More in detail, UST is a multinational company based in North America, certified as a Top Employer and Great Place to Work company with over 35,000 employees worldwide and presence in more than 35 countries. We are leaders in digital technology services, providing large-scale technological solutions to some of the world's most renowned organizations. We are seeking a highly skilled Senior Java Developer with extensive experience building scalable, high-performance distributed systems.

You will join a talented engineering team responsible for designing, developing, and evolving mission-critical applications using modern Java, cloud-native architectures, and event-driven technologies. ⚙ Design, develop, and maintain robust backend services using Java 17/21 and Spring Boot. Develop and maintain gRPC APIs and Protobuf schemas, ensuring backward compatibility and proper schema evolution. Work with Kafka-based event-driven architectures and production-scale data stores.

Create and maintain automated testing suites, including unit, integration, and contract tests. Participate in troubleshooting, root cause analysis, and postmortem activities. Contribute to CI/CD pipelines, cloud infrastructure, and containerized deployments. 8+ years of professional experience with Java development. ~3+ years of hands-on experience with Java 17 or Java 21, including modern language features such as records, sealed classes, pattern matching,



and virtual threads when applicable. ~ Strong expertise in Spring Framework and Spring Boot in production environments. ~ Proven experience with reactive programming using Project Reactor or RxJava (Mono, Flux, backpressure, retry strategies, hot vs.

Solid testing practices using JUnit 5, Mockito, and AssertJ. ~ Experience developing integration tests against real dependencies and contract/parity testing. ~ Strong knowledge of Kafka consumer and producer semantics. ~ Redis, PostgreSQL, or MongoDB. ~ Cloud experience with AWS (or equivalent cloud platforms), including services such as S3, IAM, managed Kafka solutions, and container runtimes. ~ English level C1 or higher. Knowledge of container packaging and multi-architecture image builds (Linux/AMD64 and Linux/ARM64). Python knowledge with the ability to read, understand, and debug existing code.

Experience working with Apache Arrow or other columnar data formats. CI/CD pipeline ownership using TeamCity, GitHub Actions, or similar technologies. Numerous benefits (Health Care Plan, Internet Connectivity, Life and Accident Insurances). ~ Adaptable Compensation Program: meals, kindergarten, transport, online English lessons, health care plan, and more. ~ Free access to several training platforms. ~ Real Work-Life Balance measures (flexibility, remote work policy, summer schedule, and more). ~

📌 Senior Java Developer (AWS/RxJava) (Ibiza)
🏢 UST España u0026 Latam
📍 Ibiza