Principal, Software Engineer

Walmart Walmart · Retail · Sunnyvale, CA +1

Principal Software Engineer for Walmart's Digital Out of Home platform, focusing on backend systems including Kafka pipelines, real-time decisioning services, and measurement/attribution workflows. Responsibilities include setting technical direction, designing scalable architectures on Kubernetes, managing data decisions across SQL/NoSQL databases, and driving reliability at scale for over 4,000 stores.

What you'd actually do

  1. Set technical direction for core backend systems, including Kafka‑based ingestion pipelines, real‑time decisioning services, and measurement/attribution workflows.
  2. Design and evolve scalable service architectures running in Kubernetes, ensuring systems remain reliable, observable, and easy to operate as scale and complexity grow.
  3. Own foundational data decisions, including schema design, data flows, and access patterns across SQL and NoSQL stores that support both real‑time use cases and downstream analytics.
  4. Drive reliability and performance at scale, identifying and addressing failure modes in systems that operate continuously across 4,000+ retail locations.
  5. Lead architecture and design reviews, guiding teams through complex tradeoffs around latency, consistency, scalability, and operational risk.

Skills

Required

  • backend systems
  • distributed architectures
  • containerized backend services
  • Kubernetes
  • backend streaming systems
  • event-driven architectures
  • message-based architectures
  • SQL databases
  • NoSQL databases
  • data modeling
  • schema design
  • system design
  • performance optimization
  • reliability engineering
  • mentoring senior engineers
  • technical leadership

Nice to have

  • Kafka
  • real-time decisioning
  • attribution workflows
  • fault-tolerance
  • schema evolution
  • backward compatibility

What the JD emphasized

  • 10+ years of experience building and operating large‑scale, enterprise‑grade backend systems in production environments.
  • Strong background designing and working with distributed architectures, including systems that operate under real‑time, high‑availability, and fault‑tolerance constraints.
  • Hands‑on experience designing and developing containerized backend services, with production deployments on platforms such as Kubernetes.
  • Proven experience building and operating backend streaming systems, including event‑driven or message‑based architectures.
  • Deep experience with SQL and NoSQL databases, including: Data modeling and schema design, Choosing appropriate storage technologies based on access patterns and scale, Managing schema evolution, migrations, and backward compatibility, Designing for performance, consistency, and reliability
  • Demonstrated ability to mentor senior engineers, lead design discussions, and raise the overall technical bar across teams.