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Senior Java Engineer - Online Payments

Berlin, Germany · Engineering

As a Senior Java Engineer in the Online Payments Tribe, you’ll be part of the team supporting SumUp’s Business growth by providing a scalable, secure and global Online Payments Platform which will facilitate all Card not Present (CNP) transactions - meeting the Online Payments needs of our customers and enabling them to grow.

We are building our platform using the latest technology and we want you to help us raise the bar and drive these changes. As a team, we use Java, Kubernetes, Kafka, Cassandra, Postgres, and Rest API. We are looking for an innovative Developer who likes to explore technology.

Are you up for the challenge? If so, here is a flavour of what awaits you as Senior Java Engineer:

  • Design, implement and iteratively create back-end services

  • Maintain and evolve the team core services

  • Participate in API design and implementation for both internal APIs and those exposed to our third-party integrators

  • Help your team deliver business value by taking decisions related to the back-end and actively participate in product discussions and code reviews with other engineers

  • Provide comprehensive documentation, good test coverage, and improve code quality

  • Collaborate with other software developers to ensure smooth deployment, continuous integration and support for the software we deliver


  • You have 8+ years of experience as a back-end developer.

  • You have relevant experience in Java (11 or newer) programming.

  • You’re familiar with AWS, Kubernetes (user, not admin experience)

  • You have experience with distributed and fault-tolerant systems.

  • You have a passion for automated tests and CI/CD

  • Kafka, Cassandra, Postgres are not unknown to you

  • You have a mature and business minded approach to your work

  • You have a passion for clean, maintainable, and testable code.

  • You understand fundamental system architecture, design principles, data modelling, and API design (RESTful services)

  • You have great verbal and written English communication skills.

  • You are open and collaborative 


  • You will work in a truly global team of 2000+ people from 60+ countries, spread across 3 continents.

  • You'll attend global off-sites and regular team events.

  • You’ll receive a budget for attending conferences and external training.

  • We offer a corporate pension scheme, 28 days’ paid leave. 

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, color, 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 an individual/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.