Senior Software Engineer, Backend (Identity International)

About the Role

Affirm's Identity team handles mission-critical decisions in the customer checkout experience across all markets outside North America. As a Senior Software Engineer on the Identity International backend team, you'll own technical strategy and execution for KYC (know-your-customer), user lifecycle management, and identity decisioning across multiple regulatory environments. This role combines hands-on engineering with technical leadership—you'll spend most of your time writing code while also shaping quarterly direction, mentoring engineers, and driving cross-team collaboration.

Responsibilities

• Own and deliver quarterly technical goals for the Identity International platform, translating ambiguous business and compliance requirements into reliable, well-architected solutions
• Design systems across service boundaries, identifying tradeoffs in performance, availability, and scale; advocate for technical investments that improve long-term execution and reduce operational toil
• Write production code in Kotlin and Python, investigate complex production issues, and maintain high standards for code quality, testing, and operational health
• Lead engineers through technical ambiguity, mentor team members, support new hires and interns, and contribute to hiring and onboarding
• Collaborate with product management, design, analytics, and partner teams to ensure technical solutions align with customer needs and regulatory compliance across diverse markets
• Build playbooks, documentation, and processes that improve team velocity and system reliability

Requirements

• Senior-level backend engineering experience with proven ability to own complex systems end-to-end
• Strong proficiency in Kotlin, Python, or similar backend languages
• Experience designing and operating distributed systems at scale
• Demonstrated ability to lead technical discussions, mentor engineers, and influence roadmaps across team boundaries
• Comfortable working in regulated environments or with compliance-heavy product domains (fintech, identity, KYC experience a plus)
• Track record of improving code quality, operational standards, and team processes

Location & Work Arrangement

Remote, based in Spain. The Identity International team is distributed across Spain and Poland.