Senior Software Engineer, Backend (Merchant Advocacy)

📋 Description

• Design and expand the backbone of our platform to scale to hundreds of thousands of merchants from all around the world
• Design and align the scope of work with other teams to deliver cross-team projects
• Mentor other engineers to ensure their development and growth
• Partner with Engineering Manager and Team Lead to drive and execute the long-term vision of the team
• Execute technical strategy for broad or complex requirements with forward-looking approaches that go beyond the direct team and solve large open-ended problems
• Utilize agentic development tools like Claude Code to automate parts of the development process

🎯 Requirements

• 5+ years of experience as a backend software engineer
• A strong understanding of Domain-Driven Design, distributed systems, and how architectural decisions affect performance and maintainability
• Proficiency with data models, API design (HTTP and RPC), state machines, event-driven architecture, and database design
• Excellent communication skills, both written and verbal. Must be proficient in asynchronous communication—written tech specs, ADRs, project plans, etc.
• Experience designing, developing, and launching backend systems (our stack: AWS, gRPC, Snowflake, Kotlin, Python, MySQL, Kubernetes). Java and Kotlin experience are especially helpful.
• Prior experience with monitoring and alerting systems (sentry.io, rollbar, chronosphere, kibana)

🎁 Benefits

• Health care coverage - Affirm covers all premiums for all levels of coverage for you and your dependents
• Flexible Spending Wallets - generous stipends for spending on Technology, Food, various Lifestyle needs, and family forming expenses
• Time off - competitive vacation and holiday schedules allowing you to take time off to rest and recharge
• ESPP - An employee stock purchase plan enabling you to buy shares of Affirm at a discount