Available to hire
I’m a Senior Mobile Engineer and Technical Lead with 8+ years of experience shipping consumer apps, with deep focus on end-to-end delivery—not just screens. I’ve built and evolved mobile products using React Native (since 2018, coding since 2015), taking ownership from product scope and architecture through iOS/Android implementations, CI/CD, and store releases.
I’ve led major rewrites and brownfield-to-shared migrations, including a native-to-React Native CLI consolidation for Monster and an Expo/React Native platform for UNLOQ (Vouch) that reached #1 in the Entertainment category in Poland. I also bring strong native expertise (Swift/SwiftUI/Objective-C and Kotlin/Java) and a practical approach to reliability on regulated and high-impact flows, using testing (Jest/Detox/Appium), analytics, and production-grade release pipelines.
Skills
Experience Level
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Intermediate
Intermediate
Language
English
Fluent
Polish
Fluent
Work Experience
Owned platform end to end (Expo / React Native app) at UNLOQ (Vouch) / Vouch
April 1, 2026 - July 31, 2026Owned the platform end-to-end: Expo/React Native mobile app with Firebase (Auth, Firestore, Cloud Functions) and a Next.js admin panel. Built DevEx and release path with EAS Build/EAS Update (OTA), force-update gates, and GitHub Actions for automatic backend deployments. Shipped trading challenge and real-time leaderboards; implemented user verification, notification targeting, deep linking, WebView campaign flows, and analytics for major live campaigns.
Mobile Team Lead at ITI (International Team for Implantology)
September 1, 2025 - March 31, 2026Led pre-sales scoping and estimation and then delivery of the ITI app across roadmap, change requests, beta, and store release. Designed integrations including SSO/MS Dynamics membership, WordPress and Liferay CMS, Docebo LMS, Stripe checkout, and an AI chatbot. Supported product features such as AI content feed, community forum, Study Club, e-learning, and e-commerce.
Mobile Lead / Mobile Team Lead (Rewrite) at Monster
November 1, 2024 - August 31, 2025Led a full rewrite of Monster’s flagship iOS and Android job search apps into one React Native CLI codebase at feature parity. Mapped legacy native screens to shared RN flows, preserved persisted user data across cutover, and kept native shared modules. Consolidated native release trains into a single Fastlane pipeline shipping from one RN codebase via App Store/Google Play, with Firebase Crashlytics/Messaging and Jest/Detox on core job-search flows.
Senior Mobile Engineer / Mobile Team Lead at nomtek
November 1, 2024 - July 31, 2026Remote product engineering for international client delivery across mobile apps, admin tooling, backend services, and release infrastructure.
Senior Software Engineer at EY
July 1, 2024 - October 31, 2024Built and hardened a React Native learning app for Abu Dhabi’s Department of Government Enablement. Refactored legacy screens into reusable architecture, added Jest/Detox on critical learning flows, and improved authentication, secure storage, and API communication in collaboration with stakeholders.
Senior Mobile Engineer at JPMorgan Chase & Co. (Chase UK)
September 1, 2023 - May 31, 2024Shipped React Native payment features in a payments squad for Chase UK’s app-only retail bank, integrating GraphQL payment data. Added Appium, Jest, and Detox coverage for regulated payment flows used in production; implemented reliable production-grade mobile behavior.
Mobile Team Lead at CSHARK (Fixvi)
January 1, 2023 - July 31, 2023Led mobile delivery for Fixvi: pre-sales estimation and team leadership from greenfield to store releases. Defined architecture and implemented shared patterns across the iOS/Android codebase including native modules and testing strategy.
Trainer (React Native) at CSHARK
December 1, 2022 - December 31, 2022Authored and delivered a 2-week React Native program for engineers, covering setup through native modules, navigation, and store deployment via live coding from zero to a working app.
Senior Mobile Developer at Blaise Transit
November 1, 2021 - January 31, 2023Delivered passenger and driver apps for on-demand transit operations. Migrated components to TypeScript, implemented Mapbox-based navigation and OSRM routing on iOS/Android, and improved routing logic to prevent undesirable maneuvers.
Software Engineer / Mobile Team Lead at CSHARK
November 1, 2021 - July 31, 2023Estimated mobile builds in pre-sales, then led a 4-person team from greenfield through App Store/Google Play delivery. Owned architecture decisions and native module delivery across Swift and Kotlin. Established an implementation stack and quality practices using React Navigation Native Stack, Expo Modules, React Query, Valtio, forms (Formik/Yup), i18next, Sentry, and Jest/Detox.
Senior React Native Developer at Orange (Orange Flex)
August 1, 2021 - November 30, 2021Shipped the Eco GB transfer feature in Orange Flex, added ESLint locale-path suggestions across bundles, and expanded Jest/Detox coverage to speed development workflow.
Mobile Developer at Entia Ltd
May 1, 2021 - July 31, 2021Rebuilt accessibility features for disabled and elderly users on a at-home hemoglobin test app and extracted shared components to enable new post-MVP flows without duplicating screens.
iOS Developer at Booksy (business app)
February 1, 2021 - June 30, 2021Built SwiftUI + Combine views for the Booksy business app and ran a brownfield proof of concept enabling two-way state between SwiftUI and React Native via RN components embedded inside native views.
Mobile Developer at Versum (powered by Booksy)
August 1, 2020 - February 28, 2021Shipped features for V ersum (businesses) and Moment (customer bookings) and kept mobile behavior in sync with the web platform. Implemented subscriptions and payments, Detox E2E tests, and created a Storybook component library for the mobile team.
Mobile Engineer at Docplanner Group (ZnanyLekarz)
January 1, 2020 - August 31, 2020Led a brownfield transition from native apps to hybrid delivery across Android and iOS, coordinating React Native inside Groovy Android and Objective-C iOS with Gradle upgrades and native bugfixes. Built real-time chat as a separate React Native module and migrated users to the chat-enabled build.
Frontend Developer at Nextapps
February 1, 2019 - December 31, 2019Worked on frontend development including React Native/related delivery for products during the freelancing period.
Lead Mobile Developer at Jugendapp
January 1, 2019 - December 31, 2019Led mobile delivery including city maps, events, chat, offline sync, and an AR game.
Software Engineer at Earnr
January 1, 2019 - December 31, 2019Built mobile app features including in-app purchases and production integrations with Plaid, Intercom, and HMRC.
Software Engineer (contract engagements) at Various clients (React Native contractor)
January 1, 2019 - July 31, 2023Selected React Native client work as an independent contractor including fintech and Swiss civic applications with features across payments/integrations and offline-capable app experiences.
React Native Freelancer at Self-employed / Remote
May 1, 2018 - February 28, 2019Freelance React Native development work delivered remotely, contributing across app architecture, UI, and testing for multiple engagements.
Education
Computer Science at Nicolaus Copernicus University in Toruń
January 1, 2016 - January 1, 2020Qualifications
iOS Development Training - Sages
March 1, 2021 - August 29, 2026React Native: Advanced Concepts - Udemy
July 1, 2020 - August 29, 2026Industry Experience
Software & Internet, Financial Services, Education, Government, Healthcare, Media & Entertainment, Telecommunications, Retail
Skills
Experience Level
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Intermediate
Intermediate
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