Senior Software Engineer (API, Fraud Platform)

Join Mastercard as a Senior Software Engineer in Dublin, where you'll work on a high-performance, distributed, in-memory data caching layer that supports mission-critical transaction processing. This hands-on role involves end-to-end delivery, design and innovation, independent problem-solving, technical leadership, release and delivery coordination, operational excellence, stakeholder engagement, mentoring, and continuous improvement. You should have strong proficiency in modern Java, experience with distributed systems, and a passion for Agile ways of working.

Responsibilities

• End-to-end delivery of complex features and services across the full software development lifecycle, including architecture, design, development, testing, deployment, rollback planning, and documentation.
• Design and implement high-performance, scalable, and secure Java capabilities; apply advanced design patterns and API standards; produce high- and low-level design documentation.
• 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.
• Understanding of secure development practices (secure-by-design) and awareness of PCI-DSS considerations for handling payment card data

Requirements

• 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
• Shows initiative, takes on challenging opportunities, and demonstrates end-to-end ownership
• Strong proficiency with modern Java (JDK 17 or later); distributed systems and multi-threading experience
• Expertise in JUnit or equivalent automated testing frameworks; designing test plans across unit, regression, performance and integration
• Experience with Spring, Spring Boot, Hibernate, RESTful APIs, JSON; application servers (e.g. JBoss/Tomcat); Shell scripting
• Solid experience with Linux, SQL and message-queuing systems, and with design patterns
• Excellent written and verbal communication and strong cross-team, cross-geography collaboration
• Passionate about Agile ways of working (SAFe / SCRUM), code quality and engineering best practices
• Bachelor's degree in Computer Science, Information Technology or equivalent work experience
• Driven, highly motivated, strong team player. Fluency in English

Preferred

• Experience with distributed caching or in-memory data grid technologies (e.g. Apache Geode, Hazelcast, Redis, Coherence) is highly desirable