Yizhao Li

Built the employee workflow module for a 300+ person corporate platform, covering multi-level approval routing, status tracking, and notifications; reduced average approval turnaround by 1 hour. Built the React/Redux frontend with reusable components and designed RESTful APIs with Express.js to support approval flow operations end-to-end. Designed the approval flow as a configurable state machine; transition rules stored in MySQL and enforced server-side, making the flow extensible without code changes. Used Redis to cache in-flight approval states and intermediate results, reducing redundant DB reads during frontend polling; invalidated cache on each state transition to maintain consistency.

Built an electronic detonator storage monitoring system with real-time temperature and humidity alerts, ensuring safety compliance across multiple warehouses. Deployed services to AWS EC2, configured S3 automated backups, and set up CloudWatch alarms to monitor resource health and reduce unplanned downtime. Built the front end with React.js and Tailwind CSS, using ECharts for real-time dashboards and anomaly visualization. Refactored Spring Boot modules and MyBatis SQL mappers to remove duplicated query logic; added JUnit tests on refactored paths to improve maintainability and deployment stability.