Senior Software Engineer, Backend (Reliability Platform)

Affirm is reinventing credit to make it more honest and friendly, giving consumers the flexibility to buy now and pay later without any hidden fees or compounding interest. We're seeking a Senior Software Engineer to design and build a next-generation reliability platform that helps Affirm's production systems stay healthy, debuggable, and continuously improving. This hands-on role combines distributed systems engineering with AI-assisted development in a fast-paced environment that values both rapid iteration and high reliability standards.

About the Role

You'll own quarterly goals for your team while leading engineers through ambiguous, open-ended problems in platform reliability. This is a creative position that balances "vibe coding"—rapid iteration and shipping—with rigorous standards for reliability, quality, and maintainability across production infrastructure.

Responsibilities

• Own and deliver quarterly goals for your team; guide engineers through complex, open-ended reliability challenges
• Collaborate with product management, design, and analytics on ideation, technical constraints, and risk-aware decision-making
• Proactively identify and advocate for solutions to project, process, technology, and business issues
• Support operations and availability of your team's artifacts through metrics, monitoring, and on-call participation
• Establish and elevate code review and design standards across your team and beyond through documentation and technical talks
• Develop talent on your team through feedback, guidance, and example-setting

Requirements

• 4+ years of experience as a software engineer
• Experience designing, developing, and launching backend systems at scale using Python, Kotlin, AWS, MySQL, and Kubernetes
• Experience shipping web applications with declarative UI frameworks (React or Vue)
• Practical experience using LLMs or AI frameworks to enhance automation with guardrails and citations
• Ability to define technical plans for significant features or system components with elegant, simple, and extensible designs
• Track record of writing high-quality code that is easily understood and used by others
• Proficiency making significant changes in large codebases and developing tools and practices to do so effectively

Location & Work Arrangement

Remote, US-based