Experteer Overview As a Staff Software Engineer at Factorial, you will shape AI-native features from end to end, collaborating closely with Product, Design, and Engineering to ship production-ready capabilities. You’ll work with Rails and React, designing scalable systems and guiding technical direction for meaningful roadmap areas. You’ll lead cross-functional initiatives to build reusable AI components and reliable, compliant product experiences. This role offers impact across a fast-growing, mission-driven company building with LLM APIs and agentic workflows. Compensaciones / Ventajas • Set technical direction for meaningful roadmap chunks and make architecture decisions • Collaborate tightly with Product and Design from the earliest planning stages • Own end-to-end systems from problem to production rollout and long-term maintenance • Engage with customers to capture real problems and feed context back into solutions • Define how to build AI features at scale,



ensuring reliability and compliance • Promote spec-driven development with clear success criteria and edge-case handling • Create reusable components and abstractions usable by other teams • Design and evolve modular AI skills that automate workflows and ensure safe actions • Build monitoring and quality tooling (automatic and human-in-the-loop) • Ground AI outputs in trusted data sources, balancing flexibility and determinism • Raise engineering culture through mentoring and better practices • Avoid roles focused on model training or fine-tuning as this is product engineering with LLM APIs Responsabilidades • Solid depth in both backend and frontend software engineering • Experience shipping real products to production • Understanding of APIs, cloud platforms (AWS, Azure, or GCP), and system design • Experience integrating LLM APIs into product features and shipping to users • Proven leadership and ability to influence technical direction and culture • Ability to advocate for effective processes, hiring, and deployment practices • Experience building scalable, secure, and governable components • Clear English communication; Spanish a plus Requisitos principales • Alan private health insurance • Wellhub fitness benefits • Cobee expense management • Language classes • Breakfast in the office and organic fruit • Pet friendly workplace

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