Kamil is available for hire
Hire KamilKamil Dobrzyński
Verified Expert in Engineering
JavaScript Developer
Remote, Poland
Toptal member since September 9, 2026
Bio
Kamil is a senior mobile engineer with 8 years of experience shipping consumer apps. He owns delivery from product scope and architecture through CI/CD and store release. He led Monster's native-to-React Native rewrite for apps with 11+ million downloads, shipped regulated payments at JPMorgan Chase UK, and owned UNLOQ end-to-end, taking it to #1 in Poland's App Store Entertainment category. His core stack is React Native, TypeScript, Expo, Swift, and Kotlin.
Portfolio
UNLOQ
React Native, TypeScript, Expo, Firebase, Next.js, UXCam, GitHub Actions...
ITI Implantology
React Native, TypeScript, Stripe, REST, Single Sign-on (SSO), AI SDK, Cursor AI...
Monster Worldwide
TypeScript, React Navigation, Fastlane, Swift, Kotlin, Firebase, Amplitude...
Experience
- JavaScript - 10 years
- Expo - 8 years
- React Native - 8 years
- TypeScript - 6 years
- Firebase - 6 years
- Swift - 6 years
- Leadership - 4 years
- Kotlin - 4 years
Preferred Environment
React Native, TypeScript, Expo, React Native Bridge, Monorepos, IT Security, Amazon Web Services (AWS), Technical Leadership, Software Architecture, Mobile Architecture, Next.js, Swift, Claude Code, iOS, Artificial Intelligence (AI)
The most amazing...
...app rewrite I've led was Monster's migration from two native apps to one React Native codebase with 11+ million combined downloads.
Work Experience
Mobile Team Lead
2026 - 2026
UNLOQ
- Owned the platform end-to-end: Expo/React Native app, Firebase Auth/Firestore/Cloud Functions, and a Next.js admin panel in a pnpm + Turborepo monorepo.
- App reached #1 in the App Store Entertainment category (Poland), powering Fame MMA pay-per-view access and partner campaigns with Superbet, OKX, and Bitpanda.
- Built the DevEx and release path: EAS Build, EAS Update (OTA), force-update gates, and GitHub Actions that deploy Cloud Functions automatically.
- Shipped Trading Challenge: live OKX/Bitpanda exchange-volume rankings, Vouch-based user verification, and real-time leaderboards.
- Built admin campaign tools: push-notification targeting, in-app WebView flows, deep linking, and UXCam/Crashlytics analytics used for the FIFA World Cup 2026 campaign.
Technologies: React Native, TypeScript, Expo, Firebase, Next.js, UXCam, GitHub Actions, Turborepo, EAS, Unit Testing, Jest, Vitest, Vite, React, React Router, React Query, React Hooks, React Hook Form, React Native Reanimated, React Navigation, Valtio, Zod Schema, Zod, React Native Testing Library, Firebase Analytics, Firebase iOS SDK, Firebase Android SDK, Firebase Cloud Functions, Firebase Security Rules, Firebase Authentication, Firebase Realtime Database, Firebase Cloud Messaging (FCM), Google Analytics for Firebase, Google Cloud Platform (GCP), Matomo, Matomo API, Sentry, Crashlytics, GitHub, GitHub CLI, GitHub Runners, Jira, GitHub Workflows, Cursor AI, Cloud Firestore, Monorepos, Leadership, Team Leadership, Technical Leadership, Software Architecture, Software Development, Mentorship, Mobile Development, Mobile App Development, Rapid Mobile Application Development (RMAD), App Store, App Store Connect, App Store Acceptance Process, App Store Optimization (ASO), Google Play API, Google Play Store, Google Play Console, App Development, Full-stack, APIs, Large Language Models (LLMs), Artificial Intelligence (AI), Front-end, Architecture, API Integration, Back-end, AI Agents, CSS, Web Development, Web, Web Design, Code Review, Source Code Review, Development, Design, Fractional CTO, Marketplaces, Git, MySQL, Software Engineering, Full-stack Development, English, System Architecture, HTML5, Docker, Node.js, AI Engineering, AI Voice Agents, Content Writing, Back-end Performance, Android App Development, Google Cloud Console, Front-end Design, Data Science, Data Analytics, CTO, Team Leadership & Supervision, Compliance, Prompt Engineering, A/B Testing, Machine Learning, Claude Code, Bug Fixes, iOS, iPhone, Data Extraction, IT Audits, Manual QA, Software Testing, Planning, User Experience (UX), User Interface (UI), Testing, Troubleshooting, GoHighLevel, Lead Generation
Mobile Team Lead
2025 - 2026
ITI Implantology
- Owned pre-sales scoping and estimation as mobile team leads; the proposal helped the software house win the contract.
