Kim Soo-min Senior Flutter Developer
Seoul, South Korea • flutterdev@gmail.com • +82 2 555 0142
Profile Summary
- Senior Flutter Developer with 7 years of experience building cross-platform Flutter apps on iOS and Android across consumer fintech, payments, and brokerage surfaces, specializing in Dart 3 architecture, Riverpod state design, and platform channel work.
- Hands-on coverage across Flutter 3.24, Dart 3, Impeller, go_router, Riverpod, Dio, Drift, flutter_test, and integration_test with strong fundamentals in strong Dart fundamentals, widget composition discipline, and native-platform fluency on both iOS and Android.
- Deep expertise in feature-first module layout, typed navigation and API layers, reactive provider composition, and platform-adaptive UI primitives, leveraging methodologies such as Impeller adoption on iOS and Android and offline-first sync through Drift and Isar to drive smooth, native-feeling apps shipped from one Dart codebase to both app stores.
- Engaged collaborator working cross-functionally with Design, Product, Backend, iOS, and Android teams in Agile and continuous-delivery environments, contributing to design-review forums, sprint planning, and architecture discussions with a pragmatic, ownership-first mindset.
- Emerging leader who shares technical excellence and fosters a culture of crash-free sessions and App Store and Play Store readiness through PR reviews and widget docs, while leading Flutter guild sessions and authoring widely used widget and provider templates.
Technical Skills
- Languages & Runtime:
- Dart 3 (sound null safety, records, patterns, sealed classes, extension types), async/await, Streams, Futures, isolates, Swift and Kotlin for platform channels
- Flutter & Toolchain:
- Flutter 3.24/3.22, Impeller renderer, Material 3, Cupertino, flutter_localizations, Flutter Web, Flutter Desktop (macOS, Windows, Linux), Flutter CLI, pub.dev packages
- State & Navigation:
- Riverpod, BLoC/Cubit, Provider, GetX, MobX, Redux, go_router, auto_route, Navigator 2.0, deep linking, state restoration, flutter_hooks
- Data & Networking:
- Dio, http, Retrofit (Dart), graphql_flutter, REST, json_serializable, freezed, built_value, OAuth/OIDC, JWT, Firebase Auth, WebSockets
- Persistence & Storage:
- Drift (SQLite ORM), Isar, Hive, ObjectBox, sqflite, SharedPreferences, flutter_secure_storage, path_provider, offline-first sync
- Native & Platform:
- Method Channels, Event Channels, Dart FFI (C/C++), Pigeon, Swift and Objective-C, Kotlin and Java, custom Flutter plugins, Firebase Cloud Messaging, deep linking, biometrics, BLE
- Testing & Quality:
- flutter_test, Mockito, Mocktail, integration_test, Patrol, golden tests, Flutter DevTools (widget inspector, timeline, memory), Sentry, Firebase Crashlytics
- Release & CI/CD:
- Flutter CLI, build flavors, App Store Connect, Google Play Console, TestFlight, AAB packaging, Fastlane, Codemagic, Bitrise, GitHub Actions
Education
Seoul National
University
B.S. in Computer
Science
Work Experience
Toss
Senior Flutter
Developer
- Drove Flutter feature delivery on the Toss money app serving 22M monthly actives, shipping payments, brokerage, and card flows from one Flutter 3.24 codebase to both iOS and Android across 38 feature modules.
- Owned the Dart layer with sealed classes with freezed, pattern matching for result types, and isolates for heavy parsing, holding sound null-safety coverage at 100% and shipping 120+ typed domain models reused across the consumer and partner surfaces.
- Built the widget tree with Material 3 with Cupertino fallbacks, const widgets for the hot paths, custom RenderObject work for the home dashboard, and platform-adaptive theming across both stores, shipping 90+ custom widgets while holding the per-frame budget at 16ms on Impeller.
- Owned app state with Riverpod with async notifiers, family providers for parameterised reads, and code-generation through riverpod_generator, shipping 180+ providers across the app and cutting unnecessary widget rebuilds by 46%.
- Owned navigation with go_router with typed routes, nested ShellRoute layouts for the tab bar, redirect guards for auth, and state restoration on cold start, wiring 75+ typed routes and 40+ deep links across iOS and Android.
- Built the API and data layer with Dio with Retrofit clients, interceptors for OAuth refresh and retry, json_serializable models, and OIDC sessions backed by flutter_secure_storage, wiring 140+ endpoints and lifting cache hit rate by 42%.
- Shipped local persistence with Drift with Hive caches, typed SQLite schemas, background isolate sync, and flutter_secure_storage for credentials, modeling 32 tables and lifting offline session usage by 28% in flaky network regions.
Coupang
Flutter
Developer
- Drove performance and memory work with Flutter DevTools timeline, const widget audits, ListView.builder for long-scroll views, and image cache tuning, pulling cold start from 2.8s to 1.3s and holding feed scrolling at 60 fps across both platforms.
- Owned native integration with Method Channels with Pigeon, typed Swift and Kotlin bridges for SDK access, and Dart FFI for image processing hot paths, authoring 6 custom Flutter plugins and wiring 3 FFI hot paths into the checkout flow.
- Owned build, release, and distribution with Codemagic with Fastlane, automated TestFlight and Play Console submissions, AAB packaging with R8 shrinking, and 4 build flavors for staging and prod, shipping 55+ store releases across iOS and Android during the tenure.
- Partnered Design, Backend, iOS, and Android on the shared product roadmap, authored 5 Flutter architecture RFCs adopted across the mobile org, and onboarded 4 junior Flutter developers through PR reviews and pair programming.