Software Engineer II

Mastercard is seeking a Software Engineer II in O’Fallon, Missouri to help build and support software that supports critical business capabilities. In this onsite role, you will partner with engineers, product partners, and stakeholders to deliver scalable, secure, high-quality solutions while expanding your technical expertise end-to-end.

What you’ll do

• Participate in team prioritization discussions with Product and Business stakeholders to align on requirements and delivery objectives.
• Estimate and deliver assigned work across design, development, testing, deployment, configuration, and documentation.
• Contribute to code, design, and process discussions, evaluating trade-offs to identify practical solutions.
• Join sprint planning, backlog refinement, demos, and acceptance discussions with Product Owners and stakeholders.
• Build understanding of end-to-end technical architecture, business domain, and system dependencies for supported applications.
• Design, develop, test, and maintain software applications and services with security, scalability, resiliency, and performance in mind.
• Participate in code reviews and provide feedback that supports code quality, maintainability, and engineering standards.
• Support implementation of engineering best practices, technology standards, and established development frameworks.
• Troubleshoot application, system, and production issues by working with team members to identify root causes and implement fixes.
• Contribute to CI/CD pipelines, deployment automation, and operational readiness activities.
• Support and guide new team members through knowledge sharing and collaboration.
• Look for opportunities to improve processes, reduce inefficiencies, and increase team productivity.
• Share knowledge, reusable components, patterns, and best practices across teams, guilds, and engineering communities.

What you’ll need

• Experience developing software applications using modern programming languages and development frameworks.
• Understanding of software design principles, software architecture, data structures, and algorithms with the ability to build maintainable, scalable solutions.
• Experience applying secure coding practices and familiarity with industry standards such as OWASP, CWE, and SEI CERT.
• Knowledge of vulnerability management and experience using code quality and security scanning tools such as Sonar, Checkmarx, Veracode, Zally, or similar.
• Understanding of core engineering principles for mission-critical systems, including security, reliability, scalability, performance, operability, testing, and customer experience.
• Experience designing and maintaining unit, functional, integration, and automated tests.
• Familiarity with test automation, behavior-driven development (BDD), and test pyramid methodologies.
• Experience participating in code reviews and troubleshooting application and production issues in distributed systems.
• Ability to collaborate with engineering teams and business stakeholders to estimate requirements and prioritize work by business value.
• Understanding of domain-driven design concepts and applying business requirements to software solutions.
• Experience with CI/CD pipelines and release automation tools such as Jenkins, Azure DevOps, AWS pipelines, XL Release, or similar.
• Familiarity with build, artifact, and dependency management tools such as Artifactory, JFrog, or equivalent platforms.
• Experience supporting application monitoring, observability, performance analysis, and operational health using industry-standard tools.
• Experience building and supporting highly available production systems.
• Preference for experience with cryptography, encryption technologies, or security-focused applications.
• Preference for payment industry experience (not required).
• Bachelor’s degree in Computer Science, Software Engineering, Information Technology, or a related field, or equivalent practical experience.

Tools and technologies

• OWASP, CWE, SEI CERT
• Sonar, Checkmarx, Veracode, Zally
• Jenkins, Azure DevOps, AWS pipelines, XL Release
• Artifactory, JFrog
• CI/CD, BDD
• Unit testing, functional testing, integration testing

Benefits

• Insurance including medical, prescription drug, dental, vision, disability, and 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.

Corporate security responsibility

• 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.
• Complete all periodic mandatory security trainings in accordance with Mastercard’s guidelines.

Pay range: O’Fallon, Missouri: $92,000 - $147,000 USD per year.