Senior Software Engineer, Backend (Fintech)

TL;DR

Senior Software Engineer, Backend (Fintech): Building and optimizing a foundational merchant data platform with an accent on high availability, latency SLAs, and scalable data pipelines. Focus on designing distributed systems, managing merchant identity, and improving risk and fraud detection capabilities.

Location: Must be based in Spain (Visa sponsorship available)

Salary: €86,000 - €122,000

Company

Affirm is a fintech company reinventing credit to provide honest and friendly buy-now-pay-later solutions without hidden fees.

What you will do

• Own and deliver quarterly goals for the Merchant Data Platform team, leading engineers through ambiguity.
• Design and launch high-availability backend systems and distributed architectures.
• Collaborate with product management, design, and analytics to define technical constraints and trade-offs.
• Mentor junior engineers to improve their designs, code quality, and testing practices.
• Manage system reliability and performance, including metric monitoring and on-call rotation.
• Identify and solve complex process, technology, or business issues proactively.

Requirements

• 4+ years of experience as a software engineer with leadership and mentoring experience.
• Proficiency in Python or Kotlin.
• Experience with AWS, MySQL, and Kubernetes in large-scale distributed systems.
• Expertise in synthesizing complex business requirements into high-quality system designs.
• Must be based in Spain.
• Strong verbal and written communication skills for global collaboration.

Culture & Benefits

• 100% subsidized medical, dental, and vision coverage for employees and dependents.
• Equity rewards (RSUs) and an Employee Stock Purchase Plan (ESPP).
• Flexible spending wallets for technology, food, and lifestyle needs.
• Wellness "Away Days" to recharge and take time off.
• Comprehensive parental benefits and Learning & Development programs.