Chang Chen

Software Engineer Intern @Balanx-Bio

San Jose, CA, US

I worked on an IoT coffee personalization system that analyzes saliva biomarkers to recommend optimal coffee recipes. We onboarded 500+ beta users during testing.I developed ESP32 embedded firmware in C++ using FreeRTOS for multi-threaded sensor data collection, implementing error handling that significantly reduced data corruption. I integrated MQTT messaging with automatic reconnection to stream data reliably from devices to the cloud.On the backend, I built a Python FastAPI microservice to process incoming sensor data with connection pooling and batch writes to PostgreSQL on AWS RDS. I deployed everything on AWS EKS using Docker and Terraform, set up CI/CD pipelines through GitHub Actions, and wrote tests to ensure system reliability.The biggest challenge was building a system that bridges embedded hardware and cloud infrastructure while maintaining reliability at every layer. I learned how to design IoT systems where data integrity from sensor to database is critical, and how important testing and monitoring are when hardware and software need to work seamlessly together.

The University of Nottingham Ningbo China

Bachelor of Arts, International Communication

Northeastern University

Master of Science, Computer Science