Senior Software Engineer

Join Mastercard as a Senior Software Engineer in Weldon Spring, Saint Charles County. This full-time position offers the opportunity to design, develop, and maintain critical software systems that enable secure digital payment infrastructure serving customers worldwide.

About the Role

As a Senior Software Engineer at Mastercard, you'll take ownership of complex backend and infrastructure projects that process transactions across global networks. You'll contribute to the architecture and implementation of scalable systems, mentor junior engineers, and collaborate across teams to solve high-impact technical challenges in payments technology.

What You'll Do

• Design and develop robust software solutions for payment processing systems and core financial infrastructure
• Write clean, well-tested code following industry best practices and Mastercard's engineering standards
• Collaborate with cross-functional teams including product, security, and operations to deliver features and improvements
• Participate in code reviews, architecture discussions, and technical design sessions
• Troubleshoot production issues, optimize performance, and enhance system reliability
• Mentor junior team members and contribute to team knowledge sharing and professional development

What We're Looking For

• 5+ years of professional software development experience with strong fundamentals in object-oriented programming
• Proficiency with at least one modern programming language (Java, Python, C++, Go, or similar)
• Solid understanding of distributed systems, databases, and API design
• Experience with cloud platforms, containerization, or microservices architecture
• Strong problem-solving skills and ability to work effectively in a collaborative team environment
• Excellent communication skills and ability to document technical decisions clearly
• Bachelor's degree in Computer Science, Engineering, or related field (or equivalent professional experience)

About Mastercard

Mastercard is a global financial services technology company that connects people, businesses, and economies across more than 200 countries and territories. We're committed to building secure, innovative payment solutions that empower economic growth and financial inclusion worldwide.

How to Apply

Ready to advance your engineering career at Mastercard? Apply through this listing to be considered for this Senior Software Engineer role in Weldon Spring.