- Developed 50+ Restful APIs: Collaborated with product and engineering team members to define and develop new product concepts. - Developed Community login APIs: Familiar with the OAuth2 process, used to connect Facebook, Google, Line, and Apple login. - Developed Unit / Feature Testing: Increased legacy code test coverage from 0% to 50%. - Designed Cache Mechanism: Leveraged Redis cache optimization techniques to boost website speed and performance. The API response time dropped from 60+ seconds to less than 10 seconds. - Designed hierarchical structure table: McDonald's has a multi-level store structure covering 7,000+ stores, 150+ cities, and 30+ countries in the world. Designed a closure table to handle the hierarchical structure. - Familiar with AWS Services(SES, SQS-FIFO, SNS): Sent more than 7000+ e-mails, recorded open letters, complaint rates, and bounce rates. - Implemented Automated Testing: Integrated tests in CI / CD development process, and reduced manual testing time. - Formulated Commit Log Standard: Reduced consulting fees and development hours. - Assigned Mentor: Assisted internal staff and intern with troubleshooting to quickly and effectively resolve software issues.

- Implemented DB Read / Write Separation Mechanism: The demand for reading DB in Yahoo Movies is much greater than that of writing DB, so the DB was split into reading and writing databases. - OnBoard Roadmap: Created technical workflows in wiki to support education and training of newly hired employees.