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Yongjun Lee (이용준)

iOS Engineer | Swift & Kotlin | Experimentation & Mobile Infrastructure

stareta1202@gmail.com · +82 10 2562 9881

iOS engineer with 5+ years at Binance, KakaoHealthcare and KILO; built Mealligram from inception (2M+ users). Ships native iOS and Android features in Swift and Kotlin, alongside React-based KYC functionality. Experienced in A/B test implementation, regional compliance, mobile architecture and release infrastructure.

Technical Skills

  • Mobile & architecture: Swift, UIKit, Kotlin, iOS, Android, proprietary UI design systems, modular architecture, unidirectional data flow
  • Experimentation & delivery: A/B test implementation, region-specific compliance features, GitHub Actions, GitLab CI/CD, Docker, Tuist
  • Web & backend: React, JavaScript, Python, NestJS, server-side Swift, WebView–native bridges

Education

M.S. in Artificial Intelligence, Yonsei University (in progress) | Mar 2025 – Present

B.S. in Mechanical Engineering, Korea University | Mar 2016 – Feb 2021

Work Experience

Binance

Jan 2025 – Present

Software Engineer (iOS & Full-Stack)

  • Shipped an iOS app refresh and UI components within Binance's proprietary widget design system, supporting layouts in 30+ languages.
  • Developed native iOS and Android features in Swift and Kotlin, alongside React-based web functionality for KYC verification.
  • Implemented A/B test variations and region-specific application behavior to accommodate differing compliance requirements across markets.
  • Owned five core iOS dependency modules and developed Python APIs to automate integration and CI/CD workflows.
  • Built WebView–native bridges connecting iOS, Android and JavaScript components for cross-platform functionality.

KakaoHealthcare

Oct 2023 – Jan 2025

iOS Developer

  • Built a CI/CD pipeline for mental-healthcare iOS services using GitHub Actions, GitLab CI/CD, Docker and Swift, reducing deployment time by 50%.
  • Coordinated designers, product managers and partners as Technical Project Manager, improving ticket-based delivery efficiency by 20%.
  • Consolidated 90+ hospital-specific repositories into a Tuist project with approximately 100 targets, simplifying code management.

KILO

Aug 2020 – Feb 2021; Jun 2022 – Jul 2023

Founding Member / Software Engineer

  • Built Mealligram from inception as a founding engineer; the healthcare app reached more than 2 million users.
  • Led iOS, Android and machine-learning development, introducing unidirectional data flow for cross-platform consistency.
  • Modularized the app architecture and introduced CI/CD to improve testability and streamline build, test and deployment workflows.

JeongYookGak

Feb 2021 – Apr 2022

Lead Software Engineer (iOS & Backend)

  • Developed commerce and delivery iOS apps, including a declarative UIKit framework that reduced code redundancy by 18%.
  • Standardized iOS contribution and code-review practices within a unidirectional architecture.
  • Designed custom hardware and software for a patented IoT electronic scale supporting digitized manufacturing operations.
  • Built in-house back-office systems using server-side Swift and NestJS, reducing facility expenses by 24%.

Languages

Korean (native) | English (fluent)