SDET - Quality Infrastructure

SumUp builds financial tools that help millions of small merchants run and grow their businesses. Within this mission, the Global Bank Team is responsible for creating the foundation of SumUp’s digital banking platform - used by merchants across multiple regions. As we scale, we're investing heavily in developer experience, automation, and productivity.

About the Role
We’re looking for a Software Development Engineer in Test who can supercharge how 200+ engineers build and ship banking features. You’ll create the tools, infrastructure, and platforms that eliminate friction, improve reliability, and raise the engineering bar across the tribe - directly shaping the pace and quality of SumUp’s global banking platform. If you want to prove that great tooling can be a competitive advantage, this is the place to do it.

What You’ll Work On:

Infrastructure & Platforms

• Build performance monitoring and regression-detection platforms
• Create reusable data-generation systems and merchant/transaction factories
• Develop shadow-traffic and automated validation infrastructure
• Implement foundations for deterministic, automation-gated deployments

Developer Productivity & Tooling

• Improve CI/CD reliability, speed, and observability
• Build internal SDKs, CLIs, and automation frameworks
• Drive adoption of contract testing and integration-first patterns
• Create workflows that turn production incidents into automated coverage

Architecture & Systems

• Modernize automation architecture and integration patterns
• Design tooling that reduces deployment lead time and boosts confidence
• Embed with squads to understand pain points and ship high-leverage solutions

What Success Looks Like:

• 60%+ reduction in manual validation
• Faster lead time across all squads
• 70%+ integration coverage with better tooling
• Fully automated Dev/Staging deployments for all teams

What You Bring:

Engineering Excellence

• Experience programming in Kotlin, Go, Python, Java, or similar
• Built internal tools, SDKs, or frameworks used by other engineers
• Deep understanding of microservices, event-driven systems, and CI/CD
• Hands-on with Docker, Kubernetes, AWS, and modern observability stacks

Developer Experience Expertise

• Improved CI/CD or DevEx tooling at scale
• Experience with performance testing, distributed tracing, load testing
• Designed integration/testing frameworks or developer automation

Mindset

• You optimize for leverage, not ticket throughput
• You care deeply about developer happiness and productivity
• You collaborate, embed with teams, and take ownership
• You thrive in autonomy and low-bureaucracy environments

Nice to Have:
Experience with Kafka, Pact, fintech environments, PostgreSQL, developer portals, or open-source tooling.

Why you should join SumUp

• We’re a truly global team of 3200+ people from 80+ countries, spread across 4 continents
• 25 days annual leave + Birthday Leave
• A dedicated annual Learning & Development budget (2000Euro / year) for attending conferences and/or advancing your career through further education
• Enrollment onto our virtual stock ownership program - you will own a stake in SumUp’s future success
• The opportunity to work on large scale fintech products used by millions of businesses around the world
• Health Insurance, Death & Disability Insurance
• Access to the SumUp Sabbatical, our Employee assistance program for mental health as well as Fitness and Transport allowance and language learning benefits.
• You’ll attend global offsites and/or hackathons.

Salary range: 4375 - 7000 Euro GROSS / month + Virtual Stock Options + 2000 Euro/ year Learning & Development budget 

About SumUp

We believe in the everyday hero.

Small business owners are at the heart of all we do, so we create powerful, easy-to-use financial solutions to help them run their businesses. With a founder’s mentality and a 'team-first’ attitude, our diverse teams across Europe, South America and the United States work together to ensure that the small business owners we partner with can be successful doing what they love. 

SumUp is an Equal Employment Opportunity employer that proudly pursues and hires a diverse workforce. SumUp does not make hiring or employment decisions on the basis of race, colour, religion or religious belief, ethnic or national origin, nationality, sex, gender, gender identity, sexual orientation, disability, age or any other basis protected by applicable laws or prohibited by company policy. SumUp also strives for a healthy and safe workplace and strictly prohibits harassment of any kind.

SumUp will not accept unsolicited resumes from any source other than directly from a candidate. 

Job Application Tip

We recognise that candidates feel they need to meet 100% of the job criteria in order to apply for a job. Please note that this is only a guide. If you don’t tick every box, it’s ok too because it means you have room to learn and develop your career at SumUp.