Senior Software Engineer (Madrid)

Fullstack Engineer

We’re hiring Fullstack engineer with a product mindset who loves building scalable systems and polished user experiences. We’re creating a platform where customers can manage subscriptions, billing, invoices, payment methods, and usage insights through seamless self‑service experiences built on a modular, scalable architecture with best‑in‑class service design.

Factorial is building a world‑class platform to support customers and partners to interact with our products, manage their accounts, and grow with us. As a Fullstack engineer in the Portals team, you’ll build and evolve customer facing portals that enable secure, intuitive, and scalable self‑service experiences.

You’ll design and integrate systems that connect internal platforms—billing, CRM, product services, and support—with external users, ensuring reliable access to key workflows across the customer lifecycle. Your work will directly impact how customers and partners interact w...