Senior Software Engineer – API Fraud Platform

About the role

Mastercard is looking for a Senior Software Engineer to join its Dublin engineering team building a real‑time decisioning platform for fraud detection. You will work on a high‑performance, distributed, in‑memory caching layer that processes mission‑critical transactions at global scale.

Key responsibilities

• Own end‑to‑end delivery of complex features, from architecture and design through testing, deployment and documentation.
• Design and implement high‑performance, scalable, secure Java APIs using advanced design patterns.
• Debug and troubleshoot multi‑tiered systems, including core, heap and thread‑dump analysis.
• Lead code reviews, design discussions and adoption of coding standards across the team.
• Coordinate releases in a follow‑the‑sun, multi‑region model, handling scope tracking and cross‑team sign‑offs.
• Participate in on‑call support, incident management, root‑cause analysis and performance improvement.
• Engage with product and business stakeholders to prioritize work and demonstrate new capabilities.

Required profile

• Senior‑level Java developer with strong experience in distributed systems and low‑latency services.
• Proven ability to take full ownership of features and mentor team members.
• Comfortable working in an Agile, collaborative environment.
• Strong problem‑solving skills and a focus on reliability and resiliency.

Required skills

• Java
• Distributed systems design
• In‑memory data caching
• API development and design patterns
• Performance optimization and low‑latency engineering
• Debugging (heap, thread dumps) and incident management