Joonmo Jeong (i3months)

PACK UP - Developed and Operated an Experience Booking Platform Connecting Travelers and Local Hosts

• packup.asia
• Owned the entire process from planning to development, deployment, and operation - in service after launching on Google Play and the App Store.
• System Composition
• React Native app, React admin, Spring Boot backend.
• Five servers split by role - core, payment, chat, admin, and batch.
• Integrated PayLetter, KakaoPay, and KG Inicis payment gateways (payment isolated in its own server).
• Built on GCP - Cloud Run, Cloud SQL, GCS, Firebase Hosting, and Cloudflare DNS.
• Infrastructure & Operations
• Protected traffic with Cloud Armor - per-IP rate limiting, SQL injection and XSS blocking.
• Isolated batch work in a dedicated server - pinned to a single instance to prevent duplicate runs, with execution history recorded automatically.
• Handled cold starts with Cloud Run min-instance settings.
• Set up Sentry error tracking, Cloud Monitoring uptime checks, and budget alerts.
• Consolidated external integrations into one shared infrastructure module - translation, maps, push, and storage/payment clients shared across all five servers.
• Software Architecture
• Shared database and domain module architecture - booking and payment run in a single transaction for consistency, while notifications are dispatched asynchronously after commit.
• Adopted Feature-Sliced Design (FSD) for the React Native frontend.
• Split push delivery by platform - iOS goes straight to APNs to work around React Native constraints, while Android uses FCM multicast.
• Split services into units an AI agent can grasp at once, with per-service context documents.
• AI-Assisted Development
• Built an AI development harness tailored to the project - per-service context documents, a domain glossary, and explicit rules for what is never delegated.
• Automated repetitive work with Claude Code Skills - i18n keys across 7 languages, exception type updates.
• Used Claude Code Hooks to hard-block frequent mistakes such as hardcoded secrets and production database misconfiguration at tool-execution time.
• Ran review-only agents across four angles - concurrency, security, schema, and i18n - with source-write permission removed to separate review from implementation.

Developed STACK-UP - An AI Interview Platform for IT Roles

• GitHub Repository
• Served as development lead and AI server developer - designed the AI pipeline and the software architecture.
• RAG Retrieval System
• Chunked documents recursively by heading, paragraph, line, and word.
• Prefixed each chunk with a document summary and its heading path to preserve context (lightweight Contextual Retrieval).
• Separated embedding prefixes for indexing and search, storing the vectors in pgvector.
• Ran keyword search alongside vector search to match technical terms the vectors miss, fusing rankings with RRF.
• Designed a fallback path so generation continues from the base context when retrieval fails or times out.
• Question Generation & Answer Scoring
• Managed the question pool as breadth × depth × k - topics are opened and weak points probed, ending at the session-wide question cap.
• Separated RAG queries by stage - opening questions from the job role and document summary, follow-ups from the previous question and answer.
• Scored answers on four axes - specificity, logic, structure, and correctness - branching the criteria by question category.
• Verified the correctness axis against evidence retrieved through RAG.
• Integrated STT and extracted speech metrics such as speaking rate and silence for the report.
• Final Feedback & Model Operations
• Staged scoring - per-answer LLM rating, averaging and normalization, then an LLM summary - smoothing score variance.
• Models split by stage - a larger model for analysis, opening questions, and the summary, a lightweight one for follow-ups.
• Temperature split by model tier - 0.2 for analysis and judgment, 0.4 for follow-up questions.
• Spawned an interviewer persona per job role in the session, scoring in parallel against role-specific criteria to derive the overall score.
• AI-Assisted Development
• Ran development as a multi-agent workflow, assigning planning, design, implementation, and testing to dedicated agents.
• Passed each stage’s artifact to the next agent as input - design is settled before implementation starts, and testing closes the loop.
• Built an AI development harness with project-specific context documents and rules that standardize each agent’s role and artifact format.

Embedded Challenge - Autonomous Maze Navigation Robot on STM32

• GitHub Repository
• Practice run (full completion) video
• Built a maze-navigating autonomous robot on STM32F429 and FreeRTOS, combining ultrasonic and infrared sensors.
• Designed an FSM navigation algorithm that detects intersections from lateral-wall distance changes and branches on heading.
• Corrected odometry drift with EKF sensor fusion, navigating on a lateral-wall heading observation in the absence of an IMU.
• Separated sensing and control with four FreeRTOS tasks (sensing, IR, control, debug) under preemptive scheduling and lock-free shared state.
• Encoder-based 90-degree turn calibration and compensation for left/right motor output asymmetry.

