Senior Software Engineer, Backend (Merchant & Partner Lifecycle)
Job Description
<div class="content-intro"><p>At Affirm, we exist for the moments that matter—giving people a clear, predictable way to pay over time, with no hidden fees, no surprises, and no tradeoffs on what matters most.</p></div><p>The Merchant & Partner Lifecycle (M&PL) team is at the forefront of Affirm’s architectural transformation. We are addressing critical architectural risks by consolidating merchant lifecycle orchestration into a newly cohesive domain. </p> <p> </p> <p>You will act as a technical leader responsible for building out the brand new lifecycle-orchestrator service that’s at the heart of multiple connected systems. Your work will deliver immediate availability improvements through system simplification and isolation, and modernize older parts of the codebase.</p> <p> </p> <p><strong>What You'll Do</strong></p> <ul> <li>Design & expand the backbone of our platform to scale to hundreds of thousands of merchants from all around the world</li> <li>Design and align the scope of work with other teams to deliver cross-team projects</li> <li>Mentor other engineers to ensure their development & growth</li> <li>Partner with Engineering Manager and Team Lead to drive and execute the long-term vision of the team</li> <li>Execute technical strategy for broad or complex requirements with insightful and forward-looking approaches that go beyond the direct team and solve large open-ended problems</li> <li>Utilize agentic development tools like Claude Code to automate parts of the development process</li> <li>Improve engineering standards, tooling, and processes throughout the organization</li> </ul> <p><strong>What We Look For</strong></p> <ul> <li>5+ years of experience as a backend software engineer</li> <li>A strong understanding of Domain-Driven Design, distributed systems, and how architectural decisions affect performance and maintainability</li> <li>Proficiency with data models, API design (http and RPC), state machines, event-driven architecture, and database design</li> <li>Excellent communication skills, both written and verbal. Must be proficient in asynchronous communication–written tech specs, ADRs, project plans, etc.</li> <li>Experience designing, developing, and launching backend systems (our stack: AWS, gRPC, Snowflake, Kotlin, Python, MySQL, Kubernetes). Java and Kotlin experience are especially helpful.</li> <li>Prior experience with monitoring and alerting systems (<a href="http://sentry.io/">sentry.io</a>, rollbar, chronosphere, kibana)</li> </ul> <p>This posting is for an existing vacancy.</p> <p><strong>Pay Grade - N<