Senior Java Developer — Fiserv in NenaghWe are hiring a Senior Java Developer to join our engineering team at Fiserv in Nenagh. We build robust, scalable payment and financial software used by clients globally. As a senior engineer you will design and deliver high-quality services, mentor colleagues, and help shape technical directionWhat you'll DoDesign, build and maintain Java-based services and microservices using Spring (Boot, Cloud) and RESTful APIDeliver clean, well-tested code using TDD/BDD practices and automated CI/CD pipelineLead architecture and design discussions for scalability, performance and resilienceTroubleshoot production issues, perform performance tuning and implement monitoring/observabilityCollaborate closely with product owners, QA, DevOps and other engineering teams in an Agile environmentReview code, mentor mid/junior engineers, and promote best practices for security and software qualityContribute to technical roadmaps, continuous improvement and platform hardening effortWhat You'll Have5+ years hands-on Java development experience, with modern Java versions (Java 8+)Strong experience with Spring Framework (Spring Boot) and building microserviceProven experience with REST APIs, cloud-native architectures and container technologies (Docker; Kubernetes experience desirableSolid knowledge of relational databases (SQL) and familiarity with NoSQL storesExperience with CI/CD tools (Jenkins, GitLab CI, Azure DevOps or similar) and automated testing frameworks (JUnit, Mockito)Strong debugging, profiling and performance tuning skillsExperience working in Agile/Scrum teams and collaborating with cross-functional stakeholdersExcellent communication skills and ability to mentor othersBachelor's degree in Computer Science, Engineering or equivalent practical experienceNice to haveExperience in payments, banking or financial servicesFamiliarity with cloud platforms (AWS, Azure or GCP)Knowledge of message-driven architectures (Kafka, Rabbit MQ)Security and compliance awareness relevant to financial systemsExperience with observability tooling (Prometheus, Grafana, ELK)About us We are Partners in Possibility — progressive, engaged and straightforward. At Fiserv in Nenagh we deliver technology that helps clients and communities move forward. If you're motivated by solving hard problems and helping teams succeed, we want to hear from you