<Hyun/>
— ABOUT
Backend engineer who turns manual business
workflows into reliable software with
Kotlin, Java, Spring Boot, Python, and FastAPI.
AWS Certified DevOps Engineer – Professional.
Passionate about clean code and continuous learning.
workflows into reliable software with
Kotlin, Java, Spring Boot, Python, and FastAPI.
AWS Certified DevOps Engineer – Professional.
Passionate about clean code and continuous learning.
"Clean code always looks like it was written by someone who cares."
- Robert C. Martin (Clean Code)
- Robert C. Martin (Clean Code)
Download Resume
Clean Code
Writing maintainable and scalable code
Web Application
Full-stack web development expertise
Backend System
Robust API development and database design
Responsive Design
Mobile-first approach to UI/UX
— EXPERIENCE
Software Developer, Operations Automation
SB Trading Corporation
May 2026 - Present
Kansas City area, USA
•
Built a React/TypeScript and FastAPI platform for purchasing and inventory allocation across four retail stores, replacing an Excel-based ordering workflow.
•
Implemented configurable replenishment rules, vendor-specific Excel exports, and workbook comparison tools to validate ordering calculations.
•
Separated calculation workers from the API, with durable job tracking, duplicate-request protection, and auditable quantity changes.
•
Integrated BigCommerce order lookup, approval-gated store-credit refunds batched across stores, and allocation cart previews behind a shared request-coalescing cache, plus report emailing with role-based access.
Technologies Used
Python
FastAPI
React
TypeScript
SQLite
BigCommerce API
Docker
Render
pytest
Playwright
Research Intern
University of Missouri - Kansas City
August 2025 - May 2026
Kansas City, MO, USA
•
Built and evaluated biomedical knowledge graphs from clinical reports, EHRs, and imaging data for entity linking and explainable multimodal models.
Technologies Used
Python
Knowledge Graphs
Multimodal AI
Explainable AI
Website Coordinator Intern
TRTCLE
January 2025 - May 2025
Remote
•
Replaced a manual Excel workflow for 300+ course records with Python automation.
•
Collaborated in a five-person agile team on legal-education website content and navigation.
Technologies Used
Python
Excel
Jira
Confluence
Software Engineer Intern
The Catholic Univ. of Korea, Seoul St. Mary's Hospital
June 2024 - December 2024
Remote
•
Co-built the Spring Boot backend of an ERAS surgical-checklist system with another backend engineer.
•
Implemented patient registration, checklists through discharge, filtered views, and per-patient Excel exports to replace paper records.
Technologies Used
Java
Spring Boot
Docker
GitHub Actions
Jenkins
Backend Developer
Menteetor
January 2024 - August 2024
Team of four
•
Built university-email verification for 309 Korean universities, WebSocket chat, and Redis caching for chat reads.
Technologies Used
Java
Spring Boot
Spring Security
MySQL
Redis
Elasticsearch
AWS
— SKILLS
Java
Kotlin
Python
JavaScript
TypeScript
SQL
Spring Boot
Spring Data JPA
Spring Security
Querydsl
MySQL
PostgreSQL
MongoDB
Redis
React
Next.js
Angular
HTML
CSS
Tailwind CSS
Docker
Figma— PROJECTS
Bellight - Laundromat Ordering & Payments
Founding-team backend for online ordering and card self-service at two laundromats (eight machines).
KEY FEATURES
•
Stripe Terminal in-store and Stripe Connect online, with persisted idempotency for retries
•
Built MQTT machine control and persisted machine state for recovery after restarts
•
Used Spring Modulith boundaries and a transactional outbox to Kafka for cross-module events
•
Validated database changes with MySQL Testcontainers and Flyway checks in CI
TECH STACK
Kotlin
Spring Boot
Spring Modulith
MySQL
Stripe
Kafka
MQTT
SB Trading - Purchasing & Inventory Platform
Purchasing workspace for replenishment and allocation across four retail stores (staff login required).
KEY FEATURES
•
Moved Excel-based ordering into a React and FastAPI app with configurable rules and vendor exports
•
Separated calculations into durable workers so review screens remain responsive
•
Added role-based approval, quantity-change history, and BigCommerce order lookup and refunds
•
Preserved input snapshots and compared calculations with existing workbooks
TECH STACK
React
TypeScript
FastAPI
SQLite
Docker
Render
pytest
Playwright
JobPilot - Personal Job Search Dashboard
A personal dashboard that brings job discovery, resume matching, and application tracking into one workflow.
KEY FEATURES
•
Collects job postings from multiple applicant tracking systems
•
Integrates AI-assisted resume matching with requirement-level explanations
•
Generates tailored resumes from existing experience and assists with application forms
•
Runs synchronization and scoring through a background worker
TECH STACK
Next.js
TypeScript
SQLite
Drizzle
Python
Playwright
Claude API
Seoul St. Mary's Hospital - Patient Records System
Spring Boot backend for an ERAS surgical-checklist system, covering patient records and clinical workflows.
