Senior Android Engineer, AdTech (m/f/d)

Description

The company is Europe's largest e-pharmacy and runs its own mobile app. This Android role sits in a cross-functional product team and is listed as Senior Mobile Engineer (Android/iOS).

The work centres on Retail Media and sponsored advertising inside the app, where sponsored products and personalised recommendations must sit alongside a strong shopping experience for millions of customers across Europe.

You would have high visibility and direct influence on how the Android platform grows.

Tech stack: Kotlin, Android SDK, Jetpack Compose, Android Jetpack (ViewModel, Navigation, DataStore), Coroutines and Flow, Hilt (Dagger), Retrofit/OkHttp, Ktor and Koin.

Responsibilities

• Lead the design and build of scalable, maintainable, high-performance Android apps in Kotlin, applying patterns such as MVVM, MVI and Clean Architecture.
• Define and evolve the Android architecture so it stays scalable, modular, testable and easy to maintain over time.
• Drive wider use of Jetpack Compose to create declarative, reusable and responsive interfaces.
• Build reusable mobile components for Retail Media, including Sponsored Products, Sponsored Brands, native placements, display banners and personalised product recommendations.
• Fit Retail Media placements into product discovery, search, category, product detail and other shopping journeys, balancing revenue goals with customer experience.
• Work with backend, data, product and ad server teams on APIs, tracking contracts, campaign metadata, targeting, attribution and measurement.
• Build configurable solutions so new ad formats, placements, campaigns and monetisation use cases can be added quickly.
• Set standards for modularisation, code quality, testing and performance, and improve CI/CD reliability, build speed and release processes.
• Own observability, dependency management, security, app stability and overall technical health.
• Keep architecture decisions, features and technical processes well documented.
• Review key technical and architectural decisions and help set engineering standards across teams.
• Reduce technical debt where it pays off, and deliver platform improvements that help product teams.
• Build and evolve feature flags, experimentation and A/B testing to measure new customer and advertising experiences.

Requirements

• Extensive Android development experience with strong Kotlin skills.
• Deep knowledge of the Android SDK and current Android development practices.
• Hands-on work with Jetpack Compose, Coroutines and Flow, dependency injection with Hilt or Dagger, and REST APIs with Retrofit or OkHttp.
• Solid grasp of clean architecture principles, design patterns and modularisation.
• Experience testing with JUnit, Espresso and MockK, and writing maintainable, testable code.
• Familiarity with CI/CD pipelines and modern development workflows.
• Proven ability to take ownership of complex projects and deliver high-quality results independently.
• Strong focus on performance, scalability and user experience.
• Good debugging and performance optimisation skills, and you collaborate effectively across teams.
• Experience in Retail Media, AdTech, MarTech or large-scale e-commerce platforms.
• Cross-platform experience is an add-on.

Conditions

If the role does not require office presence, the place you work from can be arranged individually, including up to 20 days a year anywhere in the EU.

Benefits

• Sports: a membership (M) package at Urban Sports Club, giving access to a wide variety of sport offers.
• Mental health: quick, free and anonymous support from psychologists at Likeminded when you feel overwhelmed in private or professional life.
• Mobility: a fully costed Deutschland Ticket that can be used at any time.
• Personal development: support and encouragement through internal and external training.
• Further benefits are available.