Portfolio

Last updated: October 2024

I’m open to opportunities and available for consulting, contracting, and freelance engagements. If you’re interested, you can find more details here.

  • Apple platforms
    • Very proficient in Swift and Objective-C
    • Extensive experience with UIKit and SwiftUI, async/await, Swift Macros, Swift Charts
    • Operating Systems: iOS, iPadOS, watchOS, tvOS, macOS
  • Java platform
    • Very proficient in Java, experience in Kotlin
    • Extensive experience with JEE, web applications, REST, JSON, SQL, OAuth
    • Notable frameworks: Spring Boot, Quarkus, Apache Wicket, JOOQ, Hibernate, JavaFX, Angular
  • Other
    • Strong debugging and analytic thinking skills
    • OO design and programming
    • Functional programming
    • Relational database design
    • Continuous Integration and Continuous Delivery
    • Backend for Frontend (BFF) pattern
    • UI testing
ING Germany
ING Germany
Independent Contractor (Java)
Nuremberg • Remote • July 2024 —

Web application for bank customer service to efficiently conduct all financial services by phone

  • Implementation of new features
  • Support for upgrade to new Java version
  • Adjustments to changed regulatory requirements
  • Bug fixing
  • Implementation of automated tests to verify compliance with development guidelines and ensure software quality
  • Operations and deployment support
Clue
Biowink GmbH
Senior Software Engineer
Berlin • Remote • Sep 2022 — Apr 2024

Building and maintaining the iOS app Clue Period Tracker & Calendar

  • Took part in the reimplementation of the existing app written in Objective-C, leveraging a modern stack with SwiftUI and adopting async/await programming paradigms.
  • Assisted in backend development within a microservices architecture environment as needed, utilizing Kotlin.
  • Contributed to streamlining the deployment process using fastlane in combination with GitHub Actions.
  • Enhanced the continuous integration setup, resulting in a substantial reduction of UI test execution time.
  • Coordinated the technical integration of data from Oura smart rings into backend systems. Developed data visualization features for sleep duration within the app using Swift Charts.
  • Operated successfully in an international work environment, collaborating with colleagues from over 17 different countries. Worked within regulatory requirements in a medical setting, as the app is classified as a Class B medical device.
Exaring
Exaring AG
Senior Software Engineer iOS
Munich • Hybrid • Sep 2017 — Jul 2022

Building and maintaining the iOS and tvOS apps for waipu.tv and O₂ TV

  • Created the framework architecture and project setup enabling the development for various platforms and different brandings from a unified codebase.
  • Developed and refined significant portions of the tvOS app.
  • Held responsibility for a reliable video player.
  • Implemented key features for the iOS app (the electronic program guide, a VOD media library, and user recordings).
  • Invented a new login mechanism for big screens and coordinated with the development teams from other platforms. Helped with patent application process and invention documentation.
ING Germany
ING Germany
Senior Software Engineer & Tech Lead iOS
Nuremberg • On-site • Oct 2014 — Aug 2017

Building and maintaining the iOS banking app for ING Germany

  • Oversaw team build up as first full-time iOS developer at ING Germany.
  • Planned and implemented the basic infrastructure and project setup to support a modular app, allowing different ING departments to maintain and contribute core features.
  • Implemented core functionality for transferring money directly within the app.
Gymder
Gymder
Independent Contractor (Android, iOS)
Munich • Remote • Jul 2016 — Jul 2017

Contributed to the development of the Gymder fitness app, a social fitness tool that connects gym enthusiasts for workout partnerships. Collaborated on iOS and Android development to enhance user experience and functionality, focusing on turning workouts into social interactions.

ING Germany
ING Germany
Senior Software Engineer Java
Nuremberg • On-site • Apr 2012 — Sep 2014

Development of internal web applications for authorization management and call center agents

  • Architecture and implementation of an IT platform for workflow-supported authorization management, utilizing current development tools and frameworks such as Spring, Hibernate, Wicket, JUnit, Mockito, and QueryDSL.
  • Managed the provisioning and operation of the IT authorization platform in the production environment, including the Oracle Waveset Identity Manager.
  • Took part in the conception and implementation of an internal web application for call center agents, used during customer calls to perform account operations after successful customer authentication. Technologies used include Wicket, Jenkins, Nexus, JUnit, Mockito, Spring.
  • Ensured adherence to development guidelines and maintained software quality through automated IT tests
SBB
Schweizerische Bundesbahnen SBB
Independent Contractor (Java, OpenGL)
Berne, Switzerland • On-site • Jan 2012 — Mar 2012

Helped out with prototyping and performance tuning

  • Prototype implementation of the train schedule rendering component for train dispatchers using OpenGL.
  • Performance tuning of rendering and adjustments to the dispatcher client written in Java using Eclipse RCP.
Lumatix
Lumatix
Co-Founder & Lead Engineer
Erlangen • Hybrid • Sep 2010 — Jan 2012

Co-founded Lumatix and lead development of Lumatix Atrium Designer, a 3D real-time visualization middleware.

  • Evaluation and implementation of various approaches and scientific publications on Real-time Global Illumination.
  • Design and implementation of the graphics routine and core component of the product in C++, OpenGL, and OpenCL.
Spirit Link
Spirit Link GmbH
Independent Contractor (Java)
Erlangen • Hybrid • Apr 2009 — Aug 2010

Technical consultation and implementation of various Java projects

  • Consulting and implementation projects for Novartis on dotCMS with Java.
  • Maintenance of a price list management tool using Java and Eclipse RCP for Siemens.
Spirit Link
Spirit Link GmbH
Senior Software Engineer Java
Erlangen • On-site • May 2001 — Mar 2009

Technical management and implementation of multiple projects in the Java/JEE environment for companies such as Siemens AG, Novartis Oncology, and Areva NP.

  • Development of Java-based web applications and rich-client applications.
  • Architectural design, modeling, and programming. Leadership of project-specific development teams of up to 6 people.
  • Areas of expertise include knowledge and document management, as well as medical image processing.

I’m involved in a few side projects and indie apps. While many of them are not (yet) publicly available, they represent my ongoing exploration of diverse domains and technologies.

Birthday Reminder
2012 — Present

An app designed to help users remember the birthdays of their loved ones, fostering stronger connections through timely reminders.

LWT27
2022 — Present

A home automation app focused on controlling window blinds, enhancing convenience and energy efficiency in everyday life.

Mobook
2020 — 2021

A specialized audio player app tailored for Apple Music, with a particular emphasis on delivering an exceptional experience for audiobook enthusiasts.

PINO-LA
2016 — 2022

A Java-based desktop application dedicated to ETIM classification and feature capture, streamlining data classification and attribute capture processes.

AKAD University
AKAD University
Diploma in Business Informatics (University of Applied Sciences)
Stuttgart, Germany • Sep 2005 — Apr 2009

Specialization: Computer-Integrated Systems, Software Development, Networking
Grade: Very Good (1.3)

German

Native

English

Fluent