- Ran delivery of the ITI App (AI content feed, community forum, Study Club, e-learning, e-commerce) across roadmap, change requests, beta, and store release.
- Designed the integrations: SSO/MS Dynamics membership, Stripe checkout, and an AI chatbot.
- Shipped the ITI App from greenfield MVP to store using Expo and EAS, with Detox and unit tests on the release path, while leading a 1-5 person mobile squad.
Technologies: React Native, TypeScript, Stripe, REST, Single Sign-on (SSO), AI SDK, Cursor AI, Claude API, Expo, EAS, Detox, Unit Testing, Leadership, Team Leadership, Sales, Estimations, B2B Sales, Push Notifications, Apple Push Notifications, Amazon S3 (AWS S3), Firebase Analytics, Sentry, Jira, Figma, React, React Router, React Query, React Hooks, React Hook Form, React Native Reanimated, React Native Testing Library, Amplitude, Firebase Cloud Messaging (FCM), Zod, Zod Schema, Zustand, Technical Leadership, Mobile Development, Mobile Architecture, Mobile App Development, Rapid Mobile Application Development (RMAD), Stripe API, Stripe Subscriptions, Stripe Checkout, Payments, Card Payments, Mobile Payments, Testing, E2E Testing, Accessibility, A11Y, App Store, App Store Connect, App Store Optimization (ASO), App Store Acceptance Process, Google Play Store, Google Play Console, App Development, Google Cloud Platform (GCP), Full-stack, APIs, Large Language Models (LLMs), Artificial Intelligence (AI), Front-end, Architecture, API Integration, Back-end, AI Agents, CSS, Code Review, Source Code Review, Development, Design, Fractional CTO, Marketplaces, Git, MySQL, Software Engineering, Next.js, Full-stack Development, English, System Architecture, HTML5, Docker, Node.js, AI Engineering, AI Voice Agents, Back-end Performance, Android App Development, Google Cloud Console, Front-end Design, Data Science, Data Analytics, CTO, Team Leadership & Supervision, Compliance, Prompt Engineering, A/B Testing, Claude Code, Bug Fixes, iOS, iPhone, Data Extraction, IT Audits, Manual QA, Software Testing, Planning, User Experience (UX), User Interface (UI), Troubleshooting, GoHighLevel, Lead Generation
Senior Mobile Engineer
2024 - 2025
Monster Worldwide
- Led the rewrite of Monster's flagship iOS and Android job search apps into one React Native CLI codebase, covering 11+ million combined downloads while maintaining feature parity.
- Kept shared native modules and migrated persisted user data, so existing users retained their sessions during the transition rather than being forced to log in again.
- Unified two native release trains into one Fastlane pipeline for iOS and Android, with Firebase Crashlytics, Messaging, Amplitude, Jest, and Detox on core job-search flows.
Technologies: TypeScript, React Navigation, Fastlane, Swift, Kotlin, Firebase, Amplitude, Jest, Detox, SwiftUI, Swift 6, Kotlin/Native, Mobile Development, Mobile Architecture, Mobile App Development, Rapid Mobile Application Development (RMAD), Leadership, Technical Leadership, React Native, React Native Bridge, React Native Reanimated, React Native Navigation, React Native Testing Library, React Query, React Hooks, React Hook Form, Zod, Zod Schema, Zustand, E2E Testing, IT Security, Migration, Mobile, Apple Push Notifications, Sentry, Matomo, Matomo API, Software Development, Software Architecture, Crashlytics, Firebase Cloud Messaging (FCM), CI/CD Pipelines, Data Migration, App Development, Large Language Models (LLMs), Artificial Intelligence (AI), Front-end, Architecture, API Integration, AI Agents, CSS, Code Review, Source Code Review, Development, Fractional CTO, Marketplaces, Git, Software Engineering, English, System Architecture, AI Engineering, Android App Development, Front-end Design, Data Analytics, CTO, Team Leadership & Supervision, Compliance, Prompt Engineering, A/B Testing, Text-to-Speech (TTS), Claude Code, Bug Fixes, iOS, iPhone, Data Extraction, IT Audits, Manual QA, Software Testing, Planning, User Experience (UX), User Interface (UI), Testing, Troubleshooting, GoHighLevel, Lead Generation
Senior Software Engineer
2024 - 2024
EY
- Refactored legacy React Native screens into reusable architecture and added Jest/Detox coverage on the critical learning flows.
