Senior Software Engineer (Java and React)

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 (Java and React)

Mastercard is a global technology leader in the payments industry, connecting and powering a digital, inclusive economy that benefits everyone, everywhere. We focus on making transactions safe, simple, smart, and accessible. With innovation fueled by secure data, powerful networks, and strong partnerships, Mastercard enables individuals, businesses, governments, and financial institutions to realize their full potential.
At the heart of our culture is our Decency Quotient (DQ)—a guiding principle that influences how we work, collaborate, and deliver value to the world. Operating in over 210 countries and territories, we are committed to building a more sustainable world that unlocks priceless possibilities for all.
Empowering Small Businesses
Mastercard plays a pivotal role in supporting Small and Medium Enterprises (SMEs)—a vital segment that drives local and global economies. We aim to be the trusted network helping SMEs grow and thrive by offering valuable, accessible solutions through our B2B customers and partners. SMEs rely on Mastercard to accept global payments and manage their businesses effectively—from cash flow to operational efficiency.
The SME Engineering organization is dedicated to building innovative, competitive solutions tailored to SME needs. We focus on lean, high-impact teams that solve complex technical problems using cutting-edge tools and technologies, such as:
Cloud-native services (AWS/Azure)
GraphQL APIs
High-throughput SQL, key-value, and document data stores
Microservices architecture
Integration with Mastercard’s core tech stack
We emphasize agile development, regular brainstorming, and collaborative learning across experience levels. Our values—Create Value, Grow Together, Move Fast—are rooted in integrity, inclusion, and a commitment to doing the right thing.
The Role: Senior Software Engineer (SME Products – Dublin)
As a Senior Software Engineer, you will contribute to products in domains including Merchant Profile & Identity Management, Accounts Payable/Receivable, and Virtual Card Solutions for SMEs. You’ll be part of a high-performing team delivering impactful software solutions from conception to production.
Key Responsibilities
Analyze, design, develop, and deliver scalable software solutions
Participate in planning, estimation, and prioritization with product and business stakeholders
Take ownership of full delivery lifecycle: design, development, testing, deployment, documentation, and operations
Automate build, deployment, and operational processes
Engage in code and design trade-offs to make optimal technical decisions
Integrate services with a focus on seamless customer experiences
Conduct demos and acceptance reviews with product owners
Improve operational metrics and end-user experience
Mentor and support junior team members
Promote best practices in coding, testing, and design
Drive reuse, standardization, and innovation across teams and guilds
Required Technical Skills & Experience
Languages & Secure Coding: Proficiency in Java, Springboot and React with strong knowledge of secure coding standards (OWASP, CWE, etc.)
Systems Knowledge: Understanding of operating systems (Linux/Windows), multithreading, and performance tuning
Debugging & Troubleshooting: Ability to analyze dumps and identify performance or logic issues
Version Control & CI/CD: Expertise in Git (e.g., Gitflow), CI/CD tools (Jenkins, Azure Pipelines), and deployment automation
API Design & Integration: Experience building scalable APIs and integrating with service-oriented architectures
Testing Practices: Hands-on with TDD, BDD, contract testing, regression, and performance testing (Test Pyramid)
Architecture & Patterns: Knowledge of advanced design patterns (MVC, dependency injection, lazy loading, etc.)
DevOps & Monitoring: Familiarity with tools like Sonar, Checkmarx, Zally for code quality and security scanning
Agile Delivery: Skilled in story pointing, velocity tracking, and driving definition-of-done
Non-Functional Requirements: Understands how to capture and implement security, scalability, performance, and regulatory needs
Customer Journey Awareness: Commitment to ensuring robust systems with high availability (99.95%) and low incident mitigation times (MTTM)
What You’ll Bring
Strong collaboration skills to work across engineering and business stakeholders
A proactive attitude with a drive to continuously improve processes and systems
Passion for mentoring and fostering team knowledge sharing
Dedication to delivering quality software that positively impacts SME customers

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.