Senior Software Engineer, Backend – AI Platform

Affirm

. Plan, execute, and own technical decisions and projects within the AI Platform team from design through launch and on-call .

Posted 10/30/2026full-timeRemote • United StatesSenior💰 $173,000 - $233,000 per yearWebsite

Core Competencies

Role fit

Core Competencies

Use this summary to align your resume positioning with the role.

Demonstrates expertise in designing and developing scalable backend systems, utilizing Python or Kotlin, and implementing AI frameworks and tools. Proven ability to mentor engineers and enhance coding practices while ensuring operational health and system reliability.

Highest-signal resume keywords

Backend System DesignPython ProgrammingAWS ExperienceKubernetes ProficiencyAI Frameworks Knowledge

ATS Keywords

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Applicant Tracking System Keywords

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Hard Skills

Backend DevelopmentDistributed SystemsCode Review StandardsReusable Code WritingSystem Metrics Monitoring

Soft Skills

Strong Communication SkillsMentoring Ability

Tools & Technologies

AWSMySQLKubernetesInference APIsLLM Gateways

Certifications & Qualifications

Bachelor’s Degree in Related Field

Industry Keywords

AI WorkloadsOperational HealthTechnical PlansAgentic WorkloadsFailover Controls

Tech Stack

Tools & technologies

AWSDistributed SystemsKotlinKubernetesMySQLPython

About the role

Key responsibilities & impact

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 scaling AI workloads across millions of users and transactions
Build identity, quota, routing, caching, and failover controls for attributable and governable AI spending
Partner with security, infrastructure, and product engineering teams on guardrails for agentic workloads and tool-access identity
Create and monitor system metrics and own operational health, including monitoring, alerting, runbooks, and on-call
Set and improve code review and design standards through writing and tech talks
Use AI tools and agentic workflows in coding, design review, and operations
Educate, mentor, and grow engineers while driving design, coding, and testing best practices

Requirements

What you’ll need

4+ years of experience designing, developing, and launching backend systems at scale
Experience using languages such as Python or Kotlin
Track record developing highly available distributed systems
Experience with AWS, MySQL, and Kubernetes
Practical production experience with LLMs, agents, or AI frameworks
Experience with inference APIs, LLM gateways such as LiteLLM, MCP, tool calling, evals, or agent runtimes
Understanding of AI usage and infrastructure for AI workloads
Experience defining technical plans for significant features or system components
Ability to write high-quality, understandable, and reusable code
Proficiency making significant changes in large codebases safely
Strong verbal and written communication skills
Equivalent practical experience or a Bachelor’s degree in a related field

Benefits

Comp & perks

Equity rewards may be included in total compensation
Monthly stipends for health, wellness, and tech spending
100% subsidized medical coverage for employees and dependents
Dental and vision coverage for employees and dependents
Flexible time off
Generous holiday calendars
Employee stock purchase plan (ESPP) with discounted Affirm stock
Remote-first flexibility
In-person onboarding experience
Inclusive interview process and disability accommodations