I'm a software engineer based in Japan, primarily focused on backend engineering.

I enjoy understanding not only how to make software work, but also why systems are designed the way they are.

I prefer learning technologies by integrating them into real applications and improving those applications through small, reviewable changes.

Korea National Open University

• Department: Prime College, Division of Advanced Engineering (AI)
• Degree: Bachelor's Degree (March 2026 ~ Present, Expected February 2028)

Yeungjin University

• Department: Division of Computer Information (Cloud/Japan IT)
• Degree: Associate Degree of Engineering (March 2023 ~ February 2026)
• Micro Degree: AI + Japan IT

TIS West Japan Inc.

• Position: Software Engineer
• Period: April 2026 – Present

A camera-free, wearable-free monitoring prototype using 60 GHz mmWave radar.

🏆 JPHACKS 2026 Hack Day Audience Award — Hiroshima venue · 3-member team

IBUKI combines radar sensing, real-time visualization, alerts, and on-device AI, including board-originated Wi-Fi notifications. Hardware checks used adults, not infants; it is not a medical device.

• Built and refined the React/TypeScript dashboard, displaying live Brain status and alerts via WebSocket while distinguishing reconnecting, stale data, and sensor disconnection.
• Built the Windows one-command launcher for environment setup, dashboard builds, server startup, and browser opening.
• Added native Windows alarm playback and integrated existing alarm acknowledgment flows.
• Developed an offline radar-data workflow for capture parsing, quality checks, Parquet datasets, signal/STFT visualization, denoising and CNN-sensitivity comparisons, and standalone HTML reports.
• Created a standalone 2D Radar Explorer, interactive 3D crib/synthetic-position visualization, and a guided three-step product walkthrough. These are offline experiments and conceptual demos, not validated infant tracking.
• Added automated tests and browser-based regression checks for the dashboard and analysis tools.

XERJ Corpus Hub: My Windows launcher and native alarm playback contribution was selected for inclusion. Contributor profile.

Technologies: React · TypeScript · WebSocket · Python · FastAPI · Parquet · Three.js · Infineon PSOC Edge E84

Project & Demo · WebSocket UI PR #39 · Windows/Alarm PR #66 · Dashboard PR #77 · Data Pipeline PR #112 · Radar Explorer PR #119 · Showcase PR #126

Reconstructing a 2024 AI hackathon prototype as a privacy-safe and reproducible software project.

The current repository is an independent reconstruction using synthetic CRM data and does not contain the original corporate dataset or proprietary source files.

• Public / private data boundaries documented
• FastAPI health endpoint and automated test added
• Historical lead / note data relationships reconstructed
• Public aggregate CRM profile documented
• Privacy-safe synthetic data generator calibrated to observed aggregate behavior

• Leakage-safe machine-learning evaluation
• Reproducible preprocessing and feature pipelines
• Prediction and explanation APIs
• React / TypeScript dashboard
• Human-reviewed LLM-assisted outreach
• Automated tests, Docker, and CI

🚧 Current phase: calibrated synthetic data foundation ➡️ Next: leakage-safe preprocessing · reproducible EDA · model baselines

➡️ Follow the Reconstruction

Helping seniors and their families stay connected through asynchronous video communication.

An 8-member Java/JSP team project where I primarily contributed as a development / system design member.

• Designed application and server-side processing flows
• Structured the Servlet → Logic → DAO processing model
• Designed video playback and automatic reaction-recording behavior
• Defined unread / read state processing rules
• Created implementation specifications
• Designed functional, boundary, and exception test cases
• Reviewed implementation against agreed specifications
• Coordinated design and specification decisions within the team

The public repository also separates credentials and runtime-generated data from source control through environment-based configuration and repository hygiene practices.

Java 21 · Jakarta Servlet · JSP JavaScript · MySQL 8 · Apache Tomcat 10

➡️ Explore Tsunagaroom

A social dining platform connecting people through shared meals and local events.

A 4-member team project built as separate frontend, backend, and AI-service repositories.

• Initial entity design
• Authentication flow
• Album backend
• Chat-room entity relationships
• Comment DTO fixes
• S3 image deletion behavior

• Next.js frontend and NestJS backend
• PostgreSQL + TypeORM persistence
• JWT and Google / Kakao OAuth
• Real-time chat with Socket.IO
• AWS S3 image handling
• FastAPI AI-service integration
• Docker and GitHub Actions
• AWS ECS / ECR deployment workflow

Next.js · React · TypeScript · NestJS PostgreSQL · TypeORM · FastAPI Docker · AWS · GitHub Actions

➡️ Frontend Repository ➡️ Backend Repository

flowchart LR
    A["Build Features"]
    --> B["Design Boundaries"]
    --> C["Improve Reliability"]
    --> D["Scale with Cloud"]
    --> E["Apply AI"]

    style C fill:#d1fae5

My current focus is moving from simply implementing features toward understanding the larger engineering concerns around them.

Learning, working, and adapting across different countries and cultures.

These experiences have strengthened my adaptability, cross-cultural communication, and ability to work in unfamiliar environments.

I prefer learning technologies by integrating them into real applications rather than studying them only in isolation.

When introducing a new technology or architectural pattern, I try to understand:

Why is it needed? What problem does it solve? Where should it belong? What trade-offs does it introduce?

I value incremental improvement:

Build → Find a limitation → Understand → Improve → Test → Review → Repeat

My goal is to grow into an engineer who understands both implementation details and the larger systems around them.