Jae Hyun Song

Backend engineering,
made interactive.

A unified frontend for systems-oriented Java demos, product-style Node.js APIs, and the architecture behind them.

Explore Demos View Architecture

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.

Java demo

Expiring Key Value Store

A session-isolated store with TTL-based expiration, snapshot export, and method-call logging.

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Node demo

Product API Demo

A TypeScript API focused on validation, contracts, product-style routes, and frontend integration.

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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

Read the architecture

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.

Connect

If you'd like to see more of my work or connect professionally, you can find me through the following channels.

GitHub

Resume

Backend engineering,made interactive.