Senior Java Backend Developer – Reactive Systems & GenAI

Job Title: Senior Java Backend Developer – Reactive Systems & GenAI Job Type: W2 Contract Experience: 8+ Years (Preferred) Location: Austin, TX (Onsite) Job Summary We are looking for an experienced Senior Java Backend Developer with strong expertise in Advanced Java, Reactive Programming, Spring Boot, Spring WebFlux, Kafka, and NoSQL databases such as Couchbase and MongoDB. The ideal candidate should have hands-on experience designing and developing scalable, high-performance, event-driven and reactive applications. Experience with Generative AI (GenAI) and Claude Code for AI-assisted software development is highly desirable. Key Responsibilities Design, develop, and maintain scalable backend applications using Advanced Java and Spring Boot. Implement reactive and non-blocking applications using Spring WebFlux and Reactive Programming. Apply Java Functional Programming concepts, including Lambda Expressions, Streams API, and Functional Interfaces. Develop event-driven and distributed applications using Apache Kafka. Design and manage NoSQL database solutions using Couchbase and MongoDB. Develop and integrate web services using Spring Web Services and RESTful APIs. Implement reactive system architectures to support high-throughput and low-latency applications. Leverage GenAI tools and Claude Code to improve development productivity, code generation, debugging, and testing. Write unit tests and ensure code quality using JUnit, Mockito, and other testing frameworks. Collaborate with cross-functional teams to design, develop, troubleshoot, and optimize backend services. Follow best practices for clean code, performance optimization, security, and application scalability. Required Technical Skills Advanced Java: Strong knowledge of Core Java, Java 8+, Functional Programming, Lambda Expressions, Streams API, and Multithreading. Spring Boot & Spring WebFlux: Hands-on experience building reactive, non-blocking applications and microservices. Reactive Programming: Experience with Project Reactor, Mono, Flux, and reactive system design. Apache Kafka: Experience with event-driven architecture, producers, consumers, and messaging. Couchbase: Hands-on experience with Couchbase database, data modeling, queries, and integration with Java applications. MongoDB: Experience with NoSQL database design, queries, and application integration. Spring Web Services: Experience developing and consuming SOAP-based web services and service integrations. Unit Testing: Strong experience with JUnit, Mockito, and automated unit testing. Preferred / Good-to-Have Skills Experience with Generative AI (GenAI) and AI-assisted development tools. Hands-on experience with Claude Code. Experience building distributed and highly scalable reactive systems. Knowledge of microservices architecture and REST APIs. Experience with CI/CD pipelines and Agile development methodologies. Ideal Candidate Profile A strong Java backend engineer who has hands-on experience building reactive, event-driven microservices using Spring Boot, WebFlux, Kafka, and NoSQL databases, along with the ability to leverage modern GenAI development tools.