Frontend Engineer
Frontend Engineer experienced in the entire product lifecycle from inception to growth
Experienced in growing a service from the idea stage to 23k MAU. I have learned how to build stable services by directly experiencing the entire process of planning, development, deployment, and operation.
I prefer deep technical exploration—implementing necessary features directly rather than relying solely on libraries—and understanding principles by diving deep into official documentation. I have experience designing proprietary UI systems and optimizing rendering performance to the limit.
I aim for rational engineering, selecting and applying technologies based on the current business context and "what users truly need," rather than blindly chasing the latest or flashy technologies.
Work Experience
Orca AI Inc.
Co-Founder / Frontend Lead ~Description
A global AI character chat platform. As a Co-Founder and Frontend Lead, I led the entire process of planning, development, and operation.
What did I Do
- [Key Achievements] Achieved 23k MAU and $3,000 monthly revenue, building a highly immersive service with an average session time of 46 minutes (Ranked 57th in Google Play Entertainment / as of Feb '25)
- [Architecture Enhancement] Transitioned to a server-based multi-model to overcome local model limitations and implemented logic to migrate existing Realm data to Firestore without loss. Introduced React Query Persister to improve initial loading speed and establish a server data caching strategy.
- [Cross-Platform Design] Supported Android, iOS, and Web simultaneously with a single codebase based on Expo Router, and integrated Universal Link to provide a seamless user experience across platforms.
- [Rendering Optimization] Prevented frame drops on low-end devices by introducing Flashlist for high view reusability, and proactively adopted React Compiler to reduce code complexity and optimize rendering efficiency.
- [High-Performance Interaction & R&D] Experimented with next-gen interfaces (V2) by implementing iOS 26 Liquid Glass and Shorts-style Swipe UI, and achieved native-level 60fps gesture animations using Reanimated (v4).
- [UX-Centric Monetization] Directly designed Native Ads UI that does not disrupt the chat experience, ensuring seamless ad exposure and layout stability (preventing CLS).
- [Service Stability] Built a precise error tracking environment by integrating Sentry and dSYM, and prevented user churn with a rapid rollback policy when specific Android device issues occurred. Ensured runtime data type safety by introducing Zod.
- [Operational Efficiency] Built CI/CD pipelines based on EAS and GitHub Actions (Android closed track auto-deployment, iOS TestFlight) and established a device compatibility testing process using Samsung Test Lab.
- [Global Expansion] Supported 3 languages (KR/EN/JP) via i18n, driving global user influx, and verified edge computing feasibility by conducting an On-device sLLM PoC using `llama.rn`.
Tech Stack
- React Native
- TypeScript
- Expo
- Flashlist
- Reanimated
- React Query
- Zod
- Firebase
- Sentry
Vault Micro
Frontend Developer ~CameraFi Studio View project details →
Description
A web overlay scoreboard service. Started as a solo developer, I built the frontend architecture and grew it into a core company project.
What did I Do
- [Bundle Size Optimization] Reduced main bundle size by 15% (324KB → 277KB) and improved TTI by establishing Webpack Tree Shaking & Code Splitting strategies and applying Dynamic Import.
- [Security & Auth] Removed external dependencies and enhanced security by directly implementing Cookie Consent and token-based authentication logic instead of relying on libraries.
- [Global Architecture] Designed a flexible structure for design changes by building an i18n system and a Global Theme System combining MUI and Styled-components.
- [Service Enhancement] Implemented app-like installation (A2HS) by introducing Next-PWA and established a subscription lifecycle management process by integrating Paddle payment solution.
Tech Stack
- Next.js
- TypeScript
- Mui
- PWA
- Webpack
- Firebase
- Paddle
Internal Admin Dashboard
Description
An internal service management and statistics dashboard.
What did I Do
- [Large List Optimization] Implemented Intersection Observer-based Infinite Scroll to enable seamless navigation of hundreds of thousands of video lists, benchmarking YouTube UI.
- [Productivity Improvement] Abstracted CRUD logic and Chart.js visualization modules into reusable components, accelerating the development speed of repetitive admin pages.
- [Infrastructure] Built and managed SPA deployment pipelines using Firebase Hosting.
Tech Stack
- React
- TypeScript
- Mui
- Chart.js
- React Query
- Firebase Hosting
Ministry of National Defense
Software Developer ~Web-based Document Viewer
Description
A document viewer development project in a closed network environment with restricted external library access.
What did I Do
- [Large Data Rendering] Implemented seamless scrolling by introducing React Table and Virtualization techniques to prevent rendering delays when processing thousands of rows of Excel data.
- [Architecture Design] Introduced Redux-Saga for asynchronous data processing and applied Atomic Design Pattern to build a component system for maintenance efficiency.
Tech Stack
- React
- TypeScript
- React Table
- Redux-Saga
- Atomic Design
MND Dashboard Page
Description
Maintenance and enhancement project for the dashboard webpage within the Ministry of National Defense intranet.
What did I Do
- [Maintenance] Developed UI components by customizing the Ant Design library and secured system stability through legacy code refactoring.
Tech Stack
- React
- JavaScript
- Ant Design
- styled-components
- Redux
Skills Set
Languages
- TypeScript
- JavaScript (ES6+)
Frontend
- React
- React Native
- Expo (Router, EAS)
- Next.js
- Svelte / SvelteKit
Engineering
- Reanimated (v4)
- Flashlist
- React Compiler
- MMKV
- PWA
- React Query
- Zod
- React Hook Form
DevOps & Tools
- GitHub Actions
- Firebase
- Sentry
- Cloudflare Pages
- Git / GitHub
- Figma
- Vim
Awards & Projects
Seoul Campus Town Selection (Orca AI)
Selected for office space and commercialization funding support from the Seoul Metropolitan Government and universities in recognition of business potential and technical capability.
2021 Woori Bank Hackathon Finalist View project details →
Advanced to the finals by independently planning and developing a fintech app with remittance and biometric authentication features, learning React Native with a rapid learning curve in 5 days.
SvelteKit Portfolio Website View project details →
An edge-enhanced website maximizing performance and user experience using Cloudflare Pages and Svelte 5.
Education
Hanyang University
B.S. in Computer Software Engineering ~Sejong Science High School
~Archives
Election News Aggregator View project details →
A project for Hanyang University Software Studio 2. As a team leader, I led the entire process of planning, design, and development, experiencing Serverless architecture.