- Hardened authentication, secure storage, and API communication, working with EY stakeholders on a government enablement product for Abu Dhabi.
- Improved offline behavior and SSO/keychain-based session handling while modernizing a live application with a substantial legacy JavaScript layer.
Technologies: React Native, TypeScript, React Navigation, Axios, Swift, Kotlin, Jest, Detox, IT Security, JavaScript, Authentication, Single Sign-on (SSO), Keychain, Secure Storage, Application Security, Software Development, Software Architecture, E2E Testing, Unit Testing, React Native Bridge, React Native Reanimated, React Query, React Hooks, React Native Testing Library, React Hook Form, REST, App Development, Large Language Models (LLMs), Artificial Intelligence (AI), Front-end, Architecture, API Integration, AI Agents, CSS, Code Review, Source Code Review, Development, Design, Marketplaces, Git, Software Engineering, Full-stack Development, English, System Architecture, AI Engineering, Android App Development, Front-end Design, Data Science, Data Analytics, Compliance, Prompt Engineering, A/B Testing, Text-to-Speech (TTS), Claude Code, Bug Fixes, iOS, iPhone, Data Extraction, IT Audits, Manual QA, Software Testing, Planning, User Experience (UX), User Interface (UI), Testing, Troubleshooting, GoHighLevel, Lead Generation
Senior Mobile Engineer
2023 - 2024
JPMorgan Chase
- Shipped production payment features for Chase UK in React Native and TypeScript as part of a 12-person payments squad - one of six teams supporting the app-only retail bank.
- Integrated GraphQL APIs for payment data, replacing ad-hoc REST fetching across production payment features.
- Closed gaps in automated test coverage across production payment features by adding Appium, Jest, and Detox tests for critical screens, components, and user flows.
Technologies: React Native, TypeScript, Swift, Kotlin, GraphQL, Appium, Jest, Detox, Fintech, Payments, Card Payments, Mobile, Mobile Development, Mobile Architecture, Mobile App Development, E2E Testing, Unit Testing, React Native Testing Library, React Query, React Hooks, React Hook Form, React Native Reanimated, React Navigation, React Native Bridge, Swift 6, SwiftUI, Kotlin/Native, IT Security, Application Security, Security, CI/CD Pipelines, Push Notifications, App Development, Front-end, Architecture, API Integration, CSS, Code Review, Source Code Review, Development, Marketplaces, Git, Software Engineering, English, Android App Development, Front-end Design, Data Science, Data Analytics, Finance, Compliance, A/B Testing, Text-to-Speech (TTS), Claude Code, Bug Fixes, iOS, iPhone, Data Extraction, IT Audits, Manual QA, Software Testing, Planning, User Experience (UX), User Interface (UI), Testing, Troubleshooting, Lead Generation
Mobile Team Lead
2023 - 2023
Fixvi
- Estimated the Fixvi mobile build during pre-sales, identifying the delivery scope, technical risks, and architecture before development began.
- Led a 4-person mobile team from greenfield development through App Store and Google Play release.
- Owned mobile architecture decisions and delivered native modules across Swift, Kotlin, and React Native.
- Established the production architecture using React Navigation Native Stack, Expo Modules, React Query, Valtio, Formik/Yup, i18next, and Reanimated.
- Built unit and end-to-end test coverage with Jest and Detox and integrated Sentry for production monitoring.
- Managed delivery risks, promoted engineering best practices, and coordinated technical decisions with the client and collaborating teams.
