Backend Engineer - Payments Team

Join a fast-growing, listed company with a purpose! Fastned owns and operates a network of 400+ fast charging stations across 10 European countries, allowing electric vehicle drivers to charge their car with 100% green energy in just 15 minutes. Our goal is a European network of 1000 fast charging stations in prime locations, where all electric vehicles can charge with renewable energy from the sun and wind. We have recently been voted best charging network in the UK, France and the Netherlands. If you want to make a difference and work in an informal, international scale-up environment with future prospects, then read on! Your role Fastned aims to accelerate the transition towards sustainable mobility by giving fast charging to electric drivers. Part of that mission is making car charging as simple as charging your phone, and paying for it should be just as effortless. As a Backend Engineer in the Payments team, you will help make paying for a charge frictionless, secure and reliable. Drivers can pay through the Fastned app, by QR code or with a contactless card at the charger. The team owns Fastned’s payments domain end to end. That covers integrations with payment service providers and payment terminals. It also covers the services behind payment methods, wallets, pre-authorisation and session payments, billing, invoicing and dunning. The stakes are high: Fastned handles 23,000+ charging sessions a day, and every one of those payments goes through our systems. We’re now moving towards real-time payments, where each session is paid instantly instead of invoiced later. As we are growing and adding roaming features as a Mobility Service Provider, there are many scale relevant challenges to solve. We have no legacy systems. You’ll work with Kotlin 2.x, Java 21+, and Spring Boot 4 on most services, AWS, Kubernetes, Kafka, SQL (Postgres), Terraform, GitLab CI/CD and REST APIs to build scalable, fault-tolerant services that drivers and our Finance team rely on every day. We encourage responsible AI usage and provide tooling like Claude Code, Codex, Dust . You’ll work closely with the other product teams, alongside fellow Backend Engineers, Data, Design, an Engineering Manager and a Product Manager in a Scrum setup. This role suits an engineer who enjoys a complex domain, cares about getting the details right, and wants to grow by taking real ownership of business-critical systems. Your overall responsibilities include Designing, developing, testing and reviewing reusable, maintainable and scalable code Working AI-first: using AI-augmented engineering, agentic workflows and AI tooling as a natural part of how you design, build, test and review, with judgement for where AI is a multiplier and where humans stay in the loop; Taking ownership from discovery to post-production; Taking operational responsibility for what you build, including monitoring, alerting and incident analysis; Helping improve engineering methodologies and best practices Who we are looking for In order to be successful in this role, you bring a strong sense of ownership and a pragmatic, proactive mindset. You enjoy working in a collaborative scale-up environment where things can change quickly and where taking initiative matters. Additionally, you tick the following boxes: You have 3+ years of professional backend experience, with strong hands-on Kotlin and/or Java experience. You have previous experience in the payments domain. You have experience working in agile teams within an international, multicultural environment. You have experience building and operating microservices in production, using REST APIs, cloud platforms and relational databases. You are familiar with event-driven architectures and technologies such as Kafka. You care about reliability, maintainability and the operational impact of the software you build. You spot opportunities and problems and pick them up yourself instead of waiting fo