I build production mobile applications with a strong focus on architecture, user experience, performance, and difficult integrations.

I've been working professionally with Flutter since 2022, and currently own mobile engineering at BILLZ, where I've helped grow the mobile POS product from a secondary application into a stable, independently usable product with 20+ modules and ~4K daily active users.

📱 Flutter & Dart
🏗️ Architecture & Refactoring
🔌 Native SDK & Hardware Integrations
⚡ Performance Optimization
🧪 Unit & Widget Testing
🚀 CI/CD & Release Engineering
📴 Offline-First Applications
🎨 Complex UI/UX

I especially enjoy problems where the straightforward solution isn't good enough.

That includes building native Flutter plugins, integrating hardware and payment SDKs, refactoring growing codebases, optimizing complex workflows, and designing better experiences for real users.

Some measurable results from my work:

Mobile Engineer · 2022 – Present

As the sole dedicated mobile engineer, I work across the full product lifecycle:

• Architecture and large-scale refactoring
• Feature development and complex business logic
• Performance optimization
• Hardware and native SDK integrations
• Testing and regression protection
• CI/CD and app releases
• Production debugging and observability
• UX improvements and product decisions

• ESC/POS & TSPL thermal printing
• Bluetooth / USB / Ethernet hardware integrations
• NFC / SoftPOS payment integrations
• Fiscalization integrations
• Custom printable label designer
• Offline-first data workflows
• Native Flutter platform plugins
• Automated Android/iOS CI/CD
• Interactive onboarding
• Production analytics and crash monitoring

A Flutter plugin for XPrinter thermal receipt printers with native SDK integration.

Supports:

• Android
• iOS
• Windows
• ESC/POS commands
• Bluetooth / USB / Ethernet
• 58 / 72 / 80 mm paper sizes
• Cyrillic text
• Image dithering

Used in production by BILLZ.

→ View repository

Flutter plugin for XPrinter TSPL printer functionality.

Used in production by BILLZ.

→ View repository

Built from scratch and later expanded from mobile to Android, iOS, and Web.

Worked on clinic registration, appointments, medical records, test results, referrals, vaccinations, prescriptions, and complex appointment business logic.

Built the complete Flutter mobile application for both workers and companies, including role-based flows, vacancies, applications, chat, and notifications.

Built a Korean vocabulary learning product with 50,000+ words, widgets, native iOS capabilities, local-first synchronization, Supabase, and subscriptions.

Built an AI-assisted product-label analysis application using on-device image-to-text processing and Gemini/GPT models.

Clean Architecture · Feature-Based Architecture · Layered Architecture · MVVM · Repository Pattern · Dependency Injection

BLoC / Cubit · Provider · GetX

REST · WebSockets · Dio · Retrofit

Isar · Hive · SQLite · Drift · Secure Storage

Firebase · Supabase

Unit Testing · Widget Testing · Regression Testing

GitHub Actions · TestFlight · Google Play · Shorebird

Native SDKs · Platform Plugins · ESC/POS · TSPL

NFC / SoftPOS · Payments · RevenueCat

Maps · Video · Push Notifications

AppMetrica · Mixpanel · PostHog

Firebase Crashlytics · Sentry · Firebase Remote Config

I've worked with teams and clients across 20+ countries, across different time zones, cultures, product requirements, and development workflows.

Products I've worked on include:

POS · Healthcare · AI · Recruitment · Financial Education · Travel · Sports · Media · E-commerce · Consumer Apps

I write about Flutter and mobile engineering, including:

• Architecture
• State management
• Firebase
• Location services
• Native integrations
• Production development

→ Read my articles on Medium

Build for the user. Design for change. Ship for production.