Maciej Korzeniewski
Verified Expert in Engineering
Mobile Developer
Maciej is an experienced mobile developer skilled in Flutter, iOS (Objective-C/Swift), and Android (Java/Kotlin) app development. He excels in setting up CI/CD pipelines with Bitrise/Codemagic for automated building, testing, and deploying to app stores. Maciej is well-versed in Firebase products like Firestore, Crashlytics, and Authentication. He also has experience in Node.js and TypeScript for server-side applications and uses React for web development.
Portfolio
Experience
Availability
Preferred Environment
MacOS, Slack, Flutter, Firebase, TypeScript, Node.js
The most amazing...
...thing I've done was leading and developing Hamilton — The Official App, available for both Android and iOS.
Work Experience
Native Swift/Kotlin Developer
Visible - Activity tracking for Long Covid and ME/CFS
- Built a premium feature that allows the Visible app users to gather health-related data from Polar devices using Polar SDK.
- Implemented storing health-related data in an encrypted, on-device database.
- Executed uploading health-related data to the back end.
- Implemented the Python back end running on Google Cloud Run that processes uploaded health-related data and calculates metrics based on it.
Flutter/Swift/Kotlin SDK Developer
beaconsmind AG
- Implemented binding for Flutter/React Native/Ionic in iOS/Swift and Android/Kotlin for the company's SDK.
- Developed pipelines that automate deployments of multiple native iOS and Android apps, saving the company a lot of time and cumbersome work as it was done manually before.
- Designed a user-friendly flow to request permissions required by the SDK (Bluetooth, location, and notifications).
Tech Lead
Very Good Ventures
- Led the re-architecture of the Hamilton Musical app.
- Co-developed an open-source web project called Photobooth for the Google I/O event. It allowed people to take a photo, add assets and share it with friends on social media.
- Co-created apps for Homethrive Inc. with incorporated video streaming using Twilio SDK.
- Improved testing skills by providing the apps with 100% test coverage.
- Deployed apps to the App Store and Google Play Store using phased or incremental rollout.
Mobile Developer
Freelance
- Contributed to the development of a home budget assistance app.
- Developed the mobile app with fine-grained UI using Flutter.
- Designed the offline-first architecture based on Firebase Firestore.
- Added authentication with external providers (Google, Facebook, and Apple).
- Implemented a recommendation system based on Firebase Dynamic Links.
- Incorporated a premium subscription program using IAPs (Apple Pay and Google Pay).
Mobile Developer
LeanCode
- Implemented a GPS tracking module for Android in Kotlin.
- Co-created Activity Challenges, an activity GPS tracker and game, with React Native and Redux.
- Developed the Shell Fleet Assistant, a fleet management app in Xamarin and MvvmCross.
- Added real-time chat functionality with React Native, Redux, and Firebase Firestore for BeautyClick, a finding beauty specialist app.
Experience
Hamilton Flutter Mobile App
http://hamiltonmusical.com/You can find the app on Google Play here: http://play.google.com/store/apps/details?id=com.hamilton.app and on the App Store here: http://apps.apple.com/us/app/hamilton-the-official-app/id1255231.054
Flutter/Swift/Kotlin SDK Development
I also developed pipelines to automate deployments of multiple apps that the company owns.
Home Budget Assistance App
http://billy.inout.money/Native Swift/Kotlin developer integrating with health armband
http://www.makevisible.comSkills
Languages
Dart, TypeScript, Swift, Kotlin, Python
Frameworks
Flutter, Redux, React Native, .NET Core, Ionic
Libraries/APIs
REST APIs, Node.js, React
Paradigms
Mobile Development, Testing
Platforms
Firebase, Mobile, Xamarin, iOS, Android
Other
Deployment, Crash Reporting, Crash Fixing, Minimum Viable Product (MVP), Automated UI Testing, Code Coverage, Fitness, Data Structures, Networking
Tools
Figma
Storage
Cloud Firestore
Education
Master's Degree in Computer Science
Technical University of Denmark - Denmark
Bachelor of Engineering Degree in Computer Science
Warsaw University of Technology - Warsaw, Poland
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