AI Engineer - API & Integrations Team

Product AI Engineer

Hello! Do 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 Are obsessed with building and shipping fast Care about real impact, not hierarchy or titles If that sounds like you, keep reading.

The API & Integrations team addresses particular challenges  sit at the intersection between product and platform. We own product surface while we also design developer experiences for internal and external developers of integrations. We build tools for Factorial product teams to publish in our extensive public API. We build an integrations framework to achieve the best user experience and developer experience when using integrations.

Several Factorial products are already using this framework. And we keep expanding it. We enable our developer partners to extend Factorial and live the best developer experience. With the acquisition of Yep Code, we will be boosting how we build integrations, placing AI at the center of the process. Our mission is not only to unblock markets that rely on a fragmented market of different external software (payroll software solutions, ERPs, cloud-based identity services, etc.),

but also to lower the barrier so that anybody (even HR managers) is able to create new integrations.

As a Product AI Engineer at Factorial, you'll help define and build the next generation of our AI-native product using modern AI development practices. You will:

• Build product using Spec Driven Development
• Design and implement AI Skills
• Develop and maintain evaluation frameworks (Evals)
• Apply Retrieval-Augmented Generation (RAG)
• Design human-in-the-loop and agentic workflows
• Own systems end-to-end
• Stay close to our customers
• Collaborate closely with Product and Design
• Share knowledge and raise the bar

Who This Is For Your title matters less than your mindset. You might be mid, senior, or staff. What we care about is: AI as a habit: you've built real AI-powered systems or workflows (not just experiments) Proven impact: shipped projects, side projects, or contributions that made a measurable difference Product-first thinking: you design complete experiences, not just isolated components Speed & adaptability: you experiment, learn, and iterate fast Bonus points if you've worked with: LLMs, skill-based agents, MCP, or other AI protocols Technical Foundation (Not Strict Requirements) Strong candidates often have:
Solid software engineering fundamentals (any language — backend, frontend, ML) Experience shipping real products to production Knowledge of APIs, cloud platforms, and system design A fast learning curve with new tools and technologies

We care far more about what you've built than the stack you used.

How We Work Office-first in A Coruña, with 20% remote flexibility A people-first, high-trust culture built on radical candor and ownership A multicultural team (40+ nationalities) building the next generation of business management software

About us At Factorial, we're building the leading business management software for companies of all sizes. Our platform centralizes key workflows across HR, finance, and operations, freeing teams from manual processes so they can focus on what really matters: leading, growing, and taking care of their people. With over 1,200 employees across 7 markets, we serve 700,000+ users and are one of Europe's fastest-growing SaaS companies, backed by top-tier investors and proudly headquartered in Barcelona.

We believe in bold goals, radical ownership, and inclusive collaboration. If you're excited to shape the future of business management technology, we'd love to meet you.

Our Values We own it:
We take responsibility for every project. We make decisions, not excuses. We learn and teach:
We're dedicated to learning something new every day and, above all, share it. We partner:
Every decision is a team decision. We trust each other. We grow fast:
We act fast. We think that the worst mistake is not learning from them. We believe in diverse talent:
We welcome applicants from all backgrounds and strongly encourage people of diverse experiences and identities to apply. We believe in inclusion:
We are committed to equal opportunities and actively promote workplace inclusion of people with disabilities.

Perks of being part of our team We care about people and we also offer a lot of benefits for employees:
High growth, multicultural and friendly environment Alan as private health insurance Healthy life with Wellhub (Gyms, pools, outdoor classes) ‍ Save expenses with Cobee Language classes ‍ Breakfast in the office and organic fruit Nora discounts Free caffeine and theine Pet Friendly