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
Were looking for Staff 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 Team
The Operations domain sits at the core of Factorial. This is where we build the systems that run the day-to-day reality of work for thousands of companies systems that must be accurate compliant and reliable.
Our teams own business-critical workflows such as:
- How employee time is tracked planned and managed
- How the employee journey is modeled from onboarding to offboarding
- How companies represent their organizational structure
- How compensation and payroll data are calculated and trusted.
- Our mission is to turn operational complexity into simple AI-powered experiences helping companies run smoothly at scale while keeping humans in control of what matters most.
What youll do as a Staff Engineer in AI
Define how we build AI at scale
Drive the evolution of modern AI development practices across the organization. Youll help establish how we design build evaluate and operate AI-native product experiences ensuring they are reliable compliant and aligned with business outcomes.
Lead Spec-Driven Development for AI
Promote a culture of defining clear specifications before shipping including expected behaviours constraints risk boundaries and measurable success criteria. Youll guide teams in using these specs to iterate safely and efficiently with the most powerful LLMs.
Build reusable AI foundations
Design and implement shared AI capabilities and abstractions that can be adopted across multiple product domains. Youll focus on creating scalable secure and well-governed systems rather than isolated features.
Design and evolve AI Skills
Drive the creation of modular reusable AI skills that can automate real workflows and take safe auditable actions within Factorials ecosystem especially in finance-critical contexts.
Establish robust evaluation frameworks
Lead the development of automated and human-in-the-loop evaluation systems to measure quality correctness safety and reliability. Youll help teams move from experimentation to production-grade AI.
Shape Retrieval-Augmented Generation strategies
Define how we ground AI systems in trusted company and customer data. Youll balance probabilistic models with deterministic sources of truth ensuring scalability compliance and accuracy.
Design human-in-the-loop and agentic workflows
Architect systems that combine LLMs rules and user oversight. Youll enable automation while ensuring transparency control and regulatory alignment in critical business processes.
Own systems end-to-end
Lead initiatives from problem definition and system design to production rollout monitoring and continuous improvement. Youll focus on long-term maintainability and organizational leverage.
Stay deeply connected to customers
Promote a strong customer-centric engineering culture. Youll engage with customers directly to understand real workflows risks and constraints ensuring we solve meaningful problems.
Partner with Product Design and Leadership
Collaborate cross-functionally to embed AI into core product experiences. Youll influence roadmap decisions and ensure AI is integrated as a fundamental part of workflows.
Raise the bar across the company
Mentor engineers contribute to hiring and technical growth and define best practices that elevate Factorials engineering culture and AI maturity.
Who This Is For
For people who care about:
- AI as a habit: youve 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.
Strong Staff Engineers at Factorial have:
- Very solid software engineering expertise in both backend and frontend.
- Experience with cloud platforms such as AWS Azure or Google Cloud Platform.
- Experience shipping real products to production.
- Knowledge of APIs cloud platforms and system design
- Are seen as leaders technically and culturally maintaining high-quality standards.
- Challenge engineering processes from hiring to code deployment.
- Drive adoption of new abstractions creating supporting ecosystems like documentation and metrics.
- Lead key technical decisions and creates company-wide abstractions.
- Excellent communication skills in English; knowledge of other languages is a plus specially Spanish.
We care far more about which initiatives youve led and products youve built than the stack you used.
How We Work
- Office-first in Barcelona & Madrid 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.
At Factorial were 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 over 1200 employees across 7 markets we serve 700000 users and are one of Europes fastest-growing SaaS companies backed by top-tier investors and proudly headquartered in believe in bold goals radical ownership and inclusive collaboration. If youre excited to shape the future of business management technology wed love to meet you.
Our Values
- We own it: We take responsibility for every project. We make decisions not excuses.
- We learn and teach: Were 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. 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.
Wanna learn more about us Check our website!
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 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
The hiring process
If you apply heres what to expect:
- A first conversation with our Talent Acquisition Partner. It will be about comparing our expectations and making sure we match on a human level. We will also check our Engineering Rubrics (check them out they are open!) and the salary in your position.
- A second conversation with the teams Engineering Manager. This is about making sure we can work together. Here you will have a conversation about the team their needs your profile and how can you complement it. Expect to have a mix of a human and technical conversation.
A Live Engineering Challenge with two Factorial engineers: At Factorial were passionate about hiring engineers who can think clearly communicate well leverage the best tools and learn very this challenge were not looking for a finished product but for how you structur...