Developed UniScope - A Platform for Nationwide University Information

• GitHub Repository
• Served as Tech Lead - designed the software architecture and led the overall development process.
• Kakao Tech Campus Final Presentation - UniScope Platform
• Documented UI components across the project using Storybook to enhance reusability and improve development speed and design consistency.
• Built an E2E testing environment using Playwright and automated actual browser-based UI flows and key business logic.
• Improved page structure and performance to achieve high scores across 4 Lighthouse metrics, and enhanced initial accessibility through meta tag-based SEO optimization.
• Applied Husky at the pre-commit stage to enforce linting rules and built a CI/CD pipeline based on GitHub Actions.
• Introduced Feature Sliced Design (FSD) architecture and established related team guidelines to ensure maintainability and scalability
• Designed a deployment architecture integrating AWS and Vercel, and built a Blue/Green zero-downtime deployment environment using Nginx reverse proxy.

Developed features for the Chemical Information Platform Service

• Migrated data from TIBERO to MariaDB.
• Indexing migrated data and implemented partitioning for statistical data.
• Optimized queries from TIBERO to MariaDB.
• Implemented hierarchical queries and sorting using WITH RECURSIVE and SORT_PATH.
• Refactored high-cost statistical queries, improving performance (873.231ms → 214.245ms).
• Visualized statistical data using ApexChart and implemented favorites and table search features.

Enhanced functionalities of the DBpia service

• Integrated Redis for floating banners and developed APIs to connect the back office with the DBpia service.
• Modified Elasticsearch queries and existing mappings for the unified search feature, restructured the research paper index.
• Analyzed execution plans, reindexed data, and optimized high-cost queries (4481.926ms → 1111.281ms).
• Managed encrypted view schemas and handled encryption/decryption of sensitive information.
• Maintained DBpia service operations - fixed Excel download bugs, managed the PDF download server, and handled long-term inactive users.

Developed DBpia Content Maker (DCM)

• Analyzed legacy source code written in C# and C++ and designed a new web-based system.
• Utilized Git Flow strategy for seamless collaboration, analyzed user requirements and system processes.
• Set up and managed project configurations and operations.
• Configured Spring Security with custom filters and authenticators, implemented LDAP-based AD account login.
• Customized Spring Security authentication exception handling - Implemented account lockout policy.
• Resolved DataSource TLS compatibility issue with SQL Server 2005.
• Fixed incompatibility between the latest Spring Batch version and SQL Server 2005 sequences.
• Established certificates and domains, NGINX-based reverse proxy routing for development and production servers
• Deployed and managed Tomcat on Windows Server, resolved symbolic link-related network drive permission issues
• Configured Tomcat JVM memory pool and implemented redundancy for production and development servers.
• Handled penetration testing issues, including XSS, CSRF, and sensitive data masking.
• Analyzed and optimized SQL Server Linked Server RPC overhead using OPENQUERY.
• Research Paper Metadata Production System Development
• Developed PDF splitting system (PDFBox, PDF.js) - Handled logical/physical page differentiation
• Refactored a legacy C++ batch system into Spring Batch, integrating ERP and DCM services to enhance stability and processing speed.
• Developed editor draft saving - auto-saved input every 5 minutes.
• Implemented an email-based research paper author search feature using Elasticsearch.
• Efficiency Improvements & Service Optimization
• Revamped the research paper production system, reducing metadata processing time (30 min → 15 min for 50 papers).
• Optimized batch processing, cutting publication time (3 days → 1 day).

Developed the ASD Screening AI Integrated Platform System

• Implemented conditional branching surveys using SurveyJS.
• Transmitted video and audio data via WebSocket for real-time communication with the AI inference server.
• Visualized inference results in real-time using ApexCharts and D3.js.
• Set up system execution environment and deployed images using Docker.
• Developed JWT authentication and CRUD functionality for participants and test results using FastAPI.
• Built and developed the frontend using Vue.

Enhanced functionalities of the ETRI School website

• Unified non-registered student and faculty data into a single table.
• Implemented bulletin board pagination and step-by-step registration using Vue Quasar.
• Developed a Spring Boot and JPA-based back-office system and integrated with the ETRI School service.
• Deployed and managed the system on ETRI's internal servers using Docker.

