Java Backend Developer

Position: Java Backend Developer Client: Walmart Location: Sunnyvale, CA (On-site / Hybrid) Engagement Type: ContractAbout The RoleWalmart's Global Tech hub in Sunnyvale, CA is looking for a talented Java Backend Developer to design and build robust, scalable backend systems that power one of the world's largest retail ecosystems. You will work alongside world-class engineers to architect and deliver high-throughput, fault-tolerant services that handle massive transaction volumes across Walmart's digital and in-store platforms.Key Responsibilities Design, develop, and maintain high-performance Java-based backend services and microservices for enterprise-scale applications. Architect and implement RESTful APIs consumed by web, mobile, and internal service clients. Apply strong knowledge of data structures and algorithms to solve complex engineering problems efficiently. Lead and participate in system design discussions, translating business requirements into scalable, maintainable technical solutions. Build and manage microservices architectures using frameworks such as Spring Boot and Spring Cloud. Ensure high availability, fault tolerance, and performance optimization across distributed systems. Conduct thorough code reviews, mentor junior developers, and uphold engineering best practices. Collaborate with frontend teams, data engineers, DevOps, and product managers in an Agile environment. Contribute to CI/CD pipeline improvements, automated testing, and deployment strategies. Monitor system health, diagnose bottlenecks, and implement proactive performance tuning. Required Skills & Experience 9 years of professional backend development experience with strong expertise in Java (Java 11+). Deep understanding of Data Structures and Algorithms — ability to design and analyze solutions for time and space complexity. Strong System Design skills — experience designing large-scale distributed systems, including caching strategies, load balancing, database sharding, and message queuing. Hands-on experience building and deploying Microservices — service discovery, circuit breakers, API gateways, and event-driven communication. Proficiency designing and consuming REST APIs — versioning, authentication (OAuth2/JWT), rate limiting, and documentation (Swagger/OpenAPI). Experience with Spring Boot, Spring MVC, Spring Security, and related frameworks. Strong working knowledge of relational databases (MySQL, PostgreSQL) and NoSQL databases (Cassandra, MongoDB, or Redis). Familiarity with messaging platforms such as Kafka or RabbitMQ. Proficiency with Git, Maven/Gradle, and standard SDLC tooling. Experience with containerization using Docker and orchestration via Kubernetes. Preferred / Nice-to-Have Skills Experience working with cloud platforms — AWS, GCP, or Azure — in a production environment. Familiarity with GraphQL or gRPC as alternatives to REST. Exposure to large-scale retail, e-commerce, or fintech backend systems. Knowledge of observability tooling — Prometheus, Grafana, Splunk, or Datadog. Experience with infrastructure-as-code tools such as Terraform or Helm. Understanding of security best practices in distributed systems. Educational Qualifications Bachelor's or Master's degree in Computer Science, Software Engineering, or a related field, or equivalent hands-on experience.