Senior Software Engineer - Payments & Customer Engagement

Senior Software Engineer - Payments & Customer Engagement Be part of a small, agile team that designs, builds, and owns products from concept to launch. Join our highly skilled team of developers – breaking new ground and shaping the future of retail. We dare to dream big, we have the courage to keep raising the bar, and we’re committed to being a force for good in retail - helping both established and fast-growing brands meet the ever-changing expectations of their customers. Sitoo is a fast-growing technology company exploring how far we can take innovation to deliver the world’s best Unified Commerce Platform and Point of Sale. Our technology is used in more than 20 countries - a number that keeps growing thanks to our incredible team of engineers. And we have no intention of slowing down. Are you the Senior Software Engineer we’re looking for? Your mission at Sitoo As a Software Engineer at Sitoo, you’ll join a small, autonomous team building and evolving our next-generation platform. This is a fullstack role but with a strong backend focus, where you’ll work across the stack but spend most of your time designing, building, and improving backend services. You won’t just write code and hand it over – you take ownership of the full lifecycle: design, development, deployment, operation, and continuous improvement. At the same time, you’ll contribute to frontend applications when needed, ensuring a seamless and high-quality user experience. A big part of your work will involve making thoughtful technical decisions, improving system architecture, and ensuring that what we build is scalable, reliable, and maintainable over time. About the team The Payments & Customer Engagement team develops, maintains, and operates Sitoo’s payment and customer engagement integrations. We connect the POS platform with CRM and loyalty systems to enable seamless customer recognition, personalized interactions, and smarter in-store experiences. By ensuring reliable data flows between systems, we help retailers create more connected customer journeys, strengthen loyalty programs, and deliver a more consistent user-experience. What you’ll do In this role, you will design, build, and operate backend services with a strong focus on performance, scalability, and reliability. While your main focus is backend, you’ll also contribute to frontend development when needed to ensure a seamless user experience. You’ll take end-to-end ownership of Sitoo’s web products, improving both functionality and technical foundations over time. Working in AWS, you’ll help evolve existing infrastructure and keep a close eye on system health through monitoring, alerts, and observability. You’ll collaborate closely with your team to improve processes and tooling, write tests to maintain high quality, and contribute to CI/CD pipelines and engineering best practices. What you’ll work with Backend: Node.js (core focus) Frontend: React, TypeScript Cloud: AWS Architectures: APIs, event-driven systems, distributed systems Practices: CI/CD, automated testing, Infrastructure as Code What you bring to the table Strong experience in backend development with Node.js Solid experience building and maintaining scalable cloud services Experience working across the stack (frontend + backend), with a backend-heavy focus Good understanding of distributed systems and asynchronous architectures Experience with modern CI/CD practices and cloud platforms (AWS, Azure, or GCP) Ability to take ownership of systems in production, including monitoring and improving them over time A pragmatic, product-oriented mindset with focus on real user value Fluent in English, both written and spoken Bonus points Experience with payments solutions Experience with AWS services such as SQS, SNS, DynamoDB, Lambda, or Aurora Familiarity with Docker or Kubernetes Experience with observability and incident handling in production systems Familiarity with AI-assisted development tools like GitHub Copilot or Cursor Why Sitoo We are forward thinkers. By turning curiosity into knowledge — and knowledge into continuous improvement — we break new ground and shape the future of retail. We believe in an inclusive culture where everyone feels like they belong. We support each other, win together, celebrate success together, and overcome challenges together. Today, we are close to 100 dedicated experts with a positive and solution-oriented mindset. Most importantly, we take care of each other — and we never forget to have fun. This is a hybrid role based in Stockholm or Gothenburg. Please note that we are currently unable to offer relocation support for this position, so you’ll need to hold a permanent residence permit in Sweden. Department Product & Engineering Role Backend Locations Stockholm, Sweden , Gothenburg, Sweden Remote status Hybrid The Sitoo Brand Values The hoodie among suits We believe in an inclusive culture where everyone feels empowered to be themselves, fully. We have a diversity of experience, perspectives and personalities, and believe this leads to a stronger team and a better product for our customers. As long as we’re knowledgeable, curious and focused on getting the right things done, we can be professional and relaxed at the same time. The hug among handshakes We treat our colleagues, partners and customers like we treat our friends. We help and guide, with a positive and solution oriented mindset. If there’s an issue we deal with it straight away. Breaking new grounds requires trust, and we believe that putting quality and reliability first and always having our customers’ best interest in mind makes all else follow. The tomorrow among yesterdays Driven by passion we look to the future, acting brave and dreaming big. With a can-do attitude we push the limits of what’s possible by turning curiosity into knowledge, and knowledge into innovation. We lead by inspiring others and just like Senseis we gladly share what we know and learn along the way.