Affirm

Senior Software Engineer, Backend (AI Platform)

Affirm
Apply
2 hours ago
Remote, CanadaSenior

Responsibilities

  • Own technical decisions and projects from design through launch and on-call operation.
  • Design and build scalable gateway, runtime, evaluation, and observability services for AI workloads.
  • Develop identity, quota, routing, caching, failover, cost attribution, and governance controls.
  • Partner with security, infrastructure, and product engineering teams on agentic-workload guardrails and tool-access identity.
  • Create system metrics, monitoring, alerting, runbooks, and operational health practices.
  • Improve code review and design standards, communicate through technical writing and talks, and mentor engineers.

Requirements

  • 4+ years of experience designing, developing, and launching backend systems at scale.
  • Experience building highly available distributed systems with technologies such as Python or Kotlin, AWS, MySQL, and Kubernetes.
  • Production experience with LLMs, agents, AI frameworks, inference APIs, LLM gateways, MCP, tool calling, evaluations, or agent runtimes.
  • Experience defining technical plans and delivering significant, elegant, simple, and extensible system components.
  • Ability to make significant changes safely in large codebases and write high-quality, understandable code.
  • Strong collaboration, verbal communication, written communication, ownership, and feedback-seeking skills.
  • Bachelor’s degree in a related field or equivalent practical experience.

Benefits

  • Remote-first work arrangement, limited to candidates residing in specified Canadian provinces, with occasional in-person work and an in-person onboarding experience.
  • 100% subsidized medical, dental, and vision coverage for employees and dependents.
  • Monthly technology, health, and wellness spending stipends.
  • Flexible time off and generous holiday calendars.
  • Employee stock purchase plan with discounted Affirm stock.
  • Inclusive interview accommodations for candidates with disabilities.
Affirm

About Affirm

1,001-5,000 employees

Affirm provides buy now, pay later installment financing at online and in-store checkout, along with a consumer app and virtual card, for shoppers and merchants. It monetizes through merchant fees and interest on select loans, with no late fees. Founded in 2012 and headquartered in San Francisco, Affirm is a public company listed on NASDAQ that powers payments for thousands of ecommerce retailers.

Contact me