Особисті дані приховані

Andrey Karpenko
Lead/Senior React Native Developer
Kyiv, Ukraine | [відкрити контакти](див. вище в блоці «контактна інформація») | [відкрити контакти](див. вище в блоці «контактна інформація») | LinkedIn | t.me/obsidianuser92
SUMMARY
Senior React Native and Mobile Engineer with 8+ years of experience delivering production iOS and Android
applications across healthcare, fintech, IoT, safety, sports, and travel. Owns products from architecture and
requirements through store release, with strong expertise in offline-first systems, real-time data, background
services, native integrations, performance, and security. Led mobile teams of up to five engineers while remaining
hands-on in development, reviews, planning, and production support.
TECH SKILLS
Mobile: React Native, React Native CLI, Expo, EAS Build, EAS Update, Hermes
Architecture: React Native New Architecture, JSI, Fabric, TurboModules, Native Modules, React Native Bridge
State & Offline: Redux Toolkit, Redux-Saga, Context API, useReducer, WatermelonDB, SQLite, PowerSync
Data & APIs: REST, GraphQL, Apollo Client, Axios, WebSockets, Socket.io, PostgreSQL, Kysely
UI & Navigation: React, TypeScript, JavaScript, React Navigation, TamagUI, Material UI, ShadCN
Native: Swift, Kotlin, Objective-C, Java, Face ID, Touch ID, BiometricPrompt, Keychain
Location & Media: Google Maps, OpenStreetMap, GPS, Background Geolocation, Headless JS, FFmpeg
Cloud & Services: Firebase, FCM, Realtime Database, Cloud Functions, Twilio, Okta, Datadog, Sentry
Testing & Quality: Jest, React Native Testing Library, Appium, Detox, WebdriverIO, ESLint, Prettier
CI/CD & Monitoring: GitHub Actions, Fastlane, TestFlight, App Store Connect, Google Play, Crashlytics
SELECTED PRODUCTS
Phoenix | Trusted Boaters
Trade.com | Hero Social
Hero Markets | Flats or Spikes
RAKBANK | HostelPass
EXPERIENCE
Senior Mobile Engineer | Accompany Health (Phoenix Healthcare App) Nov 2025 – Present
Led mobile delivery for Phoenix, a US home-care app for clinical teams and patient documentation.
Owned 80% of mobile functionality and deliver features independently from requirements to production.
Architected the React Native CLI app with TamagUI, React Navigation, and Context/useReducer.
Built Okta authentication with PIN, Face ID, Keychain storage, and 24-hour re-authentication.
Implemented offline-first sync across SQLite, Kysely, PostgreSQL, and PowerSync.
Delivered visits, patient history, labs, consent signing, questionnaires, vitals, and referrals.
Added role-based access, insurance and medication photos, Twilio calls, Maps, and Firebase push.
Built iOS and Android background tracking with battery-aware local batching and synchronization.
Optimized rendering and JS thread updates for smoother use on lower-end Android devices.
Automated Jest/Appium testing and Fastlane/GitHub Actions releases issued 2–4 times monthly.
Senior React Native Developer | Eddson (Trusted Boaters of America) Nov 2025 – May 2026
Built a boating safety platform from requirements to mobile store release and web deployment.
Held full responsibility for the React Native app and rescue portal from architecture to release.
Delivered Float Plans, voyage launch, five-minute GPS tracking, incident reports, and SOS.
Created a rescue portal with live vessel maps, active voyages, SOS queues, and user management.
Stored offline coordinates in WatermelonDB/SQLite and synchronized them chronologically.
Prevented lost or duplicate points through unique IDs and idempotent backend processing.
Built iOS background geolocation and Android foreground services with Headless JS.
Improved route accuracy by filtering weak GPS fixes and tuning tracking thresholds.
Set up signing, store assets, first moderation, Fastlane automation, and app publishing.

