Senior Software Engineer

Summary

Join Affirm's Fraud Engineering organization as a Senior Software Engineer and contribute to building the foundational software that enables Affirm to respond strategically to fraud. You will own and deliver quarterly goals, lead engineers, design and implement backend services and APIs using Python or Kotlin, and collaborate with stakeholders across various teams. You will shape the team's roadmap, drive execution across projects, elevate quality standards, and represent the team in cross-functional initiatives. Proactive identification of opportunities to improve system reliability and team efficiency is crucial, as is contributing to operational excellence. Foster a culture of ownership, inclusion, and craftsmanship by mentoring teammates and upholding high code and design standards. This fully remote role is based in Europe and requires close collaboration with North American teams.

Requirements

• 5+ years of experience building backend systems at scale using Python or Kotlin
• Experience with distributed systems and infrastructure using AWS, MySQL/PostgreSQL, and Kubernetes
• Strong system design skills and a track record of delivering maintainable, extensible services
• Proficiency in SQL and working with data-rich environments
• Familiarity with CI/CD practices and safe production deployments
• Strong written and verbal communication skills, especially in distributed teams
• A proactive, ownership-driven mindset with a focus on learning and team success

Responsibilities

• You will be responsible for owning and delivering quarterly goals for your team, leading engineers through ambiguity to solve open-ended problems, and ensuring that everyone is supported throughout delivery
• You will design and implement backend services and APIs using Python or Kotlin, operating within Affirm’s microservice and event-driven architecture
• You will take an active role in shaping the team’s roadmap, collaborating on technical design, and driving execution across projects that span multiple teams
• You will partner with the Engineering Manager and your teammates to elevate quality standards, evolve engineering processes, and represent the team in cross-functional initiatives
• You will collaborate cross-functionally with stakeholders in Fraud Ops, Compliance, Product, Machine Learning, and Analytics to build scalable fraud tooling and infrastructure
• You will proactively identify opportunities to improve system reliability, team efficiency, or architecture—and lead efforts to address them
• You will contribute to operational excellence by maintaining high observability standards, responding to incidents, and participating in the on-call rotation
• You will foster a culture of ownership, inclusion, and craftsmanship by mentoring teammates, providing feedback, and upholding high code and design standards

Preferred Qualifications

• Experience with Snowflake, dbt, Airflow, or Chronosphere
• Background in fraud prevention, risk systems, or post-transaction tooling
• Experience working in the fintech sector or other highly regulated environments, with a strong understanding of risk, compliance, and operational constraints

Benefits

• 100% subsidized medical coverage, dental and vision for you and your dependents
• Equity rewards offered by Affirm Holdings, Inc
• Flexible Spending Wallets for tech, food and lifestyle
• Away Days - wellness days to take off work and recharge
• Learning & Development programs
• Parental benefits
• Employee Resource & Community Groups
• Creative tax benefits
• Health care coverage - Affirm covers all premiums for all levels of coverage for you and your dependents
• Flexible Spending Wallets - generous stipends for spending on Technology, Food, various Lifestyle needs, and family forming expenses
• Time off - competitive vacation and holiday schedules allowing you to take time off to rest and recharge
• ESPP - An employee stock purchase plan enabling you to buy shares of Affirm at a discount