Overview

We are building a new startup inside Factorial, aiming to scale from 0 to 10 million in under a year. The new spinoff focuses on rethinking how companies manage workflows, org charts, policies, and analytics—core operational facets of Factorial’s platform. As a Founding Engineer, you will join at day zero, working closely with a small, high‑energy team that values speed, decision‑making with incomplete data, and building products people actually use.
Key Responsibilities

Lead the design, development, and delivery of AI‑powered features for the IT Management domain, including onboarding, permissions, support, and equipment management.
Own the full lifecycle of features—from hypothesis, to build, to deployment, measurement, and iteration.
Conduct customer calls to understand pain points and translate them into product requirements.
Review and mentor code daily, providing constructive feedback to all team members, including juniors.
Collaborate with the product team to set quarterly goals and roadmap, focusing on technical readiness and alignment with business objectives.




Advise teammates on transitioning from deterministic to probabilistic AI models, ensuring outputs can be reasoned about and acted upon.
Ensure scalable, cloud‑native integration of AI models with a Ruby on Rails backend and a React/TypeScript frontend.
Get involved in architectural decisions concerning agentic workflows and LLM trade‑offs.
Participate in recruiting, interview, and mentoring processes to grow the engineering team.
Qualifications

4+ years of software engineering experience, preferably with a track record of shipping AI features.
Strong experience in Ruby on Rails and React or TypeScript.
Proficiency in building and maintaining scalable backend services, integrating AI models, and ensuring reliability.
Hands‑on understanding of LLM architecture, agentic workflows, and probabilistic systems.
Ability to explain complex technical concepts in clear English to non‑technical stakeh

📌 Senior Product Engineer (Madrid)
🏢 Factorial Hr
📍 Madrid