Staff Software Engineer, Backend (Cost Engineering)

Affirm is reinventing credit to make it more honest and friendly, giving consumers the flexibility to buy now and pay later without hidden fees or compounding interest. We're hiring a Staff Software Engineer, Backend (Cost Engineering) to lead our cloud cost visibility and optimization efforts across AWS, multi-cloud, and AI/LLM infrastructure. This is a remote role based in Canada.

About the Role

Engineering owns cost visibility and optimization across Affirm's cloud and AI infrastructure. You'll operate at the intersection of finance, infrastructure, and data engineering—designing tooling, automation, and processes that scale cost governance across a fast-growing multi-cloud and multi-AI-vendor footprint. You'll set technical direction for the team, influence cost strategy with infrastructure and platform leaders, and turn ambiguous "why did spend spike" questions into durable systems and self-service tooling. We treat cost anomalies with the same rigor as production incidents, using a severity framework with defined detection sources, TTD/TTR metrics, and escalation paths.

Responsibilities

• Set technical strategy for your team on a year-long timescale and connect it to critical, business-impacting projects
• Collaborate across product development, product management, design, and analytics to ensure technical sustainability and manage risks and trade-offs
• Act as a force-multiplier for your team by defining and advocating for technical solutions and operational processes
• Own your team's operations and availability by establishing monitoring, triage rotations, playbooks, policies, testing, and alerting to support on-call efforts
• Foster a culture of quality and ownership by setting code review and design standards, and advocating for them through writing and tech talks
• Develop talent on your team through feedback, guidance, and leading by example

Requirements

• 8+ years of experience designing, developing, and launching backend systems at scale using languages such as Python or Kotlin
• Extensive track record of designing and operating large-scale, mission-critical systems
• Experience with cloud infrastructure (AWS preferred) and cost optimization or FinOps practices
• Ability to influence technical strategy across cross-functional teams
• Strong communication and mentorship skills

Benefits

Competitive compensation, health insurance, 401(k) matching, professional development opportunities, and remote work flexibility.