The RoleWe are looking for a Backend Engineer to join a small, high-ownership engineering team working on new product initiatives. You will be primarily focused on new product initiatives, building new services and features, though you may occasionally need to navigate existing codebases. You use AI coding tools as a core part of how you work, and you are excited about what that unlocks. You will own backend architecture decisions and work closely with product and data to ship reliable, high-performance services at scale.This Is What You Will DoDesign, build and maintain backend services using Node.JsWork with large-scale data systems, including ClickHouse and other relational and non-relational databasesBuild and maintain APIs that power our analytics product, working across real-time and historical datasetsEnsure services are performant, scalable, and maintainableContribute to architectural decisions for new product featuresWork in an Agile environment with short, focused sprintsCollaborate closely with product,



data and frontend teamsThis Is You5+ years of experience building backend services in production environmentsStrong proficiency in Node.Js and TypeScriptSolid experience with relational and non-relational databases (MySQL, MongoDB, ClickHouse or similar columnar databases)Deep understanding of API design, data modeling, and web architectureStrong focus on performance: you think about query efficiency, latency and scale by defaultYou use AI coding tools: Claude Code, Cursor, Copilot or similar, as a natural part of your development workflow, not as an afterthoughtExperience with CI/CD pipelines and cloud deployments (Docker, GitHub Actions, Jenkins or similar)You enjoy working on complex technical problems and take ownership of your solutionsFamiliar with testing practices including unit, integration and end-to-end testingWe Will Be Impressed By Experience InExperience with ClickHouse or other OLAP / columnar databasesFamiliarity with real-time data pipelin

📌 Backend Engineer (Madrid)
🏢 Marfeel
📍 Madrid