Senior Staff Software Engineer, Backend (Compute Platform)

Affirm is hiring a Senior Staff Software Engineer for its Compute Platform organization. The role leads the architecture, reliability, automation, and workload safety standards of Affirm’s EKS platform, while partnering with engineering teams and mentoring engineers.

Responsibilities:

• Architect and evolve Affirm's EKS platform, driving strategy across cluster lifecycle, node management, and shared cluster components
• Lead the technical direction for cluster provisioning, upgrades, and teardown through standardized IaC (Terraform, Spacelift) and self-service workflows
• Own the reliability of core shared components across the fleet (Karpenter, CoreDNS, VPC CNI, Kube Proxy, Metrics Server, etc) and the CI/CD pipeline that ships them consistently
• Define and enforce EKS workload safety standards covering resource configuration, workload isolation and blast radius, disruption tolerance (PDBs), Karpenter consolidation strategies, etc
• Build the enforcement and automation path that moves each standard from research and white-glove onboarding through broad adoption to policy-enforced defaults for new workloads
• Establish the observability, baseline audits, and reporting needed to identify hot spots and measure risk mitigation over time
• Partner with cluster-user teams (checkout, batch, ML, analytics, DevProd, etc) to understand workload needs and shape the platform accordingly
• Drive cost and capacity strategy across node scaling, bin packing, and EC2 instance selection
• Mentor engineers across the Compute Platform teams and set the bar for operational excellence
• Participate in the on-call rotation, triage and catalogue runtime K8s issues, and collaborate with SRE on production incidents

Requirements:

• Deep EKS and Kubernetes internals expertise, including cluster upgrades, node lifecycle, scheduling, and autoscaling (Karpenter, Cluster Autoscaler)
• Demonstrated experience automating Kubernetes operations at fleet scale, from cluster provisioning, upgrades, and node lifecycle to self-healing remediation and policy-driven enforcement, replacing manual toil with auditable, self-service workflows
• Strong grasp of workload reliability patterns: resource tuning, probes, PDBs, topology and isolation constraints
• Experience designing and enforcing platform standards through policy (admission control, OPA/Gatekeeper or equivalent) and automated frameworks
• Infrastructure as Code fluency with Terraform and a GitOps or pipeline-driven delivery model (ArgoCD, kube-applier, or similar)
• Observability instincts: defining SLOs, building metrics, logs, and alerting coverage, and running data-driven baseline audits
• Cross-functional collaboration skills with platform, product, SRE, and capacity teams
• Demonstrated mentorship and technical leadership across teams
• Drive to track emerging Kubernetes community best practices and adapt them to Affirm's needs
• 10+ years in software or infrastructure engineering with proven delivery of complex platform solutions
• 6+ years hands-on operating production Kubernetes at scale, ideally EKS on AWS
• Strong cloud-native architecture experience on AWS (EC2, VPC, IAM, EKS)
• Experience with Infrastructure-as-Code (Terraform, Spacelift a plus) and GitOps-style deployment pipelines
• Expert-level proficiency in Go or Python and a proven track record building production-grade Kubernetes controllers, operators, and platform tooling that other engineering teams depend on
• Track record designing and enforcing standards across many teams without becoming a bottleneck
• Exceptional problem-solving and systems-thinking skills
• Demonstrated leadership and cross-functional influence
• This position requires either equivalent practical experience or a Bachelor's degree in a related field