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 growWere looking for Staff Engineers who:Treat AI as central to their craft Are obsessed with building and shipping fastCare about real imp...
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
Were looking for Staff 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 Team
The Operations domain sits at the core of Factorial. This is where we build the systems that run the day-to-day reality of work for thousands of companies systems that must be accurate compliant and reliable.
Our teams own business-critical workflows such as:
- How employee time is tracked planned and managed
- How the employee journey is modeled from onboarding to offboarding
- How companies represent their organizational structure
- How compensation and payroll data are calculated and trusted.
- Our mission is to turn operational complexity into simple AI-powered experiences helping companies run smoothly at scale while keeping humans in control of what matters most.
What youll do as a Staff Engineer in AI
Define how we build AI at scale
Drive the evolution of modern AI development practices across the organization. Youll help establish how we design build evaluate and operate AI-native product experiences ensuring they are reliable compliant and aligned with business outcomes.
Lead Spec-Driven Development for AI
Promote a culture of defining clear specifications before shipping including expected behaviours constraints risk boundaries and measurable success criteria. Youll guide teams in using these specs to iterate safely and efficiently with the most powerful LLMs.
Build reusable AI foundations
Design and implement shared AI capabilities and abstractions that can be adopted across multiple product domains. Youll focus on creating scalable secure and well-governed systems rather than isolated features.
Design and evolve AI Skills
Drive the creation of modular reusable AI skills that can automate real workflows and take safe auditable actions within Factorials ecosystem especially in finance-critical contexts.
Establish robust evaluation frameworks
Lead the development of automated and human-in-the-loop evaluation systems to measure quality correctness safety and reliability. Youll help teams move from experimentation to production-grade AI.
Shape Retrieval-Augmented Generation strategies
Define how we ground AI systems in trusted company and customer data. Youll balance probabilistic models with deterministic sources of truth ensuring scalability compliance and accuracy.
Design human-in-the-loop and agentic workflows
Architect systems that combine LLMs rules and user oversight. Youll enable automation while ensuring transparency control and regulatory alignment in critical business processes.
Own systems end-to-end
Lead initiatives from problem definition and system design to production rollout monitoring and continuous improvement. Youll focus on long-term maintainability and organizational leverage.
Stay deeply connected to customers
Promote a strong customer-centric engineering culture. Youll engage with customers directly to understand real workflows risks and constraints ensuring we solve meaningful problems.
Partner with Product Design and Leadership
Collaborate cross-functionally to embed AI into core product experiences. Youll influence roadmap decisions and ensure AI is integrated as a fundamental part of workflows.
Raise the bar across the company
Mentor engineers contribute to hiring and technical growth and define best practices that elevate Factorials engineering culture and AI maturity.
Who This Is For
For people who care about:
- AI as a habit: youve 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.
Strong Staff Engineers at Factorial have:
- Very solid software engineering expertise in both backend and frontend.
- Experience with cloud platforms such as AWS Azure or Google Cloud Platform.
- Experience shipping real products to production.
- Knowledge of APIs cloud platforms and system design
- Are seen as leaders technically and culturally maintaining high-quality standards.
- Challenge engineering processes from hiring to code deployment.
- Drive adoption of new abstractions creating supporting ecosystems like documentation and metrics.
- Lead key technical decisions and creates company-wide abstractions.
- Excellent communication skills in English; knowledge of other languages is a plus specially Spanish.
We care far more about which initiatives youve led and products youve built than the stack you used.
How We Work
- Office-first in Barcelona & Madrid 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.
At Factorial were 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 over 1200 employees across 7 markets we serve 700000 users and are one of Europes fastest-growing SaaS companies backed by top-tier investors and proudly headquartered in believe in bold goals radical ownership and inclusive collaboration. If youre excited to shape the future of business management technology wed love to meet you.
Our Values
- We own it: We take responsibility for every project. We make decisions not excuses.
- We learn and teach: Were 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. 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.
Wanna learn more about us Check our website!
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 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
The hiring process
If you apply heres what to expect:
- A first conversation with our Talent Acquisition Partner. It will be about comparing our expectations and making sure we match on a human level. We will also check our Engineering Rubrics (check them out they are open!) and the salary in your position.
- A second conversation with the teams Engineering Manager. This is about making sure we can work together. Here you will have a conversation about the team their needs your profile and how can you complement it. Expect to have a mix of a human and technical conversation.
A Live Engineering Challenge with two Factorial engineers: At Factorial were passionate about hiring engineers who can think clearly communicate well leverage the best tools and learn very this challenge were not looking for a finished product but for how you structur...
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