Software Engineer II — O'Fallon, Missouri

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 II About the Role The Authentication Program develops and operates Mastercard's authentication solutions that help make digital payments secure, seamless, and trusted around the world. This role will focus on Identity Check, Mastercard's global authentication platform built on the EMV 3-D Secure protocol. Identity Check helps issuers, merchants, and consumers authenticate digital transactions with greater security, improved user experiences, and higher transaction approval rates. As part of our team, you will build and support highly scalable, high-performance software that protects billions of digital payment interactions globally. We are hiring a Software Engineer II to join Mastercard's Core Payments department, responsible for delivering solutions that facilitate billions of secure transactions between issuers, acquirers, and service providers worldwide. As part of the Directory Services Team, you will build and support highly scalable, high-performance software that protects billions of digital payment interactions globally. Role Software Development & Design • Design, develop, test, and maintain high-quality Java-based software components that meet engineering and business requirements. • Apply software design principles to create maintainable, scalable, and efficient solutions for moderately complex business and technical challenges. • Complete detailed technical design activities for assigned features, ensuring alignment with established architectural standards and development practices. • Participate actively in gathering requirements, technical discussions, and solution design sessions. Software Architecture & Operability • Contribute to system architecture discussions and support implementation of architectural patterns that promote scalability, performance, maintainability, and operational reliability. • Develop solutions with operational readiness in mind, including observability, monitoring, troubleshooting, and supportability considerations. • Collaborate with team members to improve system resiliency and production stability. Testing & Quality Engineering • Design, develop, and maintain comprehensive unit, functional, and integration tests to validate application behavior and ensure software quality. • Partner with quality engineers and testers to validate functionality and verify requirements are met. • Support continuous integration and deployment practices through automated testing and quality validation. Performance & Reliability • Analyze application behavior and identify opportunities to improve system performance, scalability, and reliability. • Investigate performance bottlenecks and contribute to tuning and optimization efforts within supported applications. Secure Coding & Code Quality • Apply secure coding practices to develop software that minimizes vulnerabilities and adheres to organizational security standards. • Participate in peer code reviews, providing constructive feedback to improve code quality, maintainability, security, and adherence to engineering standards. • Incorporate feedback from reviews and testing activities to continuously improve delivered solutions. Troubleshooting & Collaboration • Utilize analytical and problem-solving skills to identify, diagnose, and resolve application and system issues. • Support debugging and root-cause analysis activities across development, testing, and production environments. • Collaborate effectively with software engineers, testers, product owners, and other stakeholders in a fast-paced, Agile team environment. • Deliver assigned work within iteration timelines while maintaining a strong commitment to quality and customer outcomes. All About You • Proficient experience developing Java microservice and RESTful APIs using Java EE and Spring technologies, including Spring Boot • Knowledge of software design principles, data structures, and object-oriented programming concepts. • Proficiency working with orchestration platforms and tools, like Kubernetes and Docker. • Experience using source control and collaborative development tools such as Git and Bitbucket. • Experience working with software development lifecycle practices, including design, coding, testing, debugging, and deployment. • Experience working with relational and/or distributed data stores such as Oracle Database and Redis • Experience deploying and supporting applications running on Tomcat or similar application platforms • Hands-on experience using GitHub Copilot, Claude Code, or other AI-assisted software development tools to improve engineering productivity and code quality • Demonstrates the ability to effectively partner with AI tools while maintaining accountability for design decisions, code quality, security, testing, and production outcomes • Understanding of secure coding principles and industry standards such as OWASP, CWE, and SEI CERT • Experience using Git-based source control workflows, including branching strategies, pull requests, and peer code reviews • Experience creating and maintaining automated tests at the unit, service, and integration levels • Experience with testing frameworks such as JUnit, Mockito, and Spring Test • Understanding of software design principles, distributed systems concepts, and modern application architectures • Ability to independently troubleshoot problems, analyze root causes, and implement effective solutions • Strong analytical, problem-solving, and communication skills • Collaborative team player who actively learns from others and shares knowledge with peers • Demonstrates curiosity, ownership, and a continuous improvement mindset 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.

THIS POSTING RELECTS ONE OR MORE CURRENT VACANCIES ON OUR TEAM, AND MASTERCARD INTENDS TO FILL THIS POSITION BY 01/17/2027. If the fill date has passed, Mastercard intends to fill this position as soon as possible.

 Pay Ranges O'Fallon, Missouri: $92,000 - $147,000 USD