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Hi, I’m Junmin Lee, a product-minded full-stack engineer who ships end-to-end products across mobile, backend, and web. I thrive on turning ambiguous problems into shipped increments through thoughtful architecture, API design, UI, and native integrations, with a strong emphasis on AI-native workflows and production-quality prompts. I enjoy working in small autonomous teams, value async-first collaboration, and frequently use coding agents like Claude and Claude Code to accelerate development. I’m based in Suwon, South Korea, and open to remote roles with overlap in CET mornings.…Hi, I’m Junmin Lee, a product-minded full-stack engineer who ships end-to-end products across mobile, backend, and web. I thrive on turning ambiguous problems into shipped increments through thoughtful architecture, API design, UI, and native integrations, with a strong emphasis on AI-native workflows and production-quality prompts. I enjoy working in small autonomous teams, value async-first collaboration, and frequently use coding agents like Claude and Claude Code to accelerate development. I’m based in Suwon, South Korea, and open to remote roles with overlap in CET mornings.

Junmin Lee

App Developer, Full Stack Developer, Back-End Developer, +2

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Hi, I’m Junmin Lee, a product-minded full-stack engineer who ships end-to-end products across mobile, backend, and web. I thrive on turning ambiguous problems into shipped increments through thoughtful architecture, API design, UI, and native integrations, with a strong emphasis on AI-native workflows and production-quality prompts. I enjoy working in small autonomous teams, value async-first collaboration, and frequently use coding agents like Claude and Claude Code to accelerate development. I’m based in Suwon, South Korea, and open to remote roles with overlap in CET mornings.…Hi, I’m Junmin Lee, a product-minded full-stack engineer who ships end-to-end products across mobile, backend, and web. I thrive on turning ambiguous problems into shipped increments through thoughtful architecture, API design, UI, and native integrations, with a strong emphasis on AI-native workflows and production-quality prompts. I enjoy working in small autonomous teams, value async-first collaboration, and frequently use coding agents like Claude and Claude Code to accelerate development. I’m based in Suwon, South Korea, and open to remote roles with overlap in CET mornings.

Available to hire

Hi, I’m Junmin Lee, a product-minded full-stack engineer who ships end-to-end products across mobile, backend, and web. I thrive on turning ambiguous problems into shipped increments through thoughtful architecture, API design, UI, and native integrations, with a strong emphasis on AI-native workflows and production-quality prompts.

I enjoy working in small autonomous teams, value async-first collaboration, and frequently use coding agents like Claude and Claude Code to accelerate development. I’m based in Suwon, South Korea, and open to remote roles with overlap in CET mornings.

Skills

Experience Level

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Intermediate

Language

Korean

Fluent

English

Advanced

Work Experience

Flutter Developer at Fida

December 1, 2024 - December 1, 2025

Sole mobile engineer responsible for end-to-end Flutter app development, architecture, UI, native integrations, CI, and store releases for iOS and Android. Implemented client-side validation to prevent cross-account data exposure, serialized token refresh to avoid race conditions, integrated Kakao and Apple social login, PortOne verification, SSE-based real-time results pipeline, and remote-config-driven updates. Set up push notifications and crash logging; contributed to product planning and ongoing maintenance.

Flutter & Node.js Developer at LinkConnection

August 1, 2022 - November 1, 2023

Full product ownership of a healthcare app (hospital booking & physical therapy) — delivered Flutter frontend, Node.js REST API (MVP), and JavaScript admin dashboard from zero to launch. Designed backend structure and MySQL schema; led external vendors and freelancers; contributed to product planning and app policy documentation.

Flutter Developer at Gramium

January 1, 2021 - January 1, 2022

Developed features for a dating/social meetup app using Flutter and Firebase. Implemented real-time data synchronization with Firestore for chat and social features.

Java Backend Developer at RFX Soft

October 1, 2019 - September 1, 2020

Developed backend REST APIs and data-grid interfaces for a smart factory MES platform. Deployed Spring applications on Linux, performed production debugging and log-based troubleshooting, managed MySQL backups and restorations, and built frontend data-grid components using vanilla JavaScript for manufacturing dashboards.

Sole mobile engineer — Flutter Developer at Fida (Startup)

December 1, 2024 - December 1, 2025

Sole mobile engineer owning the full product end-to-end, from architecture and UI to native integrations, CI, and store releases on iOS and Android. Implemented client-side token validation to prevent cross-account data exposure, designed a 2-phase commit pattern for serialized token refresh to avoid race conditions, built a real-time QR-to-result SSE pipeline, created native platform channels for unified permission handling, integrated Kakao + Apple social logins and PortOne (Iamport) for identity verification, and added FCM push support with topic-based segmentation. Participated in product planning and iterative post-release improvements guided by Crashlytics signals.

Flutter & Node.js Developer at LinkConnection (Startup)

August 1, 2022 - November 1, 2023

Owned the full healthcare app product: delivered Flutter frontend, Node.js REST API (MVP), and a JavaScript admin dashboard; designed backend structure and MySQL schema; coordinated with external vendors and freelancers; contributed to policy documentation and wireframes.

Flutter Developer at Gramium (Startup)

January 1, 2021 - January 1, 2022

Developed features for a dating/social meetup application; implemented real-time data synchronization with Firestore for chat and social features.

Java Backend Developer at RFX Soft (MES Domain)

October 1, 2019 - September 1, 2020

Developed backend REST APIs and data-grid interfaces for a Manufacturing Execution System (MES) platform; deployed and maintained Spring applications on Linux servers with production debugging and log-based troubleshooting.