Senior Backend Engineer

# Senior Backend Engineer ## About the Role Rivero is a fast-growing European fintech company headquartered in Switzerland and a Visa Fintech Partner, specialising in SaaS solutions for fraud recovery, dispute management, and payment scheme compliance. You will join a collaborative, product-focused engineering team working on **Kajo**, a distributed application built around event sourcing and designed to support customers and internal scheme compliance experts. As a Senior Backend Engineer, you will expand Kajo with new features, maintain and improve the existing codebase, design new parts of the technology stack, and build tools that support internal operational workflows. You will also use AI coding tools as part of your daily engineering workflow, contribute beyond a strict backend scope when useful, and share your technical knowledge with fellow engineers. ## Key Responsibilities * Develop new features and improvements for the Kajo application. * Maintain existing codebases, identify technical pain points, and propose effective solutions. * Build tools that help internal users manage operational workloads. * Lead the design and implementation of new components as product requirements evolve. * Use AI coding tools as a core part of the engineering workflow and help the team improve how these tools are used to increase development speed and code quality. * Contribute to frontend tickets and end-to-end development tasks when needed. * Collaborate closely with engineers and other team members in a distributed, product-focused environment. * Share technical knowledge, experience, and perspectives to support and enable other engineers. * Apply strong attention to detail, particularly around edge cases, implementation quality, and review processes within a regulated fintech environment. ## Required Qualifications * Professional experience developing cloud-based and web applications. * Proficiency in Kotlin or another JVM language, or exceptional expertise in a modern backend programming language with the ability to learn Kotlin quickly. * Experience working with distributed web applications. * Experience with relational databases. * Experience designing application APIs. * Hands-on, regular use of AI coding tools such as Claude Code in day-to-day engineering work. * Willingness and ability to work beyond a strict backend scope when required, including frontend tasks or end-to-end testing. * Strong communication and collaboration skills. * Strong attention to detail and the ability to identify edge cases. * Ability to work effectively in a fast-moving, iterative environment. ## Preferred Qualifications * Experience with event sourcing systems and CQRS. * Experience with GraphQL. * Familiarity with Go. * Familiarity with TypeScript and Vue.js or broader frontend development experience. * Familiarity with infrastructure and DevOps technologies such as Docker, Kubernetes, Terraform, GitLab CI, Elastic Stack, Prometheus, Traefik, Vault, Google Cloud Platform, or Nix. * Experience working with or contributing to AI-assisted software development practices. ## Technical Environment ### Kajo Backend Stack * **Languages:** Kotlin, Go * **Event Sourcing:** Axon Framework * **Web:** Ktor, GraphQL, Hasura * **Database:** jOOQ, Flyway, PostgreSQL * **Messaging:** NATS * **Identity & Access Management:** Keycloak ### Broader Technology Stack * **Frontend:** TypeScript, Vue.js * **Backend:** Java, Kotlin, Go, Scala, Rust, Haskell * **Infrastructure:** Docker, Kubernetes, Terraform, GitLab CI, Elastic Stack, Prometheus, Traefik, Vault, Google Cloud Platform, Nix ## Work Environment & Culture Rivero operates with a focus on urgency, ownership, excellence, continuous growth, collaboration, and transparency. The company uses an open-book management approach and encourages employees to understand the wider business context and contribute to company success. You will work in an international startup environment with opportunities to take ownership, learn continuously, and collaborate across disciplines. ## Location & Work Arrangement * On-site presence at Rivero's Zurich office is preferred. * Remote candidates are welcome when working within a timezone reasonably aligned with Zurich. * The Zurich workspace is located approximately two minutes from Oerlikon station. * Co-working spaces are available for employees in select locations. ## Benefits * Collaborative workspace and co-working options in select locations. * International startup culture with ownership and growth opportunities. * Peer-led academy sessions and continuous learning opportunities. * Regular social events and bi-annual company events in Zurich. * Five additional days beyond the annual holiday allowance for volunteering or community work. * Dog-friendly office. * Flexible choice of preferred hardware. * Mobile subscription allowance. * Stock option opportunities.