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We create honest financial products that improve lives.
Senior Software Engineer, Back-end – Fraud
Location
Poland
Posted
126 days ago
Salary
zł301K - zł401K / year
Seniority
Senior
Job Description
Senior Software Engineer, Back-end – Fraud
Affirm
• 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. • On-Call Rotation - There would be an on-call rotation for this role as a requirement.
Job 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.
- Experience with Snowflake, dbt, Airflow, or Chronosphere (nice to have)
- Background in fraud prevention, risk systems, or post-transaction tooling. (nice to have)
- Experience working in the fintech sector or other highly regulated environments, with a strong understanding of risk, compliance, and operational constraints. (nice to have)
Benefits
- 100% subsidized medical coverage, dental and vision for you and your dependents
- 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
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