Staff Software Engineer, Backend (Capacity Modeling)

RemoteLeadPosted Aug 17, 2026

PythonKotlinAWSKubernetesSparkMySQLDynamoDBRedis+13 more

About this role

Affirm's Capacity Modeling team ensures the platform can handle forecasted traffic during peak sales events by building statistical models that translate demand forecasts into concrete capacity plans. You'll set technical strategy for infrastructure scaling across compute, caching, and databases.

Must have

You have 8+ years of experience designing, developing and launching backend systems at scale using languages like Python or Kotlin

You have an extensive track record of developing highly available distributed systems using technologies like AWS, MySQL, Spark and Kubernetes

You have experience supporting scale up and down of large scale sales event such as Prime Day, Black Friday Cyber Monday, or other sales holidays

You have tuned autoscaling, CPU/Memory, and multi-threading for compute type workloads

You have experience delivering major features, system components or deprecating existing functionality through a technical and execution plan

You thrive in ambiguity, and are comfortable moving from low level language idioms to architecture of large systems

Your growth and impact trajectory demonstrates mastery of gathering and iterating on feedback from engineering and cross-functional peers

You have strong verbal and written communication skills for effective collaboration with global engineering team

Technologies

PythonAWSSparkKotlinGitDockerRESTLinuxPostgreSQLMySQLTerraformMicroservicesRedisGrafanaPrometheusDynamoDBKubernetesDatadogCI/CDAuroraDBElasticCache

Responsibilities

You will be responsible for setting technical strategy for your team on a year-long time scale

You will collaborate across teams in the product development lifecycle with product management, design and analytics

You will act as a force-multiplier for your team through definition and advocacy of technical solutions and operational processes

You take ownership of your team's operations and availability with monitoring, triage rotations, playbooks, policies, testing and alerting

You will foster a culture of quality and ownership by setting code review and design standards and advocating through writing and tech talks

You will help develop talent on your team by providing feedback and guidance, and leading by example

Benefits

Health insuranceDental insuranceVision insuranceEmployee share purchase planWellness allowanceHome office allowanceParental leaveFlexible vacation timeCompetitive salaryStock options

Amenities

Health care coverage with all premiums covered for all levels for you and your dependentsFlexible Spending Wallets with generous stipends for Technology, Food, Lifestyle needs, and family forming expensesCompetitive vacation and holiday schedules allowing time off to rest and rechargeESPP enabling purchase of Affirm shares at a discountReasonable accommodations provided to candidates with disabilities during hiring process