Senior Software Engineer - Finance Services (Fintech)

Location: Barcelona, Spain; office-first in Barcelona and Madrid with 20% remote flexibility

Company

Factorial builds business management software that centralizes HR, finance, and operations workflows for companies of all sizes.

What you will do

• Lead the backend architecture of internal sales, invoicing, and billing applications.
• Design and maintain resilient backend workflows for critical financial data.
• Integrate global payment platforms and APIs such as Stripe and Adyen.
• Develop end-to-end products in collaboration with design and product teams.
• Use AI assistants and automation tools to accelerate development and build smart agents.
• Drive agile practices through pull request reviews, continuous deployment, and collaborative specifications.

Requirements

• 5+ years of professional experience as a Backend or Software Engineer.
• Strong foundation in database management, Docker containers, and modern cloud infrastructure architecture.
• Experience building reliable, secure, production-ready APIs with concurrency handling, data integrity, and system monitoring.
• Product-first mindset and understanding of how software impacts customers and business outcomes.
• Comfort working with Agile methodologies, peer reviews, and cross-functional teams.

Nice to have

• Background in fintech, payment platforms, or financial applications.
• Experience developing or integrating AI agents.

Culture & Benefits

• People-first, high-trust culture focused on ownership, learning, partnership, and inclusion.
• Multicultural environment with more than 40 nationalities.
• Private health insurance through Alan.
• Wellhub access, employee discounts, language classes, office breakfast, fruit, and refreshments.
• Pet-friendly workplace.

Hiring process

• Conversation with a Talent Acquisition Partner.
• Conversation with the Engineering Manager followed by a live engineering challenge with two engineers.
• Final coffee chat with the CTO; the process is conducted remotely by videoconference.