Senior React Native Developer | Group 107 (Trade PLUS, Cookz) Sep 2021 – Feb 2025
Owned core mobile delivery for five white-label trading apps serving regulated international markets.
Built shared platform capabilities for brands with up to 1,000 active users from one monorepository.
Delivered Cookz from initial architecture to App Store and Google Play release before joining Trade PLUS.
Architected five React Native apps with a shared Core module, feature flags, and reusable business logic.
Built OAuth, biometrics, session recovery, token refresh, KYC, onboarding, and document workflows.
Delivered watchlists, asset search, charts, portfolios, order history, push, and real-time market data.
Implemented Redux Toolkit, Redux-Saga, REST APIs, WebSockets, Victory Charts, and React Navigation.
Added exponential-backoff reconnects and restored WebSocket subscriptions after network interruptions.
Optimized Redux, FlatList, batching, and memoization to keep live quotes smooth on weaker Android devices.
Extended Swift and Kotlin integrations for biometrics, links, files, PDFs, SDKs, and React Native Bridge.
Hardened HTTPS flows with in-memory access tokens, centralized 401 handling, and SSL expiry validation.
Built Cookz video feeds and an FFmpeg editor with trimming, merging, audio, compression, and prefetching.

Lead React Native Developer | Svitla Systems (FlatsOrSpikes) Feb 2021 – Sep 2021
Led greenfield delivery of a US athletics platform for teams, athletes, and event organizers.
Directed mobile architecture and coordinated three React Native developers through release.
Structured modules for teams, athletes, events, meets, statistics, messaging, and profiles.
Added NTP-based timestamps with timezone, daylight-saving, and offline fallback handling.
Rendered thousands of chart points through aggregation, preprocessing, and memoization.
Maintained over 99% crash-free use and resolved critical production defects within one day.
Cut release preparation from 1–2 hours to 15–20 minutes through Fastlane and GitHub Actions.
Led planning, technical risk assessment, code reviews, and alignment with QA and Product Owner.

Lead React Native Developer | CHI Software (HealthTech and IoT) Mar 2020 – Feb 2021
Led two mobile products while remaining hands-on across architecture, development, and releases.
Coordinated three React Native developers within cross-functional teams of 8–10 specialists.
Built nutrition, workout, progress, statistics, activity feed, profile, and social features.
Implemented GraphQL queries, mutations, pagination, caching, normalization, and optimistic updates.
Architected a thermostat app with React Native, Firebase Realtime Database, Cloud Functions, and REST.
Enabled direct local HTTP control with automatic fallback to the cloud API when devices failed.
Synchronized schedules and device state through Firebase using Last Write Wins resolution.
Added FCM alerts and deep links for device failures, status changes, and configuration screens.
Led task allocation, mentoring, estimates, sprint planning, technical decisions, and client demos.
Automated testing, signing, and store delivery through GitHub Actions and Fastlane.
Maintained a two-week production release cycle with QA, regression testing, and monitoring.

Web/Mobile Software Developer | SmartIT (Banking, Travel, Social) Oct 2017 – Mar 2020
Progressed from Junior Full Stack Developer to React Native engineer and mobile technical lead.
Delivered social, travel, and UAE banking products across web, backend, and mobile platforms.
Built React, Node.js, Express, MongoDB, and Socket.io matching and real-time messaging.
Developed HostelPass search, bookings, passes, Stripe payments, maps, geolocation, and push flows.
Built Digital 2.0 account, transaction, transfer, profile, biometric, and notification features.
Integrated a secure native banking SDK through React Native Native Modules for a Java backend.
Coordinated 4–5 developers across planning, reviews, onboarding, architecture, QA, and client sync.
Supported tens of thousands of users with releases every 2–3 weeks and over 99% crash-free use.
Improved selected banking screen load times by 25–30% and reduced post-release defects

EDUCATION
Bachelor’s degree, Computer and Information Sciences, Dnipro National University of Railway Transport

LANGUAGES
English – C1, Ukrainian – Native