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 / Incentivos Alan private health insurance Wellhub fitness benefits Cobee expense management Language classes Breakfast in the office and organic fruit Pet friendly workplace Responsabilidades 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 Requisitos principales 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 leadership cross-functional collaboration clear communication Ruby on Rails React APIs and system design

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