Founding Engineer

HelloDo you want to help us redefine how AI powers the future of Business Management software, not as an add-on, but as a core part of how people work, decide and grow?We’re looking for engineers who:Treat AI as central to their craft, not a feature to bolt on laterWant to build and ship, not debate and documentCare about whether the thing they built actually worked — not what their title says.Join us as a Founding Engineer in a brand-new Factorial spinoff ðWe're building a new startup inside Factorial, starting from scratch, with real backing and a clear target: 0 to 100 million by 2030 It's ambitious, and that's the point.The focus is on rethinking how companies manage workflows, org charts, policies, and analytics, the operational core of what Factorial does.

¿Tiene las habilidades necesarias para este puesto? Lea todos los detalles a continuación y presente su candidatura hoy mismo.

But this isn't an internal project.

It's a spinoff with its own identity, its own pace, and its own team.The advantage of doing this inside Factorial? We're not starting cold.

We have 17,000+ existing customers, a dedicated GTM team, and the infrastructure to move fast.

You'll be joining at day zero, but with a real runway.In terms of what we're building, the tech matters less than you'd think.

We care about your ability to move fast, make good decisions with incomplete information, and build things people actually want to use.

That said, strong Ruby on Rails experience on the backend and solid React or TypeScript on the frontend will go a long way.If you've ever wanted to work in a small, scrappy team with the energy of an early-stage startup but without the typical early-stage uncertainty, this is that opportunity.Ready to be part of the challenge? ðAbout the team ðOur Engineering team is the engine behind Factorial, crafting the tech that makes HR simple, fast, and reliable for thousands of companies.

If you love solving hard problems and want to build something that truly matters, come build it with us.We're a team of 200+ Product Engineers building Business Management solution that actually works for the people using it.

Our core stack is Ruby on Rails and React but the interesting work right now is what we're building on top of that: agentic workflows, LLM-integrated features, systems that behave probabilistically rather than deterministically.What are we looking for?You have an entrepreneurial mindset and genuinely enjoy the early stage of building something from scratch.You've shipped AI-powered features and know that evaluating them in production is the hard part, not building them.

You think about reliability and user friction before model complexity.You're comfortable reviewing agentic workflows and have opinions about LLM architecture tradeoffs.

Not just theoretical ones.You treat AI features as hypotheses.

Build, deploy, measure, adjust.

You own that whole loop, not just the build part.You can break down non-deterministic outputs into something the rest of the team can reason about and act on.You’re comfortable working with Ruby on Rails & React and understand how to integrate AI models into scalable, cloud-native environments.You help teammates who are transitioning from deterministic to probabilistic thinking, not by lecturing, but by working through it together.4+ years in software engineering, with some track record (or serious curiosity) around shipping AI features.You can explain a complex technical decision in English to someone who doesn't write code clearly, without condescension.What You’ll be Doing?You will be a Founding Engineer, taking ownership of big initiatives, and being interested in the outcome, not just the output.

About the outcome, you’ll also work with your team members to establish goals and plan a quarterly roadmap, putting special attention to the technical needs of our domain.You will be involved in customer calls to learn about their pains & needs.You will review code daily and get feedback on your own code at every pull request, from all team members, including juniors.You will learn from the entire team, both on technical topics (performance, architecture…) and core skills, in an environment driven by engineering quality.

You will also mentor junior team members and help them learn from your experience.How We Work ð» (Barcelona Office)At Factorial, we believe the best products are built when people come together, in person to collaborate, challenge ideas, and move fast.

That’s why our Engineering Teams follows an office-first, flexible schedule.We work on-site several days a week, using that time to connect, align, and innovate as a team.

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