Senior Backend Engineer, AI Platform (Remote)

Affirm, Inc.; Philadelphia (Philadelphia County); Remote; USD 173,000 - 233,000; Full time

Benefits offered by this job

Health coverage for you and dependents

Tech setup stipends

Flexible time off

Employee stock purchase plan

Job summary

Affim is hiring for an AI Platform backend engineer to design, build, and operate scalable gateway, runtime, and evaluation services for AI workloads. You will own projects end-to-end, collaborating with security, infra, and product teams to enable safe, observable, and efficient deployments across millions of users.

You’ll mentor teammates, drive engineering standards, and leverage AI-native workflows to improve code quality and delivery speed while growing your own expertise in a remote-first

Qualifications

• 4+ years of experience designing, developing and launching backend systems at scale using languages like Python or Kotlin.
• Experience building highly available distributed systems with AWS, MySQL, and Kubernetes.
• Hands-on experience with LLMs, agents, or AI frameworks in production.

Responsibilities

• Plan, execute, and own technical decisions and projects within the AI Platform team from design through launch and on-call.
• Design and build gateway, runtime, and evaluation services for scalable AI workloads across millions of users.
• Make AI spend attributable and governable with identity, quota, routing, caching, and failover controls.
• Partner with security, infra, and product teams to set guardrails for agentic workloads.
• Create and monitor metrics and own the operational health of your systems.
• Set and improve code review and design standards and advocate for them beyond your team.
• Use AI tools and agentic workflows to multiply your own output and push for impact.
• Educate, mentor, and grow engineers, driving best practices in design, coding and testing.

Skills

Backend systems design

Python or Kotlin

Distributed systems

Code review & design standards

Communication skills

Mentoring

Ownership & initiative

Education

Bachelor's degree or equivalent

Tools

AWS

MySQL

Kubernetes

LLMs/Agents/AI frameworks

Job description

Affim is hiring for an AI Platform backend engineer to design, build, and operate scalable gateway, runtime, and evaluation services for AI workloads. You will own projects end-to-end, collaborating with security, infra, and product teams to enable safe, observable, and efficient deployments across millions of users.

You’ll mentor teammates, drive engineering standards, and leverage AI-native workflows to improve code quality and delivery speed while growing your own expertise in a remote-first