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 pipelines or streaming data (Kafka, event ingestion APIs)Experience building data-intensive backend services at scaleExperience designing or working with middleware layers: API gateways, request pipelines, data transformation services or similarKnowledge of PHP and/or Java/SpringExperience integrating AI tooling into development workflows in a meaningful way: using agents, MCP servers, or AI‑assisted development at team levelActive contributions to open‑source projectsBenefitsWork on product that reaches publishers and newsrooms globallyOption to work full remote, hybrid or office‑based (if in BCN area)Support with home office equipmentFlexible hours and early finish on FridaysSubsidized health insurance for you and your partner/family (Adeslas)Subsidized monthly plan to a large network of health and wellness centers (Wellhub)Transport, restaurant and kindergarten tickets (Cobee)Free language classes (English/Spanish)Open‑space, light‑filled and eco‑conscious office with large sunny terrace (if BCN based)Unlimited refreshments including coffee, tea and soft drinks at the office (if BCN based)Loyalty vacation daysAccess to training platforms, courses and materialsReferral bonus for talent brought to us by you#J-18808-Ljbffr

📌 Backend Engineer (Madrid)
🏢 Marfeel
📍 Madrid