Dirk Rosenau - Android Development

About

Me

I am a software developer with 15+ years of professional experience, focused on Android since 2014. In recent years, I have expanded into Kotlin Multiplatform and backend development. I work with an agile mindset, value clear collaboration, and prioritize clean architecture with maintainable, high-quality code.

Services

Android app development
Kotlin Multiplatform feature development
Architecture, code quality, and refactoring
Performance and stability optimization
Test automation
Team support and technical mentoring

Technologies

Android, Kotlin, Java, KMP, Coroutines, Flow, Jetpack Compose, RxJava, Hilt, Room, Retrofit, WearOS, Mockito, JUnit, MockK, Espresso, Ktor…

Selected Projects

BITMARCK

Project: White-label health insurance app

Further development of a white-label app used by statutory health insurance providers.

Tech: Kotlin, Jetpack Compose, Coroutines, Koin, JUnit, Mockito, MockK, Jenkins

TUI Cruises

Project: Mein Schiff app

Feature development and maintenance for the Mein Schiff mobile experience.

Tech: Kotlin, Java, Jetpack Compose, RxJava, Hilt, Coroutines, JUnit

Trade Republic

Project: Bond trading feature

Built the new bond trading experience in the Trade Republic app.

Tech: Kotlin, Jetpack Compose, RxJava, Hilt, JUnit

Techniker Krankenkasse

Project: TK-Safe module

Developed core functionality for the electronic health record module in the TK app.

Tech: Kotlin, XML, Jetpack Compose, RxJava, Dagger 2, Espresso, JUnit

Parfumerie Douglas

Project: E-commerce mobile app

Contributed to development of the Parfumerie Douglas e-commerce app.

Tech: Kotlin, Java, RxJava, JUnit, Espresso, Mockito, MockK