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Lee Sang-Heon

Full Stack Developer & Game Programmer

A passionate full-stack developer specializing in game programming, web development, and Discord bot creation. I build Unity-based games and web applications using React and Java, while actively exploring and implementing emerging technologies from communities like X and GeekNews.

About Me

I bridge the worlds of game and web development with a focus on exceptional user experiences. I actively explore cutting-edge technologies and deliver innovative solutions through creative problem-solving.

Game Development

Experienced in game development using Unity, C#, and WebGL, as well as in game security.

Unity
C#
WebGL
Game Security
Web Development

Pursuing full-stack web development with React, Java, and FastAPI, focusing on user-centered UI/UX design.

React
JavaScript
FastAPI
Python
Chatbot Development

Creating services that prioritize user interaction through Discord bot and KakaoTalk bot development.

Java
JDA
Spring
Flask
Python
Kakao i Open Builder
Continuous Learning

Exploring the latest tech trends from X(Twitter) and GeekNews, and applying them to real projects.

Latest Tech
Problem Solving
Innovation
Challenge

Skills & Technologies

Delivering effective solutions with a versatile tech stack

Indicates frequently used technologies

Frameworks & Libraries

React
Vue.js
Discord API
FastAPI
Axios
MUI
Node.js
Flask
Express
Spring

Languages

Java
Kotlin
JavaScript
TypeScript
HTML/CSS
C#
C++
Python
PHP
SQL

Tools & Platforms

Git
Unity
Linux
Claude Code
MongoDB
Slack
Discord
Mattermost
Teams
Figma
MySQL

Projects

Projects I've built, shipped, and learned from.
AngelicBusterBot(Abbot)

AngelicBusterBot(Abbot)

2022.04 - Currently in Service

A Discord chatbot that provides MapleStory-related information to users. Utilizes Nexon Open API to deliver real-time game information, character search, and guild details. Has been in service for approximately 3 years, currently serving over 180,000 users across about 4,700 servers.

Java
JDA
Maven
Nexon Open API
jsoup
REST API
Gson
Linux
JavaScript
FastAPI
React
MUI
axios
Federation of Korean Trade Unions Daegu Regional Headquarters Website

Federation of Korean Trade Unions Daegu Regional Headquarters Website

2025.03 - 2025.06

Official website for the Daegu branch of the Federation of Korean Trade Unions. Mainly focused on course registration functionality, handled overall website development as commissioned work. Key development features included full frontend and backend development of the course registration system and admin system.

React
JavaScript
Python
FastAPI
MongoDB
PHP
Linux
🔗Website
StockTalk

StockTalk

2023.09 - 2023.12

An AI-powered KakaoTalk chatbot that predicts daily closing price fluctuations compared to the previous day's closing price using hourly news articles and stock price movements. Implemented with a Python Flask server connected to Kakao i OpenBuilder to analyze user speech intent for more precise operations. Dynamically generates graph images based on AI-generated results and attaches them to custom-designed KakaoTalk messages for seamless user experience.

Kakao i OpenBuilder
Python
Flask
Linux
Java
jsoup
Konlpy
COCA : Group and Personal Schedule Management Sharing Service

COCA : Group and Personal Schedule Management Sharing Service

2024.02 - 2024.06

A community-based collaborative calendar that helps manage group and personal schedules and finds available time slots among group members. Designed and implemented an intuitive UI to create a user-friendly service. Utilized both brute-force and interval merging algorithms appropriately to find available time slots as quickly as possible.

JavaScript
React
Axios
Java
Spring
MySQL
GitHub
Gemini Tetris

Gemini Tetris

2022.09

A fan game for the virtual group RE:REVOLUTION. Developed as a commissioned birthday fan game for a group member. Developed using Unity and built with WebGL to allow gameplay on the web. Added button UI for mobile environments in addition to PC to ensure playability across various platforms.

Unity
C#
WebGL
🔗Play

Experience

Professional experience and key accomplishments.
2021.12 - 2023.02

Research Engineer

Wellbia.com Co., Ltd.
A company developing Xigncode3, an anti-cheat module and program for games.
Applied C++ security modules to Unity and Android platforms
Implemented cross-platform integration between C++ and Java using JNI framework
Discovered and proposed countermeasures for global offset vulnerabilities through Unreal Engine (UE4) source code analysis
Researched ACTk Obscured Variable analysis and memory tampering prevention mechanisms
Built development environment automation scripts using Windows PowerShell
2023.03 - 2024.08

Vice President & Reverse Engineering Mentor

Kumoh National Institute of Technology Information Security Club BOSS
Provided mentoring to juniors based on game security knowledge acquired while working.
Designed reverse engineering curriculum and created practical materials
Mentored static analysis using debugging tools (IDA)
Mentored dynamic analysis using memory tampering tools (Cheat Engine, etc.)
Conducted basic security concept education accessible to non-majors
Organized internal CTF and created dynamic analysis-related challenges
2023.07 - 2025.02

Undergraduate Researcher

Signal Processing and Intelligent Network Lab
Participated in various laboratory projects as an undergraduate researcher.
Frontend development within projects
UI/UX design within projects
Research on integrating markdown editors and formula editors

Achievements & Licenses

Recognition, certifications, and key accomplishments
Award
Selected for MapleStory Partners (for Developers) :: AngelicBusterBot(Abbot)

Nexon

June 2024

Award
KIT Engineering Fair Bronze Prize

Kumoh National Institute of Technology LINC3.0 Project Group

November 2023

License
Information Processing Engineer

Human Resources Development Service of Korea

September 2024

License
JLPT N2

Japan Foundation

January 2025

Activity
CO-UP CAMPUS CHATBOT HACKATHON Participation

Ministry of Education and 6 Other Organizations

January 2024

Education

Academic background and training
  • July 2025 - Present

    In Progress
    SSAFY

    14th Cohort

    Mobile Track

  • March 2019 - February 2025

    Graduated
    Kumoh National Institute of Technology

    Bachelor of Engineering

    Department of Computer Software Engineering

  • March 2016 - February 2019

    Graduated
    Daegu Siji High School

    High School Diploma

    Science Track

Let's Work Together

Open to project inquiries, collaboration proposals, and job opportunities.

© 2026 Lee Sang-Heon. All rights reserved.

Built with Next.js, FastAPI & Claude Code.