Staff Software Engineer, Backend – Capacity Modeling

Affirm

Staff Software Engineer creating backend capacity models ensuring Affirm handles peak traffic efficiently. Collaborating across teams to set technical strategy and operational processes.

Posted 5/8/2026full-timeRemote • 🇨🇦 CanadaLead💰 CA$178,000 - CA$228,000 per yearWebsite

Tech Stack

Tools & technologies

AWSDistributed SystemsKotlinKubernetesMySQLPythonSpark

About the role

Key responsibilities & impact

Responsible for setting technical strategy for your team on a year-long time scale, and help your team tie it together with critical, business-impacting projects.
Collaborate across teams in the product development lifecycle by collaborating with product management, design & analytics to ensure technical sustainability, risks and trade-offs are well understood and managed.
Act as a force-multiplier for your team through your definition and advocacy of technical solutions and operational processes.
Take ownership of your team’s operations and availability by ensuring you have the right monitoring, triage rotations, playbooks, policies, testing and alerting in place to support “keep the lights on” & on-call efforts.
Foster a culture of quality and ownership on your team by setting code review and design standards for your team, and advocating for them beyond your team through your writing and tech talks.
Help develop talent on your team by providing feedback and guidance, and leading by example.

Requirements

What you’ll need

8+ years of experience designing, developing and launching backend systems at scale using languages like Python or Kotlin.
Extensive track record of developing highly available distributed systems using technologies like AWS, MySQL, Spark and Kubernetes.
Experience supporting scale up and down of large scale sales events such as Prime Day, Black Friday Cyber Monday, or other sales holidays.
Experience tuning autoscaling, CPU/Memory, and multi-threading for compute type workloads.
Experience delivering major features, system components or deprecating existing functionality in a system through the definition of a technical and execution plan.
Strong verbal and written communication skills that support effective collaboration with our global engineering team.

Benefits

Comp & perks

Health care coverage - Affirm covers all premiums for all levels of coverage for you and your dependents
Flexible Spending Wallets - generous stipends for spending on Technology, Food, various Lifestyle needs, and family forming expenses
Time off - competitive vacation and holiday schedules allowing you to take time off to rest and recharge
ESPP - An employee stock purchase plan enabling you to buy shares of Affirm at a discount

ATS Keywords

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Applicant Tracking System Keywords

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Hard Skills & Tools

PythonKotlinbackend systemsdistributed systemsautoscalingCPU tuningMemory tuningmulti-threadingtechnical execution plancode review

Soft Skills

collaborationcommunicationleadershipfeedbackguidanceownershipadvocacyculture of qualitytechnical strategyforce-multiplier