
• IT Services and IT Consulting
• 1 - 100 Employee

• Software Engineer

  • Sep 2000 - Jan 2001

  In graduate school, I implemented a web-based email system for the company. Then they invited me to work in the Silicon Valley before the internet bubble burst, I was a backend engineer for the e-commerce platform. In graduate school, I implemented a web-based email system for the company. Then they invited me to work in the Silicon Valley before the internet bubble burst, I was a backend engineer for the e-commerce platform.



IBM

• United States
• IT Services and IT Consulting
• 700 & Above Employee

• Global Service Consultant

  • Jan 2000 - Sep 2000

  While waiting for my visa to U.S, I joined IBM Shanghai and built the yellow-page part of a web portal, using JavaScript and EJB. While waiting for my visa to U.S, I joined IBM Shanghai and built the yellow-page part of a web portal, using JavaScript and EJB.