Matthias Zarzecki
iOS Freelancer (Senior)
Experience
Jan 2025 - Present
5 monthsRemote
iOS Developer
Allianz Versicherung
- Developed the Allianz App Focus: iOS, Jenkins, A11Y, SonarQube, Fastlane
Sep 2024 - Mar 2025
7 monthsRemote
Lead Apple Watch & iOS Developer
Calima
- Developed an Apple Watch App for Worker Safety Focus: iOS, WatchOS, WatchKit, Falling Down API, Sentry, Bluetooth, IoT
Sep 2024 - Dec 2024
4 monthsRemote
iOS Developer
Bitmarck
- Developed the Bitmarck Whitelabel App for 30 Health Insurances Fokus: iOS, Jenkins, MS AppCenter, Firebase, A11Y, NFC, CryptoKit, ProtoBuf
Aug 2024 - Sep 2024
2 monthsRemote
Lead VisionOS Developer
ShapedAgency
- Developed an Augmented Reality App for the Apple Vision Pro Fokus: iOS, VisionsOS, RealityKit
Jul 2024 - Sep 2024
3 months Potsdam, Germany
On-siteFlutter Developer
MicroMovieMedia
MicroMovieMedia GmbH
- Flutter-Developer for a whitelabel app for museums
- Developing the QR Scanner
- Developed audio streaming component Focus: Flutter, Dart, GoRouter, QR Recognition
Apr 2024 - Jun 2024
3 months London, United Kingdom
RemoteLead Apple Vision Pro VR Developer
Unit9
- Apple Vision Pro & iOS Native Lead to several Unity-Developers for an Augmented Reality App fo the Apple Vision Pro Focus: VisionOS, Apple Vision Pro, RealityKit
Sep 2023 - Apr 2024
8 months Stuttgart, Germany
HybridSenior iOS Developer
Stihl
- Developed a Bluetooth Connectivity IoT App Focus: CoreBluetooth, IoT, Combine, UIKit, Microsoft App Center, Github Actions, Azure DevOps
Jul 2023 - Sep 2023
3 months Berlin, Germany
HybridSenior iOS Developer
KptnCook
- Featured on the App Store
- Worked on new iOS 17 Widgets before release
- Transitioned database to new concept Focus: UIKit & SwiftUI Architecture Transition, Widgets, Realm
May 2022 - Aug 2023
1 year 4 monthsRemote
Senior iOS Developer
Chrono24
- Developed the Chrono24 iPhone & iPad App
- Worked on the Augmented Reality Watch Scanner
- Introduced new practices which have been adapted across the entire codebase Focus: DIKit, Datasource & Repository Architecture, UIKit & SwiftUI Architecture Transition, Modularization, Async Await Actors, AVFoundation
Jun 2021 - Aug 2022
1 year 3 monthsRemote
Senior iOS Developer
OneCode (aka Red Android)
OneCode (aka Red Android) Worked as external developer for various projects.
- Worked on internal vehicle-management app for Telekom
- Introduced new linter standards to codebase & notably Increased amount of unit-tests
- Integrated Apple Health into the Bosch eBike App
- Worked on Apple Watch integration & MapBox features and integration
- Worked in SAFe project structure with 10 other scrum-teams
- Setup CICD Infrastructure for Unu Motors iOS & Android E-Moped Apps from scratch Focus: SwiftUI, Combine, Fastlane, Bitrise, MapBox, Apple HealthKit, Apple WatchKit, Visual Studio App Center, Lottie
Jun 2020 - Sep 2020
4 months Berlin, Germany
RemoteVirtual Reality Engineer
Neomento
- Developed the Neomento Virtual Reality Therapy tool for the Charité Berlin Focus: Unity3D, Vuforia, HTC Vive
Jul 2019 - Sep 2019
3 monthsRemote
Augmented Reality Engineer
Bauhaus Museum Weimar
- Created an Augmented Reality app for iPads that is used in Workshops at the museum Focus: Unity3D, Vuforia
Jun 2019 - May 2021
2 years Berlin, Germany
On-siteSenior iOS & Lead Flutter Developer
Oetker Digital
Oetker Digital & All About Cake
- Maintained & developed the Backen.de app for iOS and the Juit E-Commerce App using Flutter (latter as Lead Developer)
- Reduced deployment and build times by 90%, codebase size by 73%
- Maintained & Improved CICD using Bitrise & Fastlane
- Featured on the Apple App Store Focus: Swift, SwiftUI, Flutter, Dart, Combine, Fastlane, Bitrise, Firebase, Realm, Bluetooth, IoT
Apr 2017 - May 2019
2 years 2 months Berlin, Germany
On-siteMobile & DevOps Engineer
IBM iX
- Developed apps for Volkswagen, the Techniker Krankenkasse, Adidas, and others using Swift, Flutter and Unity3D
- Created an Augmented Reality App for live floor recognition & replacement
- Developed CICD systems using Fastlane, Bitrise, Sonarqube, Terraform & Vault
- Developed an UI Testing Development Solution that has been implemented by multiple departments Focus: Swift, Jenkins, Fastlane, MapBox, Vuforia, CoreML, Flutter, Dart, Unity3D
Summary
- 10+ years of experience, 30+ developed projects, 6 VR/XR projects
- Worked for: IBM, Dr. Oetker, Volkswagen, Telekom, Techniker Krankenkasse, Bosch, Chrono24, STIHL
- Award Winning Developer
- Mobile CI/CD Expert
- Engaged with SwiftUI Since Day 1
- Highly engaged in the iOS Dev Community, Fastlane Contributor
- Has own iOS Development YouTube Channel (matthias_code)
- Has own successful apps in store (Basketball Standings, Bluetooth Developer)
- Own apps with 40000+ downloads and Top 2 AppStore Chart Rankings
- Fluent in English & German, basics in French, Spanish, Dutch, Polish, Italian
Languages
English
Native
German
Native
Education
Sep 2012 - Aug 2016
HTW Berlin
Bacherlor's of Science · Computer Science · Berlin, Germany
Bachelor in media & computer science, Specialization in iOS Apps & VR Graduated with Special Award "Best IT-Project at the HTW Berlin 2016"
Certifications & licenses
Certified Scrum Master
SCRUM.org · Berlin, Germany
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