Technologies: React Native, TypeScript, Swift, Kotlin, React Navigation, React Query, Formik, Yup, i18next, Sentry, React Native Reanimated, Valtio, Jest, Detox, React Hooks, React Hook Form, React Native Bridge, React Native Testing Library, Unit Testing, E2E Testing, Leadership, Technical Leadership, Mobile, Mobile Development, Mobile Architecture, Mobile App Development, Rapid Mobile Application Development (RMAD), App Development, PostgreSQL, Google Cloud Platform (GCP), React, Full-stack, APIs, Large Language Models (LLMs), Artificial Intelligence (AI), Front-end, Architecture, API Integration, AI Agents, CSS, Web Development, Web, Web Design, Code Review, Source Code Review, Development, Design, Fractional CTO, Marketplaces, Git, Elasticsearch, Software Engineering, Next.js, Full-stack Development, English, System Architecture, HTML5, Docker, Node.js, AI Engineering, Android App Development, Google Cloud Console, Front-end Design, Data Science, Data Analytics, CTO, Team Leadership & Supervision, Compliance, A/B Testing, Bug Fixes, iOS, iPhone, Data Extraction, IT Audits, Manual QA, Software Testing, Planning, User Experience (UX), User Interface (UI), Testing, Troubleshooting, Customer Relationship Management (CRM), Lead Generation
Senior Mobile Engineer
2021 - 2023
Blaise Transit
- Shipped production features across the Blaise Transit passenger and Blaise Drive apps on iOS and Android.
- Introduced TypeScript into the existing React Native codebase, improving type safety and long-term maintainability.
- Built native navigation on iOS and Android with Mapbox and OSRM, integrating Swift, Objective-C, and Kotlin with React Native.
- Designed and implemented the driver navigation workflow from route assignment through active guidance and live rerouting.
- Improved live rerouting so buses avoided unnecessary u-turns when routes changed during active service.
Technologies: React Native, TypeScript, JavaScript, React, Next.js, React Navigation, React Query, React Hooks, React Hook Form, React Native Reanimated, React Native Bridge, React Native Testing Library, E2E Testing, Unit Testing, Mapbox, Mapbox GL, Mapbox API, Mapbox SDK, Mapbox iOS SDK, Mapbox Styling, Mapbox Datasets, Dynamic Routing, Vehicle Routing, Navigation, Objective-C, Java, Sentry, Zustand, Zod, Zod Schema, GPS, Android GPS, Mobile GPS, GPS Integration, GPS Tracker, Firebase, Firebase Analytics, Firebase iOS SDK, Firebase Android SDK, Firebase Cloud Messaging (FCM), Push Notifications, Apple Push Notifications, Mobile, Mobile Architecture, Mobile Development, Mobile App Development, Technical Leadership, Node.js, PostgreSQL, REST, Storybook, Stripe, Stripe API, Stripe Subscriptions, Payments, Mobile Payments, Card Payments, App Store, App Store Connect, App Store Optimization (ASO), App Store Acceptance Process, Google Play Store, Google Play Console, Brownfield, App Development, Google Cloud Platform (GCP), Full-stack, APIs, Artificial Intelligence (AI), Front-end, Architecture, API Integration, Back-end, CSS, Web Development, Web, Web Design, Code Review, Source Code Review, Development, Design, Fractional CTO, Marketplaces, Git, MySQL, Software Engineering, Full-stack Development, English, System Architecture, HTML5, Docker, Back-end Performance, Android App Development, Google Cloud Console, Front-end Design, Data Science, Data Analytics, CTO, Team Leadership & Supervision, Compliance, A/B Testing, Bug Fixes, iOS, iPhone, Data Extraction, IT Audits, Manual QA, Software Testing, Planning, User Experience (UX), User Interface (UI), Testing, Troubleshooting, Customer Relationship Management (CRM), Lead Generation
React Native Trainer
2022 - 2022
Cshark
- Designed and delivered a two-week React Native training program for CSHARK engineers, progressing from core concepts to production mobile delivery.
- Explained the differences between React and React Native, including the mobile runtime, platform APIs, and React Native Bridge architecture.
- Taught engineers how to design and implement native modules across Swift, Kotlin, and React Native.
- Covered push notification integration on iOS and Android, including native configuration and React Native application flows.
- Guided engineers through application signing, production builds, and releases using App Store Connect and Google Play Console.
- Led hands-on live-coding sessions that took participants from an empty project to a working cross-platform mobile application.
- Following the training, assembled three engineers into a four-person delivery team and led the Fixvi application from greenfield development to both stores.
