Senior Software Engineer (API) – Fraud Platform

Our Purpose Mastercard powers economies and empowers people in 200+ countries and territories worldwide. Together with our customers, we’re helping build a sustainable economy where everyone can prosper. We support a wide range of digital payments choices, making transactions secure, simple, smart and accessible. Our technology and innovation, partnerships and networks combine to deliver a unique set of products and services that help people, businesses and governments realize their greatest potential. Title and Summary Senior Software Engineer (API) – Fraud Platform SENIOR SOFTWARE ENGINEER (JAVA) — DATA CACHING / DISTRIBUTED SYSTEMS Location: Dublin, Ireland OVERVIEW We are hiring a Senior Java Software Engineer to join a Dublin-based engineering team working on Mastercard's real-time decisioning platform. The team designs, builds and operates a high-performance, distributed, in-memory data caching layer that supports mission-critical transaction processing at global scale, with a strong focus on low latency, high availability and resiliency. This is a hands-on senior role for an engineer who enjoys working close to complex distributed systems, owning features end-to-end, and helping shape technical direction within a collaborative Agile team. • Want to work on industry-leading, mission-critical distributed systems at global scale? • Motivated by solving complex performance, resiliency and data-consistency problems? • Keen to take end-to-end ownership and mentor others in a high-trust team? ROLE & KEY RESPONSIBILITIES As a Senior Software Engineer, you will act as a technical owner and leader within the team: • End-to-end delivery — Own complex features and services across the full software development lifecycle: architecture, design, development, testing, deployment, rollback planning and documentation. • Design & innovation — Design and implement high-performance, scalable and secure Java capabilities; apply advanced design patterns and API standards; produce high- and low-level design documentation to a professional standard. • Independent problem-solving — Drive solutions for complex problems; debug and troubleshoot across multi-tiered systems, including core, heap and thread-dump analysis; design resilient solutions. • Technical leadership & influence — Lead code, design and process trade-off discussions; drive adoption of coding standards and frameworks; review code, tests and automation produced by other team members. • Release & delivery coordination — Support coordinated releases across a follow-the-sun, multi-region engineering model, including scope tracking, cross-team sign-offs and release execution. • Operational excellence — Participate in on-call support; lead incident management, root-cause analysis and remediation; proactively improve performance and stability metrics. • Stakeholder engagement — Contribute to prioritisation with Product and Business stakeholders; lead demos and acceptance discussions with Product Owners; report status and manage risks in owned service areas. • Mentoring & knowledge sharing — Mentor less-experienced engineers, deliver knowledge-transfer and brown-bag sessions, and help build shared understanding across the team. • Continuous improvement — Identify inefficiencies and drive automation of build, operate and run activities; research and evaluate emerging technologies and frameworks. REQUIRED SKILLS & EXPERIENCE • Strong proficiency with modern Java (JDK 17 or later); distributed systems and multi-threading experience. • Experience with Spring, Spring Boot, Hibernate, RESTful APIs, JSON; application servers (e.g. JBoss/Tomcat); Shell scripting. • Experience with distributed caching or in-memory data grid technologies (e.g. Apache Geode, Hazelcast, Redis, Coherence) is highly desirable. • Solid experience with Linux, SQL and message-queuing systems, and with design patterns. • Expertise in JUnit or equivalent automated testing frameworks; designing test plans across unit, regression, performance and integration. • CI/CD proficiency — tools such as Jenkins and Maven; source control in a multi-developer, distributed environment. • Familiarity with observability and monitoring tooling for alerting, dashboards and performance analysis. • Understanding of secure development practices (secure-by-design) and awareness of PCI-DSS considerations for handling payment card data. • Passionate about Agile ways of working (SAFe / SCRUM), code quality and engineering best practices. OTHER ATTRIBUTES • Excellent written and verbal communication and strong cross-team, cross-geography collaboration. • Shows initiative, takes on challenging opportunities, and demonstrates end-to-end ownership. • Driven, highly motivated, strong team player. Fluency in English. EDUCATION Bachelor's degree in Computer Science, Information Technology or equivalent work experience. Corporate Security Responsibility All activities involving access to Mastercard assets, information, and networks comes with an inherent risk to the organization and, therefore, it is expected that every person working for, or on behalf of, Mastercard is responsible for information security and must: Abide by Mastercard’s security policies and practices; Ensure the confidentiality and integrity of the information being accessed; Report any suspected information security violation or breach, and Complete all periodic mandatory security trainings in accordance with Mastercard’s guidelines.