# Senior Android Engineer- Hardware at SumUp

- Company: SumUp
- Status: Open
- Workplace: On-site
- Location: Berlin, Germany
- Level: Senior
- Discipline: Backend
- Employment: Full-time
- Posted: 2026-09-22
- Skills: Android
- Apply: https://sumup.com/careers/positions/8794602002?gh_jid=8794602002

## Description

Team description
 The Hardware tribe builds the technology that turns everyday devices into secure, reliable card readers, from Bluetooth-connected dongles to fully in-house Tap to Pay on Android. You'll join a team solving genuinely hard problems: keeping payments working across flaky Bluetooth connections, handling online and offline flows without losing a transaction. It's a chance to go deep on Android engineering in a space where reliability really matters, since every merchant depends on these readers to get paid.
 What you'll do
• 
 Build and maintain Android applications for card readers, SDKs, and the SuperApp, covering both new features and improvements to existing systems
• 
 Work on Bluetooth Low Energy connections, online and offline payment flows, and Tap to Pay functionality
• 
 Refactor and modernise legacy code to improve reliability, performance, and maintainability
• 
 Contribute to testing practices, including unit and integration tests, to raise overall code quality
• 
 Collaborate with peers and stakeholders across the team to manage priorities and shape solutions to technical challenges
 You'll be great for this role if...
• 
 Several years of professional Android development experience, with solid proficiency in both Java and Kotlin
• 
 Strong knowledge of clean architecture principles and hands-on experience maintaining Android SDKs
• 
 Experience of writing unit and integration tests, and comfort refactoring legacy code without breaking existing functionality
• 
 Familiarity with CI/CD pipelines, such as GitHub Actions, and an interest in improving

More SumUp roles: https://deviantjobs.com/companies/sumup