Technologies: React Native, TypeScript, Google Maps, JavaScript, React, React Query, React Hooks, React Hook Form, React Native Reanimated, React Native Bridge, React Navigation, React Native Testing Library, Jest, Swift, Kotlin, App Store, App Store Connect, App Store Acceptance Process, Google Play Store, Google Play API, Google Play Console, Apple Push Notifications, Apple Maps, Apple Maps API, React VR, Mobile Architecture, Mobile, Mobile Development, Mobile App Development, Mobile UX, Mobile UI, Technical Leadership, Leadership, Team Leadership, Team Mentoring, LiveCode, Training, Technical Training, App Development, Front-end, Architecture, API Integration, CSS, Web, Web Design, Code Review, Source Code Review, Development, Design, Fractional CTO, Marketplaces, Git, MySQL, Software Engineering, Full-stack Development, HTML5, Node.js, Android App Development, Google Cloud Console, Front-end Design, Data Analytics, Team Leadership & Supervision, A/B Testing, iOS, iPhone, Data Extraction, Manual QA, Software Testing, Planning, User Experience (UX), User Interface (UI), Testing, Troubleshooting
Lead React Native Developer
2021 - 2021
Entia
- Joined Entia as the sole mobile developer responsible for delivering improvements across its React Native application for at-home hemoglobin testing.
- Implemented UI and UX improvements based on product designs, refining production screens and user flows across iOS and Android.
- Improved accessibility for disabled and elderly users across critical testing flows.
- Fixed production bugs and delivered incremental improvements across the React Native codebase.
- Built and improved chat-related screens and interactions within the mobile application.
- Extracted reusable components so new post-MVP flows could be delivered without duplicating screens.
Technologies: React Native, TypeScript, JavaScript, Mobile Development, Bluetooth, Push Notifications, Apple Push Notifications, App Store, App Store Connect, Google Play Console, Google Play Store, Accessibility, Accessibility Testing, Jest, Unit Testing, React Native Testing Library, React Native Navigation, Redux, React Redux, Redux-Saga, Redux Form, A11Y, Chart.js, Charts, Application Security, Problem Solving, Problem Structuring, Bug Fixes, System Improvements, CI/CD Pipelines, Fastlane, App Development, PostgreSQL, Google Cloud Platform (GCP), React, Full-stack, APIs, Front-end, Architecture, API Integration, Back-end, CSS, Web Development, Web, Web Design, Code Review, Source Code Review, Development, Design, Fractional CTO, Marketplaces, Git, MySQL, Software Engineering, Next.js, Full-stack Development, English, System Architecture, HTML5, Docker, Node.js, Back-end Performance, Android App Development, Google Cloud Console, Front-end Design, Data Science, Data Analytics, CTO, Team Leadership & Supervision, Compliance, iOS, iPhone, Data Extraction, IT Audits, Manual QA, Software Testing, Planning, User Experience (UX), User Interface (UI), Testing, Troubleshooting, Customer Relationship Management (CRM), Lead Generation
iOS Developer
2021 - 2021
Booksy
- Built and maintained SwiftUI views for the Booksy business app, using Combine for reactive state and data flows.
- Implemented UI and UX improvements based on product designs, polishing production screens and fixing visual inconsistencies.
- Built an internal debug panel for development and troubleshooting within the iOS application.
- Built a brownfield proof of concept that embedded React Native components inside SwiftUI views and synchronized state in both directions.
- Expanded from React Native into native iOS delivery, applying SwiftUI and Combine in a production product used by Booksy businesses.
Technologies: SwiftUI, Combine, Swift, Kotlin, React Native, React Native Bridge, Xcode, iOS App Development, Mobile App Development, Brownfield, Debugging, Xcode Playgrounds, App Development, Front-end, Architecture, API Integration, CSS, Code Review, Source Code Review, Development, Git, Software Engineering, English, Android App Development, Front-end Design, Data Analytics, Compliance, A/B Testing, Bug Fixes, iOS, iPhone, Data Extraction, IT Audits, Manual QA, Software Testing, Planning, User Experience (UX), User Interface (UI), Testing, Troubleshooting
Senior React Native Developer
2021 - 2021
Orange
- Delivered React Native features for Orange Flex, Orange's subscription-based mobile telecommunications product.
- Shipped the Eco GB transfer feature, enabling customers to convert unused mobile data into tree-planting rewards.
- Built ESLint locale-path suggestions across two separate application bundles, helping developers use the correct translation keys.
- Expanded Jest and Detox coverage across production mobile features and user flows.
- Fixed production issues and delivered UI improvements across the Orange Flex application.
