Senior Software Engineer - C# OR Java

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 - C# OR Java

About Mastercard Open Finance

Mastercard Open Finance is transforming the account‑to‑account payments ecosystem. We deliver secure, scalable connectivity to over 3,000 financial institutions in 20 global markets, empowering users with control over their financial data and enabling trusted connections between financial institutions and third‑party providers. Our platform fuels innovation across payments while safeguarding security and privacy at scale.

The Role

We’re looking for a Senior Software Engineer to join our Connectivity division - the team that ensures our platform integrates flawlessly with thousands of bank and financial institutions APIs. You’ll tackle reliability at scale, low latency, and regulatory complexity, working in a flat, collaborative team where engineers own features end‑to‑end.

What You'll Work On

• Design, develop, and maintain APIs and integration modules connecting our platform to thousands of European banks and financial institutions.
• Collaborate with engineers and product stakeholders to define requirements, set acceptance criteria, and deliver solutions.
• Contribute to architecture by ensuring scalability, maintainability, and adherence to best practices.
• Maintain quality through code reviews, testing, and continuous improvement initiatives.
• Solve complex problems involving performance, distributed systems, and regulatory constraints.

Our Stack

• .NET 8
• Java
• Cloudagnostic microservices architecture

What We're Looking For

• Strong experience building backend services (preferably in .NET and Java).
• Experience working in fastpaced, productcentric environments.
• Solid understanding of API design, distributed systems, cloud environments.
• Experience in establishing bank connections through PSD2 interfaces.
• Ability to write clean, maintainable, and testable code.
• Collaborative mindset and eagerness to work closely with product and engineering peers.
• Curiosity and drive to continuously improve systems, processes, and yourself.

Why Join Us

• Impact at scale: Touch millions of users through seamless financial institution integrations.
• Small team, big responsibility: Lean environment where contributions matter daily.
• Cutting-edge fintech: Shape the future of open banking in one of Europe’s fastest-moving ecosystems.
• Join Mastercard Open Finance and help us elevate quality, drive innovation, and shape the future of open banking.

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.