Senior Fullstack Engineer

Senior Fullstack Engineer Únete a nosotros 🔥 We’re Kabilio , a company backed by two leading venture capital firms, founded by experienced entrepreneurs, Alex Valls and Jose Ojeda , with a strong track record in building and scaling successful tech companies. What We’re Building Our goal is to become the go-to Financial Operating System for accounting firms and SMEs in Southern Europe , unifying accounting, tax, payments, planning, and banking into a single platform. We are currently a tight-knit team of 65 people and plan to grow in 2026, with a strong focus on engineering, product design, and sales. Why this role matters? Today, Kabilio already runs three core products in production Invoices — Processing, Bank Transactions, and Invoicing — used daily by real customers. At the same time, we’re building our Accounting platform, the product that defines our long-term vision and the reason Kabilio was founded. AI sits at the core of everything we build, from automating and categorizing financial data to enabling intelligent workflows and decision making across the entire financial lifecycle . It is also part of how we work as engineers, helping us move faster while building smarter product capabilities. As a Full Stack Engineer at Kabilio, you will build and own product features end-to-end, working closely with Ivan, CTO, Jorge, Karel and Arnau, Tech Leads, as well as the developers and Product Managers. You’ll contribute to both frontend and backend systems, helping us ship high-quality software that is used daily by real customers. You’ll work in a small technical team where engineers take real ownership of what they build, from early design decisions to production. What you’ll do? Use modern tooling (including AI-powered tools and internal integrations) to accelerate development and explore solutions (e.g. Claude Code). Work in an AI-augmented development workflow , using tools that help engineers explore documentation, understand the system, and move faster when building features (e.g. Claude Code combined with integrations in Linear, Notion, Slack). Design, build, and maintain full-stack features across our products. Work with React/Remix on the frontend and Node.js on the backend. Participate in the design of systems and architecture decisions to ensure scalability and long-term maintainability. Ensure code quality through testing, reviews, and best practices. Make pragmatic trade-offs to ship quickly while keeping long-term maintainability in mind. Contribute to building and integrating AI-powered features within the product when appropriate. What we offer? Salary range: Competitive salary (TBD in the first call) + Flexible benefits via Cobee. Hybrid setup : 3 days/week in our Barcelona office. Indefinite Spanish Contract + top work equipment Opportunity : Enter a massive market ready for disruption. We have a clear strategy to make our mark in Spain, leveraging what we have seen in other markets. Collaborative and Growth Culture : We prioritize open communication and respectful discussions. Your ideas will have a real impact, and you will have the chance to shape and grow with the business What should you bring to the table? Solid fundamentals in software design and system architecture. Strong interest in working with AI-enabled products and AI-augmented development workflows. Ability to work autonomously while collaborating with a team. Technical ownership. Strong experience building production web applications, ideally with React and Node.js. Good understanding of relational databases (PostgreSQL or similar). Care for clean code, maintainability, and best practices. Professional level Spanish, and English (B1 should be enough). Above all, you’re a reliable and trustworthy person. 🎢 Hiring process Video call with Talent→ Get to know you each other (30 mins) Video call with a Tech leads (30 minutes) Technical test Test debrief with Ivan Rodriguez (1 h) Meeting with founders on-site → Job offer 🔛 Departamento Tech Puesto Full Stack Engineer Ubicaciones Oficina Barcelona (anterior) Estado remoto Híbrido Acerca de Kabilio Somos un equipo multidisciplinar que une desarrollo, producto y experiencia contable para construir la nueva generación de herramientas de automatización con IA. Súmate a Kabilio y ayuda a reinventar la contabilidad Fundada en 2024 Compañeros 52