Developed full-stack air quality systems for county and state governments to regulate and analyze over 100K industrial users using Spring, and SQL Server. The system improves the decision-making process by over 30%.

Built and normalized/denormalized databases and table structures, maintained over 1000 tables and 10M+ records. Improve future development productivity by reducing the effort of maintaining duplicate data.

Refactored SQL scripts and service code, boosted the performance by over 50% for 20+ queries across the system.

Improved future productivity by at least 50% by decoupling the validation service from the sports betting service.

Used Spring Boot Cache and Redis to implement the cache mechanism. Cached 20+ most commonly called APIs in the system and increased the average response time across all APIs from 1s to 200ms.

Improved the availability of odds information puller service by introducing redundancy and ZooKeeper. Reduced the time to recover service from 20 minutes to within 1 minute.

Mentored and assisted junior developers; conducted code reviews weekly to ensure the high quality of code.