Senior Backend Engineer, AI Platform (Remote)

Affirm, Inc.; Baltimore (MD); Remote; USD 173,000 - 233,000; Full time

Benefits offered by this job

Health coverage for employees and your

Monthly tech stipends for setup

Flexible time off

Employee stock purchase plan (ESPP)

Job summary

Affirm, Inc. is hiring for an experienced backend engineer to design, develop, and deploy large-scale distributed systems for an AI Platform. You will build gateways and runtimes that securely scale to millions of users and transactions while enabling model governance and tool integrations.

You will collaborate with security, infra, and product teams, set guardrails for agent workloads, and drive high-quality code and design standards across a global engineering group. Remote-friendly in the US.

Qualifications

• 4+ years designing, developing and launching backend systems at scale.
• Experience with AWS, MySQL, Kubernetes in production.
• Practical experience with LLMs, agents, or AI frameworks.
• Ability to define technical plans for large features or systems.
• Strong code quality and maintainability skills.
• Ownership mindset and proactive feedback seeking.
• Excellent written and verbal communication for global teams.
• Bachelor’s degree or equivalent practical experience.

Responsibilities

• Plan, execute, and own technical decisions within the AI Platform team from design through launch and on-call.
• Design and build the gateway, runtime, and evaluation services handling AI workloads at scale.
• Make AI spend attributable and governable with identity, quota, routing, and caching controls.
• Collaborate with security, infra, and product teams to set guardrails for agent workloads and identity models.
• Create and monitor metrics; own the operational health of deployed systems.
• Set and improve code review and design standards across the team.
• Leverage AI tools and agentic workflows to boost productivity and impact.
• Educate, mentor, and grow engineers; promote best practices in design, coding, testing.

Skills

Backend systems design

Distributed systems

Python

Kotlin

AWS

MySQL

Kubernetes

LLMs

Agent runtimes

Education

Bachelor's degree in a related field

Tools

LiteLLM

MCP Gateway

LLM Gateway

Job description

Affirm, Inc. is hiring for an experienced backend engineer to design, develop, and deploy large-scale distributed systems for an AI Platform. You will build gateways and runtimes that securely scale to millions of users and transactions while enabling model governance and tool integrations.

You will collaborate with security, infra, and product teams, set guardrails for agent workloads, and drive high-quality code and design standards across a global engineering group. Remote-friendly in the US.