Senior Software Engineer, Backend (ML Feature Platform)

Affirm is reinventing credit to make it more honest and friendly. The ML Feature Platform team builds a self-serve platform that powers feature development and serving for machine learning and decisioning across the company. As a Senior Backend Engineer, you'll own critical infrastructure that directly enables MLEs, analysts, and decisioning teams to create, explore, and serve data—making your work essential to Affirm's availability and performance.

About the Role

You'll lead the design and delivery of backend systems for feature creation, exploration, and serving infrastructure. This includes owning data storage, availability, visibility, and offline backfilling platforms that support end-to-end ML workflows. Your work will directly impact how Affirm's ML and online decisioning systems function, requiring you to balance performance, reliability, and developer experience.

Responsibilities

• Own and deliver quarterly goals for your team, leading engineers through ambiguous, open-ended problems
• Design and develop highly available distributed backend systems that support feature platform operations at scale
• Collaborate with product management, design, and analytics teams to articulate technical constraints and drive decisions that balance risks and trade-offs
• Proactively identify and advocate for process, technology, and business improvements; lead solutions to critical issues
• Establish and monitor operational metrics for your team's systems; participate in on-call rotations and support availability goals
• Set and raise code review and design standards across your team and beyond through technical leadership and communication
• Develop talent on your team through feedback, guidance, and modeling ownership and quality

Requirements

• 4+ years designing, developing, and launching backend systems at scale using Python, Kotlin, or similar languages
• Proven track record building highly available distributed systems using AWS, MySQL, Kubernetes, or equivalent technologies
• Experience defining and improving system architecture, reliability, and performance in production environments
• Demonstrated ability to lead teams, influence cross-functional stakeholders, and drive technical decisions

Benefits

Remote position based in Canada.