Senior Platform Engineer

ABOUT KOJO It's time to build. Whether it's creating more housing, upgrading our infrastructure, or adapting to climate change, one thing is clear: the construction industry is at the center of solving our biggest problems. We’re making buildings cheaper and easier to build by transforming the way commercial construction companies buy their materials. Join us. Founded in 2018, Kojo is now one of the fastest-growing construction technology companies in the world. Construction accounts for $10 trillion in global spend annually and we can’t live without its output - our roads, schools, hospitals, and offices. Despite this, there’s been very little innovation over the past 70 years in how materials - which constitute up to 40% of project costs - are bought and sold. This is our opportunity. We're looking for an amazing Senior Platform Engineer who will build the tooling, golden paths, and self-service abstractions that let our product teams move fast - not just operate clusters, but engineer the infrastructure layer itself. About the Role This is a platform engineer, not a traditional SRE. We want a strong software engineer who specializes in infrastructure - someone who builds tooling, golden paths, and self-service abstractions for product teams, not just someone who operates clusters. Hard software engineering skills are the bar; infra and SRE depth is how that bar gets applied. This role will include: - IaC repos: typed component resources, factories, multi-env stacks (Pulumi, Terraform) - The EKS platform: Karpenter autoscaling, and GitOps delivery via ArgoCD, Kargo, and Helm - CI/CD pipelines (GitHub Actions) and release automation - Developer-experience tooling and AI-driven development workflows (skills, hooks, MCP servers, managed agents) - Observability, network and edge security, and SOC 1 + SOC 2 evidence automations Our Stack - AWS + EKS - Pulumi (TypeScript) + Terraform - Kubernetes - ArgoCD + Kargo + Helm GitOps - Aurora PostgreSQL + Prisma + Slonik - DynamoDB - EventBridge + SQS - OpenTelemetry + Datadog About You A strong, infrastructure-minded software engineer will thrive in this role! If you're excited about building developer platforms, AI-driven workflows, and rock-solid cloud infrastructure, apply with us! What you’ve accomplished: - Strong AWS services knowledge - Strong in JavaScript, TypeScript, and Node - Solid grasp of parallel programming - Deep PostgreSQL and ORM optimization skills (Prisma, Slonik, etc.) - Hands-on with NoSQL databases (Redis, DynamoDB, Elasticsearch, etc.) - Strong system design and microservice architecture (event-driven, idempotent consumers, fanout, etc.) - Experience with message brokers - Comfortable with infrastructure as code, any tool works (Terraform, Pulumi, AWS CDK, or similar) - Experience building RESTful APIs - Production Kubernetes experience, ideally EKS (Karpenter, VPC CNI with NetworkPolicy, managed node groups, multi-cluster) - Familiarity with observability standards and tooling, vendor-agnostic (OpenTelemetry, any APM platform) - Network segmentation know-how (VPCs, subnetting, security groups, firewall config, DNS, etc.) - Edge and network security (CloudFront, WAF, ACM certificates, on top of VPC segmentation) - Pipeline configuration, ideally GitHub Actions - Strong in AI-driven development (Claude, Codex, Cursor, or similar) and fluent in its building blocks: skills, hooks, custom commands, managed agents, etc. Nice to have: - GraphQL or gRPC - GitOps with ArgoCD, Kargo, and Helm - Certifications (AWS, CNCF, Linux Foundation, etc.) - Security tooling (SAST, Software Composition Analysis, IAST, SIEM, threat management) and compliance frameworks like SOC 1 and SOC 2 - SRE and reliability practices (SLOs, error budgets, incident response, runbooks, on-call) - FinOps and cost management (cost allocation on EKS, right-sizing, Savings Plans) - Compliance automation (SOC 2 evidence, IAM Identity Center and permission sets, least-privilege access) What you care abo…