Principal Software Engineer – Marketplace Platforms

Team•Sunnyvale, CA

6h•Onsite

About The Position

We are seeking a Principal Software Engineer to lead the design and development of enterprise-scale Marketplace platforms supporting sellers, listings, pricing, orders, and real-time transactions. This role requires deep expertise in Java, distributed systems, event-driven architectures, Kafka, and Big Data ecosystems, with exposure to AI/ML-driven marketplace intelligence. Building the right technology foundation for Infrastructure & platforms is vital to success at the scale of Walmart. Our team builds and maintains the foundational technologies that support the tech organization. Included in this are data platforms, enterprise architecture, DevOps, cloud computing, and infrastructure. All of these products and services are supported by scalable and powerful infrastructure, ensuring a secure and seamless employee and customer experience across stores, digital channels, and distribution centers.

Requirements

10+ years of software engineering experience in large-scale systems.
Expert proficiency in Java with strong knowledge of concurrency and multithreading.
Deep experience building distributed, highly available systems.
Hands-on experience with Apache Kafka (topics, partitions, offsets, schema evolution, exactly-once semantics).
Experience with Big Data technologies: Spark (batch & structured streaming), Hadoop ecosystem (HDFS, Hive, YARN), Flink or equivalent stream-processing engines.
Strong experience with microservices, REST/gRPC APIs.
Proficiency with SQL and NoSQL databases (MySQL, PostgreSQL, Cassandra, MongoDB, etc.).
Strong system design, troubleshooting, and performance-optimization skills.
Bachelor's degree in computer science, computer engineering, computer information systems, software engineering, or related area and 5 years’ experience in software engineering or related area.
OR 7 years’ experience in software engineering or related area.

Nice To Haves

Marketplace, e-commerce, payments, or supply-chain platform experience.
Cloud-native development on AWS, GCP, or Azure.
Experience with Kubernetes, Docker, and service mesh.
Experience handling millions of sellers, SKUs, and transactions.
Familiarity with ML platforms, feature stores, or real-time inference.
Experience with observability tools (Prometheus, Grafana, ELK, OpenTelemetry).
Strong understanding of security, data governance, and compliance.
Master’s degree in computer science, computer engineering, computer information systems, software engineering, or related area and 3 years' experience in software engineering or related area.
Background in creating inclusive digital experiences, demonstrating knowledge in implementing Web Content Accessibility Guidelines (WCAG) 2.2 AA standards, assistive technologies, and integrating digital accessibility seamlessly.
Knowledge of accessibility best practices and joining us as we continue to create accessible products and services following Walmart’s accessibility standards and guidelines for supporting an inclusive culture.

Responsibilities

Serve as a technical authority responsible for building high-throughput, low-latency systems that power marketplace growth at massive scale.
Architect and build distributed marketplace services for seller onboarding, catalog, pricing, inventory, and order flows.
Design event-driven and streaming architectures using Apache Kafka for real-time marketplace signals.
Develop and optimize Java-based microservices using Spring / Spring Boot.
Build high-volume data pipelines using Big Data frameworks (Spark, Hadoop, Flink) for analytics and ML.
Enable AI/ML use cases such as fraud detection, pricing optimization, seller scoring, and recommendations.
Lead system design reviews, performance tuning, and scalability planning.
Define engineering standards for resiliency, observability, CI/CD, and operational excellence.
Mentor senior engineers and influence platform-wide architectural decisions.
Partner with product, data science, infrastructure, and security teams.

Benefits

Incentive awards for performance
401(k) match
Stock purchase plan
Paid maternity and parental leave
PTO
Multiple health plans
Competitive pay
Performance-based bonus awards
Medical coverage
Vision coverage
Dental coverage
Stock options
Company-paid life insurance
Parental leave
Family care leave
Bereavement leave
Jury duty leave
Voting leave
Short-term disability
Long-term disability
Company discounts
Military Leave Pay
Adoption and surrogacy expense reimbursement
PTO and/or PPTO that can be used for vacation, sick leave, holidays, or other purposes.
Walmart-paid education benefit program (Live better U) for full-time and part-time associates, covering high school completion to bachelor's degrees, including English Language Learning and short-form certificates. Tuition, books, and fees are completely paid for by Walmart.