Technologies: React Native, TypeScript, React Navigation, Formik, Yup, Jest, Detox, React Query, React Hooks, React Native Reanimated, React Hook Form, React Native Navigation, Redux, React Redux, Redux-Saga, Firebase, Firebase Analytics, Firebase Android SDK, Firebase iOS SDK, Firebase Cloud Messaging (FCM), Push Notifications, Apple Push Notifications, Mobile, Mobile App Development, Mobile Development, Software Development, App Development, Front-end, Architecture, API Integration, CSS, Code Review, Source Code Review, Development, Marketplaces, Git, Software Engineering, English, Android App Development, Google Cloud Console, Front-end Design, Data Science, Data Analytics, Compliance, Bug Fixes, iPhone, Data Extraction, IT Audits, Manual QA, Software Testing, Planning, User Experience (UX), User Interface (UI), Testing, Troubleshooting, Customer Relationship Management (CRM), Lead Generation
Mobile Developer
2020 - 2021
Versum (powered by Booksy)
- Shipped production features across two React Native applications: Versum for businesses and Moment for customer bookings.
- Designed and implemented mobile subscription and payment flows across the applications.
- Integrated GraphQL and Apollo Client to synchronize mobile functionality with the web platform.
- Built Detox end-to-end tests and a Storybook component library for the mobile development workflow.
- Implemented push notification flows and maintained production monitoring using Firebase, Notifee, and Sentry.
Technologies: React Native, TypeScript, GraphQL, Apollo Client, Redux, React Navigation, Sentry, Formik, Lottie, Firebase, Jest, Detox, Accessibility, A11Y, Accessibility Testing, i18next, i18n, Push Notifications, Apple Push Notifications, Payments, Stripe, Stripe API, Apollo, Storybook, Mobile Payments, Subscriptions, Stripe Subscriptions, React Redux, Redux Form, Redux-Saga, React Native Reanimated, React Native Testing Library, Unit Testing, Testing, E2E Testing, Mobile App Development, Mobile Development, Figma, App Development, PostgreSQL, Google Cloud Platform (GCP), React, Full-stack, APIs, Front-end, Architecture, API Integration, CSS, Web Development, Web, Web Design, Code Review, Source Code Review, Development, Design, Marketplaces, Git, MySQL, Software Engineering, Next.js, Full-stack Development, System Architecture, Node.js, Content Writing, Back-end Performance, Android App Development, Google Cloud Console, Front-end Design, Data Science, Data Analytics, Compliance, Bug Fixes, iPhone, Data Extraction, IT Audits, Manual QA, Software Testing, Planning, User Experience (UX), User Interface (UI), Troubleshooting, Customer Relationship Management (CRM), Lead Generation
React Native Developer
2019 - 2021
Jugendarbeit.digital
- Designed and built the Jugendapp mobile application end to end as its sole developer using React Native CLI.
- Built an interactive map connecting users with local events, activities, offers, and news across participating cities.
- Implemented direct messaging, support conversations, and comments within the mobile application.
- Built offline functionality with synchronization to the backend when connectivity became available.
- Implemented role-aware access to confidential content and administrative functionality.
- Added QR-code deep linking that directed users to relevant content inside the application.
- Integrated a VR experience into the mobile application.
Technologies: React Native, React Native Reanimated, React Navigation, React Native Navigation, JavaScript, TypeScript, RxJS, Redux, React Redux, Redux-Saga, Mobile Architecture, Mobile Development, Mobile App Development, Zeplin, React VR, Viro Media, Deep Linking, iOS App Development, Objective-C, Java, App Store, App Store Connect, App Store Optimization (ASO), App Store Acceptance Process, Google Play API, Google Play Store, Google Play Console, Firebase, Firebase iOS SDK, Firebase Android SDK, OneSignal, Rocket.Chat, Offline Caching, Offline Maps, Offline-first Development, Startups, Maps, Apple Maps, Google Maps, Apple Maps API, Solutioning, Bug Fixes, Process Improvement, System Improvements, Fastlane, CI/CD Pipelines, GitLab CI/CD, GitLab, GitLab Runner, Live Chat, Chatbox, Data Synchronization, Offline Data Synchronization, QR Codes, Engineering, App Development, PostgreSQL, Google Cloud Platform (GCP), React, Full-stack, APIs, Front-end, Architecture, API Integration, Back-end, CSS, Web Development, Web, Web Design, Code Review, Source Code Review, Development, Design, Wix, Marketing, Fractional CTO, Marketplaces, Git, MySQL, Software Engineering, Next.js, Full-stack Development, English, System Architecture, HTML5, Docker, Node.js, Content Writing, Back-end Performance, Android App Development, Google Cloud Console, Front-end Design, Data Science, Data Analytics, CTO, Team Leadership & Supervision, Compliance, A/B Testing, iOS, iPhone, Data Extraction, IT Audits, Manual QA, Software Testing, Planning, User Experience (UX), User Interface (UI), Testing, Troubleshooting, Customer Relationship Management (CRM), Lead Generation
Mobile Engineer
2020 - 2020
DocPlanner
- Led the technical transition from native applications to hybrid delivery across 13 country-specific app variants.