Developed the Drone Mission Data Management System

• Developed batch business logic for drone data storage.
• Traversed directories using DFS and stored image metadata.
• Detected changes at the project level and updated only modified data.
• Used AtomicBoolean to ensure only one scheduler runs at a time.
• Handled scheduler tasks asynchronously with CompletableFuture.
• Conducted performance benchmarking tests considering JVM warm-up.
• Visualized image data on a map using React.
• Deployed Frontend, Backend, and Database as a unified system using docker-compose.

Enhanced functionalities of the National Supercomputing Center website

• Redesigned the main page and developed the back-office system.
• Added an email verification step for user registration, including security measures and expiration settings for verification codes.
• Visualized supercomputer usage statistics using D3.js and optimized queries (6376.21ms → 430.71ms).
• Implemented a WebSocket-based broadcast feature for connected users.

• Added eziwiki to the Awesome Static Generators list
• Contributor
• https://github.com/myles/awesome-static-generators/pull/221
• Github Stars:

• A modern, lightweight wiki and documentation site generator built with Next.js (November 2025 - present)
• Combines Obsidian's linking model, Notion's UI/UX, and the deployment simplicity of a static site
• Graph view for document links, with tab and history navigation
• Published on npm - npx create-eziwiki
• Lighthouse - Performance 99 / Accessibility 100 / Best Practices 100 / SEO 100
• Owner & Maintainer
• Next.js with TypeScript
• https://github.com/i3months/eziwiki
• https://eziwiki.vercel.app/
• Github Stars:
• Codacy :

5th ETRI Human-Understanding AI Paper Competition

• Developed a model predicting sleep and well-being indicators from lifelog data.
• Paper submitted to ICTC 2026 (under review).

Chungnam National University Algorithm Competition – DevDay

• University-wide algorithm competition held every spring and fall.
• Bronze Prize in June 2026, November 2025, June 2025, and June 2022 / Encouragement Prize in November 2021.

ABC Bootcamp: Data-Driven Course

• Developed "D-Village" a survival-based community building platform for small groups using React and FastAPI.

Chungnam National University Generative AI Challenge

• Developed "PPTree" an automated lecture material generation tool using LangChain.

Kakao Tech Campus 2nd Stage Outstanding Cookies Selection

• Completed the 2nd stage with the highest score in the Frontend track.

11th NTIS Information Utilization Competition

• Developed "NTIS STUDIO" a scientific document editor using Vue and FastAPI.

K-Digital Challenge: 2023 MyData Idea Competition

• Developed "Trippy" a personalized travel app using Flutter.

2023 Environmental Data Utilization and Analysis Competition

• Developed "CEAP" a platform for analyzing company-specific carbon emissions using greenhouse gas data.

Chungnam National University Junior Creative Works Competition

• Developed a refrigerator management service using deep learning-based image recognition.

Quality-Aware Facial Mesh Filtering for Robust Contactless Head-Pose Assessment

• Authors: Minseok Park, Joonmo Jeong
• Accepted · Poster presentation anticipated (2026.11.21)

Structure over Scale: A Multi-Axis Ensemble for Small-Sample Multimodal Lifelog Prediction

• Authors: Joonmo Jeong, Yoonjae Kim, Minsu Kim, Prof. Jong-Ryul Lee (corresponding author)
• Under review · Poster presentation anticipated (2026.10.15)

Environment-Conditioned Hammering-Precursor Monitoring for Reliable Embedded Systems

• Authors: Minyong Jeong, Joonmo Jeong, Woojin An, Seohyeon Cho, Seungwoo Jeong, Prof. Venkatesan Muthukumar (corresponding author)
• Presented at the conference (2026.06.24)

Chungnam National University

Chungnam National University Deep Learning SC Lab - Undergraduate Researcher

2026 Kkumdori Scholarship Recipient

Google AI Professional Certificate

Chungnam National University Practical Coding Course Tutor

University of Nevada, Las Vegas (UNLV) - Visiting Scholar

Seoul National University Next-Generation Semiconductor Innovation Convergence College - Undergraduate Research Intern

KakaoTechCampus 3rd Cohort - Frontend

AI Career School Startup Hackathon L:AUNCH Completion

Chungnam National University 2025 SW-IT Contest Organizer

• Baekjoon Online Judge (BOJ)
• solved.ac
• Codeforces
• i3months-web-shell

AWS Certified Solutions Architect – Associate

TOPCIT Regular Assessment

TOEIC Speaking

43rd Advanced Data Analytics Semi-Professional (ADsP)

54th Structured Query Language Developer (SQLD)