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Mastercard · O'Fallon, Missouri

# Senior Software Engineer

O'Fallon, Missouri Senior individual contributor $115,000 - $184,000 Software Engineering 

Listed on Mastercard’s official careers site. Posted October 28, 2026. Check that it is still open and apply there.
[Apply on Mastercard’s careers site →](https://mastercard.wd1.myworkdayjobs.com/CorporateCareers/job/OFallon-Missouri/Senior--Software-Engineer_R-293457)

[OpenNash Jobs](https://jobs.opennash.com/) / [Mastercard](https://jobs.opennash.com/companies/mastercard/) / Senior Software Engineer

## Job description

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 The Decision Management Program (DMP) delivers industry‑leading intelligence that enables faster, smarter decisioning at global scale across the payment journey and beyond. Through a suite of products, DMP structures and applies complex business logic to help teams manage risk, adapt quickly to changing regulatory, geopolitical, or market conditions, and drive profitable customer engagements.

Built for resiliency, availability, and future growth, DMP empowers Mastercard’s market-facing programs with agile, intelligent decision management capabilities worldwide. A Senior Software Engineer is an experienced individual contributor who designs, develops, tests, deploys, and maintains complex backend software applications and services, with a strong focus on Java-based development. This role applies deep technical expertise to solve nontrivial engineering problems, influence design decisions, and improve engineering practices while collaborating closely with product, operations, and other stakeholders.

Senior Software Engineers operate with a high degree of autonomy, contribute across the full software development lifecycle, and raise the technical bar through backend development, code quality, automated testing, system design, secure engineering practices, and knowledge sharing.

### Role Responsibilities
- Own software delivery activities at the application or software-component level, including backend development, testing, deployment, release, configuration, and documentation.
- Design and develop scalable, secure, reliable, and maintainable Java-based applications, APIs, services, and backend components.
- Translate business and technical requirements into scalable, secure, reliable, and maintainable software designs.
- Develop high-quality Java software using appropriate algorithms, data structures, coding standards, and engineering best practices.
- Design, develop, and maintain automated unit, functional, integration, and regression tests to validate software functionality, service interactions, and code changes.
- Incorporate test automation and regression testing into the software development lifecycle to support code quality and reliable releases.
- Troubleshoot, diagnose, and refactor existing code to improve quality, maintainability, performance, and reliability.
- Apply secure coding practices throughout the software development lifecycle to identify and reduce application vulnerabilities.
- Adopt new programming languages, frameworks, and architecture patterns based on business and technical needs.
- Participate in the team’s agile processes, technical decisions, backlog refinement, and prioritization activities.
- Deliver prioritized backlog work in partnership with the full scrum team, seeking guidance when appropriate.
- Automate software build, testing, deployment, operational, and runtime processes.
- Lead code, design, and process trade-off discussions within the team when required.
- Drive the integration of backend services and APIs with a focus on the customer journey and overall experience.
- Perform product demonstrations and participate in acceptance discussions with Product Owners.
- Improve operational readiness by incorporating reliability, observability, monitoring, and measurable engineering practices into software solutions.
- Analyze and optimize applications and services for performance and scalability through testing, tuning, and ongoing evaluation.
- Develop a comprehensive understanding of end-to-end technical architecture, system interactions, and dependencies.
- Drive the adoption of technology standards and approved frameworks, and review the development, testing, design, and automation work of team members.
- Mentor and guide new and less-experienced team members through technical support, code reviews, and knowledge sharing.
- Identify opportunities to improve engineering processes, reduce waste, and increase team productivity.
- Share and seek knowledge within relevant Guilds and Programs to promote the reuse of patterns, libraries, tools, and practices. All

### About You
- Strong experience developing backend applications and services using Java, with demonstrated proficiency building production-quality software.
- Strong understanding of Java development, backend software design, APIs, service-oriented architectures, algorithms, and data structures.
- Experience applying secure coding standards and developing scalable, maintainable software.
- Experience developing and maintaining automated unit, functional, integration, and regression testing as part of software development.
- Experience incorporating test automation into CI/CD and software delivery practices to improve quality and release reliability.
- Strong code-review skills, including the ability to identify quality, security, maintainability, and standards-compliance concerns.
- Experience troubleshooting complex application and system issues.
- Familiarity with performance engineering, performance tuning, automation, observability, and operational-readiness practices.
- Solid experience with software development processes and one or more Application Lifecycle Management tools.
- Success producing high-quality software designs, technical deliverables, and documentation.
- Demonstrated experience applying AI technologies or capabilities within a software engineering context.
- Proactive, detail-oriented, and able to operate independently in a fast-paced environment.
- Passion for continuous learning and solving challenging technical problems. Strong verbal and written communication, relationship-building, collaboration, and organizational skills.
- Strong commitment to the timely delivery of key objectives.
- Sound decision-making skills and a continuous-improvement mindset.
- Bachelor’s degree in Computer Science or a related technical field, or equivalent practical 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. THIS POSTING RELECTS ONE OR MORE CURRENT VACANCIES ON OUR TEAM, AND MASTERCARD INTENDS TO FILL THIS POSITION BY 01/18/2027. If the fill date has passed, Mastercard intends to fill this position as soon as possible.

### Pay Ranges O'Fallon, Missouri

$115,000 - $184,000 USD

## At a glance
- Posted by the employer: Oct 28, 2026
- First seen by OpenNash: Oct 25, 2026
- Last checked: Nov 1, 2026
- Listed for: 7 days
- Location: O'Fallon, Missouri
- Pay: $115,000 - $184,000[Apply on Mastercard’s careers site →](https://mastercard.wd1.myworkdayjobs.com/CorporateCareers/job/OFallon-Missouri/Senior--Software-Engineer_R-293457)

## Hiring at Mastercard
- Open jobs: 1,014
- New in the last 7 days: After two weekly collections
- Tracked since: Jul 10, 2026

[All Mastercard jobs](https://jobs.opennash.com/companies/mastercard/) · [Weekly hiring report](/reports/hiring/)

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### [Lead Software Engineer](https://jobs.opennash.com/companies/mastercard/jobs/665227cd826276b2809b/)

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