KEY FEATURES
•
Co-built the backend with another engineer, covering patient registration and surgical checklists through discharge
•
Implemented filtered patient views and per-patient Excel exports to replace paper records
TECH STACK
Java
Spring Boot
Spring Security
Spring Data JPA
QueryDSL
MySQL
AWS EC2
Docker
Nginx
Kansas Korean - Community Meetup App
Community meetup app serving Kansas and Philadelphia, live since July 2026.
KEY FEATURES
•
Grew to 73 members, 70 meetups held and 507 RSVPs by September 2026
•
Implemented Kakao and Google login, recurring schedules, and in-app and Web Push notifications
•
Added reviews, photos, cost splitting, AMC showtime matching, and Korean/English/Spanish with on-demand Claude translation
TECH STACK
Next.js
PostgreSQL
Drizzle
Redis
Vercel
PWA
Church Website & Member Platform
Public church site and authenticated member area with content tools for administrators.
KEY FEATURES
•
Built a replacement for the church's hosted website with Astro on Cloudflare Workers and D1
•
Implemented session authentication with Google and Facebook login, role-based administration with sign-up approval, and small-group reports with CSV export
•
Built a content editor that commits changes to GitHub for automatic deployment
TECH STACK
Astro
Cloudflare Workers
D1
GitHub
Open Source Contributions
Merged pull requests to Java and Kotlin open-source projects in September 2026.
KEY FEATURES
•
Spring Boot: fixed cookie handling in the reactive Apache HttpComponents client (#51724)
•
MockK: negative verifications now wait out the whole timeout, closing an issue open since 2019 (#1559)
•
Redisson: added Redis server TIME to RKeys across sync, async, Reactive and RxJava APIs (#7358)
•
Also merged: Micronaut Core (#13092), Resilience4j (#2522), Jedis (#4735), Floci (#3354)
TECH STACK
Java
Kotlin
Spring Boot
Redis
JUnit
Gradle
StormVision-3D - AI-Driven Disaster Education Platform
AI-driven platform for hurricane formation and hazards visualizations using interactive, scientifically grounded 3D visuals.
KEY FEATURES
•
Integrated live NOAA stream ingestion for real-time and historical hurricane comparison
•
Grounded visualizations in authoritative public data from NOAA, FEMA, and NASA
•
Earned 3rd Place in the AI Agent Track at Hack-A-Roo (UMKC Graduate Capstone)
TECH STACK
AI Agent
3D Visualization
Python
NOAA API
Geospatial Data
Menteetor - Mentor-Mentee Matching Website
Mentorship matching platform for 309 Korean universities, implementing university email authentication for secure, student-only access
KEY FEATURES
•
University-verified accounts with secure authentication using JWT
•
Real-time chat with file & image sharing
•
Infinite scrolling for seamless content browsing
•
Trending keywords for popular topics discovery
•
Push notifications for chat and mentoring updates
TECH STACK
Java
Spring
Spring Security
MySQL
Redis
FCM
WebSocket
ElasticSearch
EC2 RDS S3
Docker
Animalysis - Fitness Management Website for Pets
Helps pet owners manage health records, track wellness trends, and receive personalized workout, diet, and supplement suggestions for each animal.
KEY FEATURES
•
Health record management for each pet (e.g., vaccination history)
•
Graph-based tracking of health and fitness trends
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Personalized workout, meal, and supplement suggestions
•
PDF export of health records for vet visits
TECH STACK
TypeScript
React
Next.js
Supabase
PostgreSQL
Tailwind CSS
CityLink - AI-Powered Travel Assistant Platform
Smartly suggests destinations and nearby cities, auto-connects travelers in real time, and provides AI-driven tips on attractions, restaurants, and hidden gems.
KEY FEATURES
•
Smart destination search with Google Maps integration
•
Real-time chatrooms connecting travelers visiting the same location
•
AI-powered recommendations for attractions, dining, and hidden gems
•
Personalized chatbot guidance with direct navigation links
TECH STACK
JavaScript
React
Python
Flask
WebSocket
OpenAI API
Google Maps API
CodeMate - Personal Code Mentor System
CodeMate connects with GitHub to analyze, improve, and polish code with AI assistance, while building stronger code intuition through challenges and gamified practice.
KEY FEATURES
•
GitHub integration for instant code analysis
•
AI-powered suggestions to refine code
•
Practice optimization through challenges
•
Gamified learning with progress tracking
TECH STACK
Java
Spring
SQLite
Auth0
SonarQube
Git API
OpenAI API
Docker
View More on GitHub
— GET IN TOUCH
Let's connect!
I'm always open to exciting opportunities — whether
it's full-time roles, freelance projects, tech
collaborations, or even a friendly conversation.
it's full-time roles, freelance projects, tech
collaborations, or even a friendly conversation.
Reach Me on LinkedIn