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 10/26/2026full-timeRemote • CanadaSenior💰 CA$153,000 - CA$213,000 per yearWebsite

Core Competencies

Role fit

Core Competencies

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Demonstrates expertise in designing and developing scalable backend systems, with a strong focus on AI workloads and infrastructure. Proficient in mentoring engineers and establishing best practices in coding, design, and operational health.

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 StandardsHigh-Quality Code ProductionTechnical Planning

Soft Skills

Strong Communication SkillsMentoring Ability

Tools & Technologies

MySQLKubernetesAWSAI ToolsLLM Gateways

Certifications & Qualifications

Bachelor’s Degree in Related Field

Industry Keywords

AI WorkloadsOperational HealthMonitoring and AlertingAgentic WorkloadsGovernable AI Spend

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 spend
Partner with security, infrastructure, and product engineering teams to establish 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 for 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, including inference APIs, LLM gateways, 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 produce high-quality, understandable code
Proficiency making significant changes in a large codebase safely
Strong verbal and written communication skills
Equivalent practical experience or a Bachelor’s degree in a related field
Must reside in Alberta, British Columbia, Manitoba, New Brunswick, Newfoundland and Labrador, Nova Scotia, Ontario, Prince Edward Island, or Saskatchewan

Benefits

Comp & perks

Equity rewards may be included in the total compensation package
Monthly stipends for health, wellness, and tech spending
100% subsidized medical coverage for employees and dependents
Dental and vision coverage for employees and dependents
Remote-first work with flexibility within the country of employment
Flexible time off
Generous holiday calendars
Employee stock purchase plan (ESPP) to buy Affirm stock at a discount
Inclusive interview process and accommodations for candidates with disabilities
In-person onboarding experience for all new hires