- Integrated React Native modules and components into existing Objective-C iOS and Groovy Android applications.
- Built a real-time chat feature as a separate React Native module embedded inside the native ZnanyLekarz application.
- Delivered the platform's 24/7 chat functionality during the COVID-19 period while maintaining the existing native applications.
- Migrated users from the legacy application to the new chat-enabled build.
- Delivered native bug fixes, dependency upgrades, and Android Gradle improvements across the brownfield codebase.
Technologies: Objective-C, Groovy, React Native, TypeScript, JavaScript, Firebase, Redux, Jest, React Native Bridge, React Native Reanimated, React Navigation, React Native Testing Library, Unit Testing, Accessibility Testing, A11Y, i18n, i18next, Accessibility, Firebase iOS SDK, Firebase Analytics, Firebase Android SDK, Firebase Cloud Messaging (FCM), Push Notifications, Apple Push Notifications, Crashlytics, Apple Maps, Google Maps, Apple Maps API, Maps, Google Play API, Google Play Store, Google Play Console, App Store Connect, App Store, App Store Acceptance Process, Chatbox, Live Chat, Mobile Architecture, Mobile Development, Mobile App Development, Software Development, Software Architecture, Brownfield, Offline Caching, App Development, Google Cloud Platform (GCP), Front-end, Architecture, API Integration, CSS, Code Review, Source Code Review, Development, Design, Fractional CTO, Marketplaces, Git, MySQL, Software Engineering, Full-stack Development, English, System Architecture, Docker, Back-end Performance, Android App Development, Google Cloud Console, Front-end Design, Data Science, Data Analytics, CTO, Team Leadership & Supervision, Compliance, A/B Testing, Bug Fixes, iOS, iPhone, Data Extraction, IT Audits, Manual QA, Software Testing, Planning, User Experience (UX), User Interface (UI), Testing, Troubleshooting, Lead Generation
Experience
W Sercach - Digital Memorial Platform
https://wsercach.pl/W Sercach is a digital memorial platform where QR plaques placed on gravestones connect families with online memory profiles. Kamil founded the company and owns the product end to end, from positioning, roadmap, and pricing through engineering and production operations. He designed and shipped the consumer mobile app, two web applications, backend services, and AWS infrastructure in a TypeScript monorepo. The product reached the App Store and Google Play in approximately four months and includes a B2B partner panel used by more than 10 funeral homes and stonemason partners in Poland. Kamil also implemented Stripe card and BLIK payments and continues to operate and improve the platform.
