I'm a frontend developer with 3 years of experience who understands problems from the user's perspective and turns business requirements into stable products. I've built experience across diverse environments—from global B2B SaaS booking and website builders to AI content web and kiosk clients, and I've run the kiosks I built at 65-70 offline events in Korea and abroad. Beyond core feature development, I've worked on performance optimization, internationalization, legacy modernization, and Electron application development with integrations for payment modules, printers, and other external systems.
I don't stop at implementing features to spec—I consider the user journey and operational environments together. I balance usability, maintainability, and operational stability, collaborating with planning, design, backend, QA, and operations to propose better technical solutions. I aim to be a frontend developer who raises both product quality and team development efficiency by balancing user needs, business goals, and technology.
EXPERIENCE
2025.08 ~ Present
- Migrated the C# WPF kiosk client to Electron + Next.js (IPC, logging, device auth, JSON per-store settings)
- Built kiosk content (AI photo, tarot, personality tests, kuji, claw machine, AI music, voice LLM chat) for 65-70 events in Korea and abroad
- Rolled out the renewed kiosk to ~150 devices: 30K card payments and 8K coupon uses a year (peak 2,000+ payments/day)
- Added WatchDog, kiosk mode, and auto shutdown; on-site "app closed" calls stopped
- Set up Sentry monitoring with Slack alerts to catch failures like AI polling right away
- Integrated KICC payments (payments, refunds, cardless refunds) and photo, card, and POS receipt printers
- Supported 5 languages and locale-aware date/time formats with next-intl and dayjs
- Built accessible kiosks with Windows TTS and Electron dual screens
- Customized an open-source remote management client and built a back-office for kiosk sales and device status
- Swapped a paid AI music API for open-source ACE-STEP 1.5 Turbo ($0 per request)
- Evaluated Hugging Face models (Z-Image, Qwen-Image, FLUX, WAN, etc.) on a local GPU for on-site use
2023.03 ~ 2024.12
- Built a website builder SaaS (page, multi-level header and footer editors with renderer, useFieldArray dynamic forms)
- Owned the global hospital booking system (booking, cancellation, and refund flows; contributed to growth from ~50 to 1,000+ clients)
- Migrated Redux → SWR and Formik → React-Hook-Form, and split 1,000+ line components
- Cut First Load JS by ~46% (289kB → 155kB) with dynamic import and tree shaking
- Moved CSR pages to SSR/SSG and parallelized API calls with Promise.all/allSettled; initial HTML load -33% (1.79s → 1.2s)
- Applied On-Demand Revalidation and fixed sitemap generation (~5% missing pages recovered)
- Supported 40+ languages and RTL via CSS Logical Properties; automated translation for 40+ languages with GPTs
- Traced next-auth session leaks to a shared axios instance and added an ESLint rule to prevent it
AWARDS
ACTIVITIES
2025.01 ~ 2025.02
DND 12th Team 4 Lead
Joined as Team 4 lead after winning the Hackathon Free Pass Special Award. Led the 'Picki talki' walkie-talkie diary platform from planning to deployment over 8 weeks, with offline final presentation and booth operation in collaboration with Yapp.
2022.02 ~ 2023.01
Hansei University Web Dev Club 'Potato Club' 3rd & 4th Term
Served as frontend developer and treasurer, contributing to club project development and operations.
SKILLS
Front-End
HTML/CSS, JavaScript, TypeScript, React, Next.js, Electron, Styled-Components, Tailwind CSS, Context API, Zustand, Recoil, React-Query, SWR, OpenAPI Generator, Orval, React-Native, Flutter
Deploy
AWS, Vercel
Etc
Figma, Postman, Slack, Notion, Git
LET’S TALK
CONTACT ME
woalswhwh@gmail.com
FOLLOW ME
FrontEnd Developer KoJaem
FrontEnd Developer KoJaem
FrontEnd Developer KoJaem
FrontEnd Developer KoJaem