AI/Python exploration
ghostcat
A private reflection space that parses natural language into mathematical emotional vectors, then renders those values as a public abstract signature.
Visit ghostcat
Jae Hyun Song · Backend-Focused Software Engineer
Systems-minded engineering
across Java, Node.js, and AWS
This portfolio brings together interactive backend demos, production-style APIs, and architecture work designed to show how I build across the stack.
Spring Boot · Fastify · Next.js · TypeScript · AWS
Technologies
Built across the stack
The frontend, backend services, and infrastructure used to design, implement, and deploy this platform.
Demos
Featured demos
Interactive backend demos designed to make systems behavior, API design, and execution flow visible.
Architecture
One frontend, separate backend tracks
The platform uses a unified React frontend with distinct backend paths: Java for systems-oriented demos and Node.js for product-style APIs.
• Real backend execution over frontend simulation
• Thin API layers over isolated domain logic
• Session-based demo instances for per-visitor isolation
• Shared infrastructure for logging and platform behavior
Platform flow
Next.js Frontend
Java Demo Service
Node API Service
AWS Deployment
About
Backend-focused. Product-aware.
I'm a software engineer focused on backend systems, API design, and building technical demos that make engineering ideas tangible. This portfolio showcases how I approach system architecture, implementation, and frontend presentation as a cohesive product.