Education
2016 - 2020
Bachelor's Degree in Computer Science
Nicolaus Copernicus University In Toruń - Toruń
Certifications
MARCH 2021 - PRESENT
iOS Development Training
Sages
JULY 2020 - PRESENT
React Native: Advanced Concepts
Udemy
Skills
Libraries/APIs
React Navigation, React, Node.js, Stripe, React Query, Formik, Yup, Valtio, Apollo Client, Google Maps, Tamagui, React Hook Form, Zod, React Router, Recharts, OpenAPI, Auth, Claude API, Zod Schema, React Native Testing Library, Firebase iOS SDK, Firebase Android SDK, Matomo API, Google Play API, Apple Maps, Apple Maps API, Mapbox GL, Mapbox API, Mapbox iOS SDK, React Redux, Redux-Saga, Redux Form, Chart.js, Stripe API, RxJS, React Native for Web, GitHub API, REST APIs
Tools
Expo, Fastlane, Claude Code, Git, Google Cloud Console, Terraform, Firebase Analytics, Wix, Sentry, Vitest, Crashlytics, Amazon Cognito, AI SDK, Apple Push Notifications, Jira, Figma, Firebase Security Rules, Firebase Authentication, Firebase Cloud Messaging (FCM), Google Analytics for Firebase, Matomo, GitHub, GitHub CLI, Xcode, Xcode Playgrounds, Stripe Checkout, Chatbox, Zeplin, Viro Media, OneSignal, GitLab CI/CD, GitLab, GitLab Runner, Claude, Android Studio, AWS Deployment, Canva
Languages
TypeScript, Swift, JavaScript, HTML, CSS, HTML5, Kotlin, C, GraphQL, Objective-C, Groovy, Java, SQL, Swift 6, LiveCode, C++
Frameworks
React Native, Next.js, Jest, Detox, Appium, i18next, SwiftUI, Combine, Redux, Tailwind CSS, Fastify, Serverless Framework, Swagger, React VR, UIKit
Paradigms
Testing, App Development, Software Testing, REST, Unit Testing, Mobile Development, Rapid Mobile Application Development (RMAD), E2E Testing, Brownfield, App Store Optimization (ASO), Offline-first Development
Platforms
Firebase, iOS, Web, Docker, GoHighLevel, AWS IoT, Google Cloud Platform (GCP), Bitrise, Mapbox, AWS Lambda, Amazon Web Services (AWS), Mobile, Keychain, Rocket.Chat, Android
Storage
PostgreSQL, MySQL, Cloud Firestore, Amazon DynamoDB, Amazon S3 (AWS S3), SQL Server Management Studio (SSMS), Firebase Realtime Database, Data Synchronization, Elasticsearch
Industry Expertise
Web Design, Marketing
Other
Leadership, Bug Fixes, Full-stack, Large Language Models (LLMs), Artificial Intelligence (AI), Front-end, Architecture, API Integration, AI Agents, Web Development, Code Review, Source Code Review, Development, Design, Fractional CTO, Marketplaces, Software Engineering, Full-stack Development, English, System Architecture, AI Engineering, AI Voice Agents, Back-end Performance, Android App Development, Front-end Design, Data Science, CTO, Team Leadership & Supervision, Compliance, Prompt Engineering, A/B Testing, Machine Learning, Text-to-Speech (TTS), Model Evaluation, Text-to-text Transfer Transformer (T5), iPhone, Data Extraction, IT Audits, Manual QA, Planning, User Experience (UX), User Interface (UI), Troubleshooting, Customer Relationship Management (CRM), Lead Generation, Serverless, APIs, Back-end, Content Writing, Email Marketing, Data Analytics, Finance, UXCam, GitHub Actions, Turborepo, Single Sign-on (SSO), Amplitude, Axios, React Native Reanimated, Lottie, EAS, Azure Pipelines, React Hooks, Zustand, TanStack Query, Monorepos, Storybook, Vite, Radix UI, FCM, Remote Config, Algorithms, Cursor AI, Team Leadership, Sales, Estimations, B2B Sales, Push Notifications, Firebase Cloud Functions, GitHub Runners, GitHub Workflows, React Native Bridge, IT Security, Technical Leadership, Software Architecture, Mobile Architecture, Software Development, Mentorship, Mobile App Development, Kotlin/Native, React Native Navigation, Migration, CI/CD Pipelines, Data Migration, Authentication, Secure Storage, Application Security, Fintech, Payments, Card Payments, Security, App Store, App Store Connect, App Store Acceptance Process, Google Play Store, Google Play Console, Mobile UX, Mobile UI, Team Mentoring, Training, Technical Training, Mapbox SDK, Mapbox Styling, Mapbox Datasets, Dynamic Routing, Vehicle Routing, Navigation, GPS, Android GPS, Mobile GPS, GPS Integration, GPS Tracker, iOS App Development, Debugging, Bluetooth, Accessibility, Accessibility Testing, A11Y, Charts, Problem Solving, Problem Structuring, System Improvements, i18n, Apollo, Mobile Payments, Subscriptions, Stripe Subscriptions, Maps, Live Chat, Offline Caching, Deep Linking, Offline Maps, Startups, Solutioning, Process Improvement, Offline Data Synchronization, QR Codes, Engineering, React Native IAP, Hooks, Git Hooks, Pipelines, AI Pipeline, Online Payments, Stripe Payments, Amazon Cognito User Pools, API Gateways, Terraform Cloud, Deployment, Product Owner, Product Ownership, Product Engineering, Production Engineering, Analytics, Application State Management
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