Senior/Staff Software Engineer (Communications)

Hello!

We're starting something new at Factorial: Chats. It's a fresh area of the product, built around communication and, from day one, built with AI and agents doing real work in it, not just a chatbot bolted onto the side. There's no team page for this yet. No backlog gathering dust, no "how we've always done it." Just the problem, and whoever shows up to solve it.

We're hiring a Senior or Staff engineer to help get Chats off the ground. Fullstack is ideal, but if your expertise lies merely in mobile it works for us too!

This isn't just a new product, it's a chance to rethink how software gets built. We're creating an AI-native product from scratch, where AI isn't another feature but part of the core architecture and user experience. Every technical and product decision starts with the question: how would we build this if AI existed from day one?

We're looking for engineers with a founder mentality. People who thrive in ambiguity, move quickly, question assumptions, and are excited to create rather than maintain. There won't be years of legacy decisions to work around, only opportunities to shape the product, the platform, and the culture from the ground up.

About the team

Our 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.

More info about the Communications team here

What we're looking for?

Your title matters less than your mindset. You might be senior or staff, what we care about is:

• Builder mentality: You've built products from 0 before, in a startup or a similarly high-ambiguity environment, and you're energized by that rather than needing a defined roadmap.
• Adaptability: You're comfortable when priorities change quickly and requirements aren't fully defined yet.
• Technical range: Fullstack experience (Rails/React/React Native), or deep React Native expertise if you're mobile-focused.
• AI as a habit: You've built real AI- or agent-powered systems, not just experimented with them.
• Seniority: Solid experience as a software engineer, comfortable owning ambiguous problems end to end.
• Communication: Comfortable working in English in a multicultural team.

Bonus points if you've worked with LLMs, agent frameworks, MCP, or other AI protocols.

What You'll Be Doing?

• Build Chats from zero: from the first architecture decisions to features real customers use every day.
• Design and ship experiences with AI and agents at the core, not as an add-on, this is central to what Chats is.
• Work across the stack: Ruby on Rails on the backend, React on web, React Native on mobile or focus on mobile if that's your strength.
• Adapt fast: priorities, scope and direction will shift as we learn. This is a startup-within-the-company, and comfort with change matters more than a fixed playbook.
• Partner closely with product and design to define what Chats becomes, informed directly by customer feedback.
• Help shape the team itself: its practices, its bar for quality, and how it works day to day.

How We Work (Barcelona or Madrid 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 approach.

We work on-site several days a week, using that time to connect, align, and innovate as a team. However, we also understand the importance of focus and flexibility, so we support remote work when it makes sense - whether for deep work, personal needs, or just a change of scenery.

This balance helps us stay agile, creative, and closely connected, while giving everyone the space to do their best work.

At Factorial we don't evaluate you by years of experience but by your knowledge and skills.

We use our Career Path with a rubric framework where we define what is expected for each experience level and skill. This framework allows you to know your current level and what you need to keep growing. We love transparency, so our Career Path includes the salaries for each level, which we share during the first interview to ensure alignment.

Our Hiring Process

1. Intro Call → Chat with our Talent Partner about your journey and goals.
2. Hiring Manager Interview → Deep dive into your product mindset, teamwork, and problem-solving.
3. Live Challenge → A collaborative technical exercise based on real-life problems.
4. Final Coffee Chat → A relaxed conversation with our CTO & VP of Engineering to explore our vision, culture, and your growth.

The whole process is remote, using videoconferencing tools!

About Factorial

At Factorial, we’re building the leading AI Business Management Software for companies of all sizes. Our platform centralizes key workflows across HR, Finance, Talent, Operations, and IT, freeing teams from manual processes so they can focus on what really matters: leading, growing, and taking care of their people.With over 1,500 employees across Europe, Asia, Africa, and America. We are one of Europe’s fastest-growing SaaS companies, proudly headquartered in Barcelona. If you're excited to shape the future of business management technology, we’d love to meet you.

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. If you would like to learn more about our inclusive recruitment processes, you are welcome to indicate so optionally and we will share additional information with 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.

Wanna learn more about us? Check our website!

Perks of being part of Factorial

• 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
• Food discounts with Nora
• Pet Friendly
• Much more that we'll spill during the interview process!