Experteer Overview As a Staff Software Engineer at Factorial, you will lead technical initiatives around AI-native features, shipping production-ready capabilities built with LLM APIs. You’ll work closely with Product and Design, writing Rails and React to shape scalable systems that real customers rely on. This role emphasizes end-to-end ownership, mentorship, and driving architectural decisions in a fast-growing, product-driven environment. You’ll help define how AI features are designed, tested, and operated at scale, balancing reliability and compliance. Compensaciones / Incentivos • Lead important technical initiatives and set architectural direction for meaningful roadmap areas • Collaborate very closely with Product and Design from early conversations to implementation • Own systems end-to-end from problem framing to production rollout and maintenance • Engage with customers to gather feedback and inform product decisions • Shape AI features at scale, including design, build,



and operation of AI-native experiences • Promote spec-driven development with clear success criteria and constraints • Build reusable, scalable, and secure components used by multiple product domains • Develop modular, traceable AI skills and governance tooling for reliability • Contribute to a culture of high engineering standards, mentoring, and process improvement • Maintain data reliability by combining LLM outputs with deterministic sources of truth • Raise the engineering bar across hiring, practices, and collaboration Responsabilidades • Solid depth in both backend and frontend software engineering • Experience shipping real production products, not just prototypes • Strong understanding of APIs, cloud platforms (AWS, Azure, or GCP), and system design • Experience integrating LLM APIs into product features and shipping to real users • Seen as a technical and cultural leader with high standards • Ability to push back on ineffective processes and drive adoption of new abstractions •

📌 Staff Software Engineer (Barcelona)
🏢 Factorial Hr
📍 Barcelona