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# Ai Software Developer - Founding Role - Factorial Hr

- **Company:** Factorial Hr
- **Location:** Madrid, Spain
- **Contract:** Permanent contract
- **Skills:** Artificial Intelligence, Cloud Engineering, Code Review, Ruby on Rails, TypeScript, ReactJS, Backend, Front End Software Development
- **Published:** September 29, 2026
- **Apply:** https://www.buscojobs.com.es/ai-software-developer-founding-role-factorial-hr-en-madrid-ID-373416060

## About the Role

Experience shipping AI-powered features
Proficiency with Ruby on Rails backend and React frontend
Ability to explain complex technical decisions to non-technical audiences
Entrepreneurial mindset and experience building from scratch
Comfort with probabilistic systems and integrating AI models into scalable environments
Ability to translate non-deterministic outputs into actionable guidance
Ability to explain technical concepts clearly
Problem-solving under uncertainty
Ruby on Rails

## Description

Founding engineer role shaping a new Factorial spinoff focused on making AI central to workflow management.You'll own big initiatives, define quarterly roadmaps, and work closely with cross-functional teams to ship usable AI features.The role blends fast execution with thoughtful, reliable design in a cloud-native stack.You'll join a scrappy, highly capable team that values impact, mentorship, and continuous learning.Cobee for expensesLanguage classesBreakfast in the office and organic fruitPet-friendly officeOwn large initiatives and quarterly roadmapsParticipate in customer calls to understand pains and needsReview code daily and provide feedback across the teamMentor junior engineers and share knowledgeLearn from and contribute to performance and architecture discussionsCollaborate to build AI-integrated features in Ruby on Rails + React/TypeScript4+ years in software engineeringExperience shipping AI-powered featuresProficiency with Ruby on Rails backend and React frontendAbility to explain complex technical decisions to non-technical audiencesEntrepreneurial mindset and experience building from scratchComfort with probabilistic systems and integrating AI models into scalable environmentsAbility to translate non-deterministic outputs into actionable guidanceAbility to explain technical concepts clearlyProblem-solving under uncertaintyRuby on RailsReactTypeScriptAI Software Developer - Founding role - Factorial HR barcelona, catalunya, es#J-*****-Ljbffr