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

Overview
We are seeking a Senior Software Engineer to design, develop, and maintain scalable software solutions supporting MDES initiatives and platform enhancements. This role combines strong software engineering fundamentals with automation and quality engineering practices to deliver secure, reliable, and high-performing applications. Based on the Senior Software Engineer skills matrix, the role emphasizes Software Development, Software Design, Software Architecture, Secure Coding, Code Review, Performance Engineering, Operability Engineering, Troubleshooting, and Testing.

Key Responsibilities
• Design, develop, test, deploy, and support scalable software applications and services.
• Translate business requirements into secure, maintainable, and efficient technical solutions.
• Contribute to software architecture, design reviews, and technical decision-making.
• Participate in code reviews to improve quality, security, and maintainability.
• Build and enhance APIs, services, and reusable software components.
• Develop and maintain automated tests covering unit, functional, integration, API, and end-to-end scenarios.
• Integrate automated testing and quality controls into CI/CD pipelines.
• Analyze and resolve complex application, integration, and production issues.
• Improve system reliability through monitoring, observability, performance optimization, and operational readiness.
• Mentor engineers and promote engineering best practices across the team.

Required Skills
• Strong Java software development experience.
• Knowledge of software design, software architecture, data structures, and algorithms.
• Experience developing REST APIs and distributed applications.
• Experience with secure coding practices and code review processes.
• Strong troubleshooting and root cause analysis skills.
• Experience with unit, functional, and integration testing.
• Experience building automation using tools such as Rest Assured, Karate, Selenium, or similar frameworks.
• Understanding of CI/CD, DevOps practices, and cloud-native architectures.
• Experience with SQL and data validation.
• Knowledge of performance engineering, operability engineering, monitoring, and observability concepts. [
Preferred Experience
• Payments industry experience.
• MDES, DTS, TDS, Transaction Stream, Core Processing, or Tokenization experience.
• Experience developing automation frameworks and test infrastructure.
• Experience with performance, resiliency, and large-scale distributed systems.

Success Measures
• Delivery of secure, scalable, and maintainable software solutions.
• Increased automation coverage and engineering efficiency.
• High-quality releases with minimal defect leakage.
• Improved system reliability, performance, and operational readiness.
• Strong technical leadership and mentoring impact.

Mastercard is a merit-based, inclusive, equal opportunity employer that considers applicants without regard to gender, gender identity, sexual orientation, race, ethnicity, disabled or veteran status, or any other characteristic protected by law. We hire the most qualified candidate for the role. In the US or Canada, if you require accommodations or assistance to complete the online application process or during the recruitment process, please contact [email protected] and identify the type of accommodation or assistance you are requesting. Do not include any medical or health information in this email. The Reasonable Accommodations team will respond to your email promptly.

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.

In line with Mastercard’s total compensation philosophy and assuming that the job will be performed in the US, the successful candidate will be offered a competitive base salary and may be eligible for an annual bonus or commissions depending on the role. The base salary offered may vary depending on multiple factors, including but not limited to location, job-related knowledge, skills, and experience. Mastercard benefits for full time (and certain part time) employees generally include: insurance (including medical, prescription drug, dental, vision, disability, life insurance); flexible spending account and health savings account; paid leaves (including 16 weeks of new parent leave and up to 20 days of bereavement leave); 80 hours of Paid Sick and Safe Time, 25 days of vacation time and 5 personal days, pro-rated based on date of hire; 10 annual paid U.S. observed holidays; 401k with a best-in-class company match; deferred compensation for eligible roles; fitness reimbursement or on-site fitness facilities; eligibility for tuition reimbursement; and many more. Mastercard benefits for interns generally include: 56 hours of Paid Sick and Safe Time; jury duty leave; and on-site fitness facilities in some locations.

Pay Ranges

O'Fallon, Missouri: $115,000 - $184,000 USD