About Me
I have worked on Spring Boot and PostgreSQL backends and Python-based AI integrations. In the AI Trading Coach capstone, I was PM and worked on the order-decision backend, connecting user rules, model signals and mock orders. Model signals can exclude candidates, while rule-based code determines order size and final approval.
I maintain a fork of comic-translate, where I worked on local OCR and translation runtimes, the OCR request path and caching for repeated work. In a stock trading simulation, I built Spring Boot flows for orders, wallets and holdings.
I self-host Kavita, Jellyfin and personal projects on a NAS and OCI. I check changes with tests and run records, and record the input and comparison conditions alongside performance results.
Skills
AI / LLM
- RAG: PostgreSQL and pgvector storage, access-aware retrieval, citation and number checks
- Local OCR and LLM: connected PaddleOCR-VL, HunyuanOCR and Gemma runtimes through Docker and llama.cpp, with stage caching
- Team AI server: wrote Docker, GPU setup and switching scripts for vLLM, Ollama and GPT-SoVITS
Back-end
- Primary: Java, Kotlin, Spring Boot, Python, FastAPI, PostgreSQL
- REST APIs, SQL, transactions, locking, database constraints, error and state handling
- Also used: MySQL, Redis, WebSocket/STOMP
Infrastructure
- Docker, Linux, GitHub Actions, Nginx, personal NAS and OCI services
- Windows setup and run automation, pytest and JUnit, reproducible benchmarks
Others
- C++ (including C++20): used mainly in university coursework and coding test practice
- Kotlin Android, Jetpack Compose and Room project experience
- Git, GitHub pull requests, technical documentation and cross-project API contracts
Experience
document-translate-myfix
Personal open-source fork · local OCR and translation runtimes
Apr 2026 – Present
GitHub
- Implemented Docker start, stop and resource-release paths so OCR and translation models could use the GPU in turn.
- Changed chat and speech APIs and the vLLM, Ollama and GPT-SoVITS setup and switching scripts.
- GPU memory limits required choosing either vLLM or Ollama at a time. The final demo used the Ollama path.
Personal NAS and OCI Self-Hosting
Personal infrastructure operations
Winter 2022 – Present
- Self-hosted a Kavita library, Jellyfin media service and personal projects with Docker on a NAS and OCI Linux VM.
- Page turns in remote Kavita reading were delayed, so I set up image and PDF caching and next-page preloading. When preloading failed due to a certificate-name mismatch, I aligned TLS SNI and HTTP Host and checked response, cache and queue records.
- Tested XPEnology on Proxmox, then removed the Proxmox layer. XPEnology is now the main NAS, with services running in Docker.
Projects
AI Trading Coach with User-Defined Risk Rules
Three-person capstone · PM / Decision Platform
May 2026 – Oct 2026
GitHub
- Requiring both the rules and model to say BUY left over half of offline sessions without a candidate. I changed the flow to rule-proposed candidates with a model SELL veto.
- Compared six combinations on the same 31 stocks and 5,362 sessions: no-candidate rate fell from 51.8% to 1.4%. I implemented the rule and added regression tests.
- Mock-order tests covered submission, fills, balance updates and duplicate prevention after user and safety checks.
- Separated financial sources, revisions, chunks and embeddings in PostgreSQL, with public/private retrieval and citation checks.
- Teammates owned LSTM training, the Return Engine and dashboard UX.
Document and Image Translation Pipeline
Personal open-source maintenance fork
Apr 2026 – Present
GitHub
- Added local HunyuanOCR, PaddleOCR-VL and Gemma paths to comic-translate.
- Direct model requests cut OCR wall time from 60.2 to 8.3 seconds on the same six Japanese pages and 73 text regions; the final normalized OCR results matched.
- Stage caching reuses matching input, model and settings. A two-page first run plus identical rerun took 279.9 seconds without caching and 156.0 seconds with it.
- Built Spring Boot flows for orders, wallets, holdings and trade history. Price requests run outside DB transactions; balance and holding changes use locking and transactions.
- Cached prices with Redis and delivered them through WebSocket. I integrated a FastAPI AI server and deployment setup; a teammate owned the interface and design.
KB AnsimVoice and Money Rules
Three-person contest prototype · Agent / TTS
Jul 2026 – Aug 2026
Public GitHub
- Rechecked the amount, recipient and account in an AI-drafted transfer against the user’s utterance and server data. Mismatches are not passed to the transfer flow.
- Rule-based code handles transfer decisions and one-time approval. I worked on the constrained agent, input checks and TTS, WebSocket and Docker integration.
- Built a Java, Spring Boot and PostgreSQL course project for supplier, order, delivery, inventory and carbon data.
- Kept order, delivery and inventory changes in one transaction, with database constraints and error handling to prevent inconsistent updates.
OliveME Personal Color Android App
Two-person team · Android architecture / data / integration
May 2026 – Jun 2026
Team GitHub
- Built Android screens and storage flows with Kotlin, Jetpack Compose and Room, and connected AI and map APIs.
- Kept saved diagnoses and local guidance available when an external API or backend fails. A teammate shared the screen design work.
- Built session authentication, product and comment flows, search and account pages with Express, EJS and MySQL in a two-person course project.
- Connected Verilog state machines, clock division and transmit/receive modules to buttons, LEDs, seven-segment displays and a buzzer on an FPGA board.
- Combined visitor, transport facility and accident data around 50 Busan attractions, then published statistical analysis, maps, a notebook and a report.
External Activities
KEEPER Security Club
Member
Mar 2025 – Aug 2026
- Joined the web vulnerability study from Mar to Jul 2025.
APPTIVE
Member
Mar 2026 – Sep 2026
Kakao Tech Campus
Agentic AI · In progress
May – Nov 20, 2026 (expected)
- Completion and project links will be added after verification.
Education
Pusan National University
Computer Science and Engineering
Expected graduation: Feb 2027