Lee Sang-Heon

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.

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.

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.

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.

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.

An AI-powered smart meeting platform. Combines a LiveKit-based video conference with real-time STT subtitles, auto-generated meeting summaries, agenda management, and speaker queue control in a single room. Runs faster-whisper on CUDA for real-time Korean transcription with speaker diarization and hallucination filtering, and uses a self-hosted TURN server to keep the connection stable across network conditions.

A fintech personal-finance app that combines social login, bank-account linking, AI-driven budget management, and goal-achievement visualization videos in one flow. Monthly income is automatically allocated across weeks and recalculated against the remaining span when a goal is extended, and a LangGraph-based AI chatbot handles merchant classification and budget advice. Goal visualization videos are produced by a self-built image-to-video pipeline service that I designed and still operate (sketch.pyan.kr), which returns MP4, WebM, and GIF assets over a CDN.

An agent-agnostic sidecar that drops an AI-powered live-edit overlay on top of a running web app. A single <script> tag injects a Shadow DOM overlay; users click a UI element and describe a change in natural language, and the configured AI agent CLI edits the actual source, runs the build, and either rsyncs the result to the live app or opens a PR. Ships with five agent adapters (OpenClaw, Claude Code, Codex, Aider, Gemini) and Next.js, Vite, Astro, and SvelteKit examples, and is published to npm as a self-hosted package with HMAC actor signing and a systemd template. In 2026-05, the project was accepted into the official pollinations.ai OSS app showcase at Flower Tier.

A web-based algorithm problem-solving platform powered by a LangGraph AI coding agent. The agent assists in real time with code writing, debugging, and hints, while its full execution flow is traceable per session through a Langfuse-style Trace viewer. A per-user harness system lets you customize the agent's behavior and prompts without touching the codebase.