Software Engineer I at Mastercard in O’Fallon, MO

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

Software Engineer I

About the Role As a Software Engineer, you'll work alongside experienced engineers to design, develop, test, deploy, and support software solutions while building a strong foundation in modern software engineering practices.

This is a great opportunity for early-career engineers who are passionate about technology, eager to learn, and excited to contribute to scalable, secure, and high-quality software. You'll gain hands-on experience across the software development lifecycle while collaborating with cross-functional teams to solve real-world business challenges.

Role • Design, develop, test, deploy, and maintain software applications and services • Contribute to software design and architecture discussions to build scalable, maintainable, and secure solutions • Develop high-quality code that meets technical, performance, and reliability requirements • Create and execute unit, functional, and integration tests to ensure software quality and stability • Participate in code reviews and apply engineering best practices to improve code quality and maintainability • Research and evaluate technical solutions to address changing business and customer needs • Apply secure coding practices throughout the software development lifecycle • Support performance engineering activities to improve application responsiveness and scalability • Troubleshoot and resolve application and system issues with guidance from senior team members • Contribute to system operability, monitoring, reliability, and support readiness • Create and maintain technical, testing, and system documentation • Follow Mastercard development, quality assurance, and audit compliance standards • Support software metrics collection, reporting, and continuous improvement initiatives • Collaborate effectively within diverse, matrixed, and geographically distributed teams • Leverage AI-assisted development tools responsibly while validating outputs for quality, security, and accuracy • Continuously learn new technologies, frameworks, and engineering practices

All About You • Foundational understanding of software development principles, methodologies, and best practices • Understanding of software design concepts and how applications are structured and built • Exposure to software architecture principles, patterns, and system interactions • Knowledge of data structures and their use in solving technical problems efficiently • Familiarity with object-oriented programming and modern programming languages such as Java, Python, C#, or similar • Understanding of unit, functional, and integration testing concepts • Knowledge of code review practices and software quality standards • Familiarity with secure coding practices and application security fundamentals • Understanding of application performance, scalability, and reliability concepts • Ability to troubleshoot and analyze software and system issues using structured problem-solving approaches • Exposure to monitoring, support, or operational readiness concepts is a plus • Strong analytical, organizational, and communication skills • High-energy, detail-oriented, and self-motivated with a desire to learn and grow • Ability to work collaboratively in a diverse, team-oriented environment • Comfortable receiving guidance while developing technical expertise • Bachelor's degree in Computer Science, Information Technology, Management Information Systems, or equivalent practical experience • 0–12 months of software engineering experience through internships, academic projects, co-ops, bootcamps, or professional experience

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 reasonable_accommodation@mastercard.com 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: $72,000 - $115,000 USD