Matthias Zarzecki - iOS Freelancer (Senior)

Berlin, Germany

Experience

Jan 2025 - Present

5 months

Remote

iOS Developer

Allianz Versicherung

Developed the Allianz App Focus: iOS, Jenkins, A11Y, SonarQube, Fastlane

Sep 2024 - Mar 2025

7 months

Remote

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 months

Remote

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 months

Remote

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-site

Flutter 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

Remote

Lead 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

Hybrid

Senior 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

Hybrid

Senior 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 months

Remote

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 months

Remote

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

Remote

Virtual Reality Engineer

Neomento

Developed the Neomento Virtual Reality Therapy tool for the Charité Berlin Focus: Unity3D, Vuforia, HTC Vive

Jul 2019 - Sep 2019

3 months

Remote

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-site

Senior 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-site

Mobile & 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