Senior Software Engineer, Back-end

About the role

Join a European-based backend engineering team that builds and maintains systems critical to Affirm's repayment scheduling. You will contribute to a platform that manages billions of dollars in payments annually, directly impacting the financial well-being of millions. This is a chance to shape and operate large-scale systems in a fast-paced, agile environment.

Key facts

What you'll do

• Take ownership of quarterly team objectives, guiding engineers through complex, open-ended challenges.
• Collaborate with product management, design, and analytics to inform product development, identify technical limitations, and make informed decisions.
• Proactively identify and lead the resolution of issues related to projects, processes, technology, or business operations.
• Ensure the operational health and availability of team systems by creating and monitoring metrics and participating in on-call rotations.
• Champion a culture of quality and accountability by establishing and improving code review and design standards.
• Mentor and develop team members through feedback and leading by example.

Requirements

• Possess 4 or more years of experience in designing, developing, and launching backend systems at scale, using languages such as Python or Kotlin.
• Demonstrate a history of building highly available distributed systems utilizing technologies like AWS, MySQL, and Kubernetes.
• Have experience in defining technical plans for significant feature or system component delivery, emphasizing elegant, simple, and extensible designs.
• Write high-quality, understandable, and reusable code.
• Show proficiency in making substantial modifications within large codebases and have developed tools and practices to do so safely.
• Exhibit a proactive approach to personal growth, actively seeking feedback from colleagues and stakeholders.
• Possess strong verbal and written communication skills to facilitate effective collaboration with a global engineering team.

Nice to have

• Experience with financial systems or payment processing.
• Familiarity with event-driven architectures.

Skills & tools

• Python or Kotlin
• AWS
• MySQL
• Kubernetes

Practical notes

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Compensation: Base pay range of 308,000 zł - 428,000 zł per year.

• Equity: Grade 4.
• Benefits include monthly stipends for health, wellness, and tech spending, 100% subsidized medical coverage, dental, and vision for employees and dependents.
• Additional benefits: Flexible Spending Wallets (tech, food, lifestyle), Away Days, Learning & Development programs, Parental benefits, Employee Resource & Community Groups.
• Eligible for creative tax benefits, subject to applicable law and company policy.
• Affirm is a remote-first company.
• Reasonable accommodations will be provided to candidates with disabilities during the hiring process.

About the company

Affirm Holdings, Inc. is an American financial technology organization that operates as a point-of-sale lender. Max Levchin, a co-founder of PayPal, created the business in 2012. Today, it ranks as the largest buy now, pay later financing provider based in the United States. By 2025, the company reported nearly 27 million active users and handled $37 billion in total annual payment volume. The business provides unsecured installment loans right at the moment of purchase. Customers can access these financing options through payment links during online checkout, virtual cards, physical payment cards, and connected third-party digital wallets or banking mobile applications. Affirm earns revenue by charging merchant service fees, collecting interest from borrowers, or combining both methods. The company does not charge any late fees to its customers. In addition to point-of-sale financing, the company offers consumer savings accounts and a debit card. Loan underwriting decisions rely on machine learning systems that analyze traditional credit scores alongside other relevant transaction data. These financial services are available to consumers in the United States, Canada, and the United Kingdom. As an employer in the financial technology sector, the organization hires professionals to support its growing loan processing systems, banking integrations, and consumer products. Employees build technology that processes billions of dollars in transactions while maintaining transparent terms for buyers and sellers across three major international markets.