Hi, I'm Willy 👋
Hi everyone ! My name is Chun Chieh (Willy) Chang 張竣傑, and I’m from Taiwan 🇹🇼.
CCC

About

Software engineer with experience building scalable web platforms and distributed systems. Skilled in full-stack development, cloud infrastructure, and real-time data pipelines. Proven ability to deliver production-grade solutions across startups, academia, and research. Passionate about improving performance, developer experience, and system reliability.

Work Experience

T

Tiktok

April 2025 - Present
Frontend Engineer (Privacy Product)
Incoming Frontend Engineer focusing on privacy product development.
K

Kocree

May 2024 - August 2024
Full Stack Developer Intern
Developed an AI-driven music platform, Muosaic, using Svelte, Nest.js, and PostgreSQL, deployed on K3s with NGINX ingress. Migrated user authentication from Keycloak to Stytch to streamline user onboarding and overhauled the system’s data model to improve privacy and access control. Enhanced observability with Promtail and Loki, visualized in Grafana.
U

University of Illinois Urbana-Champaign

March 2024 - November 2024
Full Stack Developer
Developed an attendance management web application serving over 5,000 students across 30+ courses. Refactored the backend into a modular MVC architecture using Express.js and converted the codebase to TypeScript, improving maintainability, unit testing, and type safety. Achieved 95% test coverage using Jest.

Education

U

University of Illinois Urbana-Champaign

2022 - 2024
Master of Computer Science
F

Fu Jen Catholic University

2015 - 2019
Bachelor of Science in Computer Science

Skills

Typescript
Java
C++
Swift
Python
Go
Node.js
React
Next.js
Svelte
Express
NestJS
Gin
Flask
FastAPI
MySQL
Postgres
ScyllaDB
MongoDB
Neo4j
Redis
Kafka
Celery
Flyte
OpenSearch
Debezium
Docker
Kubernetes
AWS
GCP
Terraform
Grafana
Linux
Github Actions
My Projects

Check out my latest work

I've worked on a variety of projects, from web application to complex distributed system. Here are a few of my favorites.

Hybrid In-Memory Serverless Orchestrator

Hybrid In-Memory Serverless Orchestrator

Developed a serverless orchestrator with a hybrid in-memory data store and critical node selection algorithm

AWS Lambda
MemoryDB
DynamoDB
Report
Source
Fault-Tolerant Distributed System

Fault-Tolerant Distributed System

Developed a scalable, fault-tolerant MapReduce framework and a Raft-based key/value store for consistent, reliable operations.

Golang
Raft
RPC
Fault Tolerance
Load Balancing
Source
Cloud-Native Microservices Platform

Cloud-Native Microservices Platform

Developed a cloud-native platform with 5 microservices, optimizing performance, reducing latency, and processing 45M+ financial records.

GCP GKE
Gin
FastAPI
Spring Boot
gRPC
Flyte
Celery
Kafka
Terraform
ArgoCD
Navigation Chatbot

Navigation Chatbot

Built a chatbot to interpret city distance queries, using an AWS Lambda function to calculate shortest routes with data stored in DynamoDB.

Python
AWS Lambda
API Gateway
DynamoDB
Cognito
Lex
Resume
LinkedIn