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Senior Erlang / Elixir Backend Engineer

Boulder · New Business

Backend Engineer (Elixir)

We are the leading mobile point-of-sale (mPOS) company in Europe and growing fast in the US. Our vision as a global FinTech company is to empower small merchants at doing what they love all over the world by delivering beautiful and intuitive services to merchants. With small business deployments in over 31 countries around the world that rely on SumUp to get paid, we are well on our way! Our startup mindset and boldness of action, combined with our empathy and love for product innovation, foster a creative environment for our employees.  We value an entrepreneurial spirit and seek to build lasting relationships among our team members. We are committed to a diverse and inclusive workforce which keeps us competitive and provides opportunities for all. We believe that together we can help small businesses grow; to achieve that goal, we are assembling an awesome team that is committed to one another and to our merchants. You could be our missing link!  Help us bring card acceptance to the masses!

Your impact at SumUp

As part of our vision to become a truly global tech company, we are building local, autonomous, cross-functional teams that are empowered to take an aspect of our product and perfect it from concept to execution. In Hardware, our goal is to envision and beautifully design our products, making sure they are prepared for payment and security specifications. We are passionate about our product and the vision of bringing new payment solutions to small merchants. 

Our terminals delegate a significant part of the payment logic to the backend, giving us the flexibility and speed which our merchants require from us. As a Backend Engineer, you will be supporting the team with delivering those features and maintaining existing ones - transaction flows for different payment methods, firmware updates, and other integrations with our internal services.

Your role and responsibilities

  • Design, implement, and iteratively improve backend services in Elixir

  • Maintain and extend the core payments system, responsible for the transaction flow for different payment methods and written in Erlang

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

  • Help your team to deliver business value by making decisions related to backend and actively participating in the product discussions

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

  • Collaborate with other software, QA and sysops engineers to ensure smooth deployment, continuous integration, and support for the software that we deliver

  • Actively participate in code reviews with other software engineers

Does it describe you? 

  • You have 5+ years of experience as a backend engineer 

  • You have relevant experience with Elixir and OTP (whether in a production environment or from pet projects)

  • You have a good understanding of software architecture and application design

  • You have experience with distributed and fault tolerant systems

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

  • You value team over individuals and autonomy within your team

  • You are humble, transparent and enjoy working with the people around you

  • You are proactive and able to thrive in a fast-paced, dynamic environment

Awesome if you: 

  • Are active in Elixir community, contribute to open source or have personal projects

  • Enjoy mentoring fellow engineers and love sharing knowledge

  • Worked in an international, distributed team

  • Have experience with Docker and/or Kubernetes

  • Feel comfortable with Unix/Linux environments

Why work for SumUp? 

  • Be part of a close, welcoming international community of more than 1,600 people from over 52 nationalities. We get together regularly for brunches, cocktail nights, and office parties

  • Budget for attending conferences and advancing your career. We encourage you to speak at conferences and deliver presentations!Semi-annual off-sites, where the tech teams from Boulder, Berlin, Sofia, and São Paulo gather together. In the past, we've gone to Spain, Bulgaria, Greece and a castle in the countryside of Germany

  • Prime office location on Pearl Street (Downtown Boulder)

  • Health, dental, vision and life insurance

  • FSA & 401K Retirement Plans

  • Immediate PTO available upon hire

  • Startup environment and small, cross-functional teams  

  • Fun: weekly team events and SumUp US milestone celebrations

  • Free rotating beer selection, fruits, and organic snacks

  • Free Bus Pass and discounted Gym Memberships

  • 1 additional PTO Powder/Outdoor day - this is why we live in Boulder, right?

Apply now!

We're looking forward to meeting our next teammate! You can also choose whether to include a CV, your LinkedIn profile, a link to your github, tech blog, or portfolio – whatever you think will give us your complete picture.

You do not need to match every listed expectation to apply for this position. Here at SumUp, we believe that diverse perspectives foster innovation, and we are committed to building a team that encompasses a variety of backgrounds, experiences, and skills.

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.