Principal Software Engineer

The Impact of a Principal Software Engineer at Coupa: We're looking for someone who's rebuilt a production system while it was running. CSP (Coupa Supplier Platform) serves millions of supplier companies-it's where they find work, receive orders, issue invoices, and get paid. The platform started as a Rails monolith. It works, but it needs to evolve. More traffic, more features, multi-cloud deployment, higher availability requirements. You'll report to the VP of Engineering. CSP operates as a nimble team outside the larger engineering org, moving fast and pioneering approaches that demonstrate what's possible. You'll work with Ruby on Rails, Golang, Java-and introduce whatever else the architecture needs. What You'll Do • Lead the architectural evolution. Traffic is growing, functionality is expanding, robustness matters more than ever. You'll define what changes, in what order, and why. • Set the patterns: API design, microservice boundaries, deployment pipelines, monitoring, reliability. Make them real, not theoretical. • Mentor engineers. Guide decisions. Review architecture and code. Build the kind of team that ships ambitious work. • Join the Architectural Steering Group. Share what you learn with Principal Engineers across Coupa. Import what works elsewhere. • Partner with SRE on cloud-native infrastructure: CI/CD, containers, infrastructure-as-code, multi-cloud capabilities. • Own security, multi-tenancy isolation, data governance, and compliance across all regions. • Work with product, design, and business teams to turn supplier workflows into systems that scale. What You Will Bring to Coupa • 15+ years building B2B SaaS at scale. You've held leadership and architectural roles where your decisions stuck around. • Real experience evolving legacy systems into microservices-in production, with users depending on uptime. • Deep knowledge of API-driven services, multi-tenant architectures, and B2B integration patterns that handle millions of users. • Solid foundation in modern deployment: CI/CD, Docker/Kubernetes, infrastructure-as-code, working with cloud providers like AWS or GCP. • Comfort across technology stacks (Rails, Golang, Java) and the judgment to pick tools that solve problems, not resume lines. • Track record mentoring teams-providing direction without micromanaging, staying technical without bottlenecking. • Problem-solving skills that balance scale, performance, technical debt, and shipping features. You know the trade-offs because you've lived them. • Communication skills that work across engineering, product, and business. You build consensus without watering down hard truths.