Background

Experience

Ten years of building for the phone in your pocket — the teams I've shipped with and the tools I reach for most.

Career

Where I've worked

Lead Mobile Engineer
2022 — Present
Nara Fintech
- Rebuilt the flagship banking app in SwiftUI and Jetpack Compose, dropping cold-start time from 3.1s to 0.9s.
- Set up the App Store and Play Store release trains with Fastlane, taking deploys from a two-day ritual to a one-click nightly.
- Mentored four engineers and introduced snapshot testing that caught UI regressions before they reached TestFlight.
iOS Engineer
2019 — 2022
Loop Studio
- Owned a social video app from 40k to 900k monthly users, keeping the crash-free rate above 99.8%.
- Wrote the offline-first sync layer in Swift with a Core Data + CloudKit backing store.
Android Developer
2016 — 2019
Bitfield Mobile
- Migrated a 200k-line Java codebase to Kotlin, cutting the average build time by 35%.
- Shipped the first Jetpack Compose screens the team ever ran in production.

Toolbox

SwiftSwiftUIKotlinJetpack ComposeReact NativeFlutterCombineCore DataFirebaseFastlane

Also

B.S. in Computer Science — Korea University, 2016. Apple Developer Academy alumnus, 2018.

Two apps featured by Apple as "App of the Day." Speaker on SwiftUI performance at let's swift, 2023.

Reach out and I'll be glad to share more detail and references.