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.

Responsibilities

• Design, develop, test, deploy, and maintain software applications and services
• Contribute to software design and architecture discussions to build scalable, maintainable, and secure solutions
• 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
• 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

Requirements

• Foundational understanding of software development principles, methodologies, and best practices
• Understanding of software design concepts and how applications are structured and built
• 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
• Knowledge 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
• Strong analytical, organizational, and communication skills
• High-energy, detail-oriented, and self-motivated with a desire to learn and grow
• 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

Qualifications

• Ability to work collaboratively in a diverse, team-oriented environment

Skills

• Software development principles, methodologies, and best practices
• Software design concepts and application structure
• Data structures and problem-solving efficiency
• Object-oriented programming and modern programming languages
• Unit, functional, and integration testing
• Code review practices and software quality standards
• Secure coding practices and application security
• Application performance, scalability, and reliability
• Structured problem-solving approaches
• Collaboration and teamwork

Benefits

• 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)
• Paid sick and safe time (80 hours), vacation time (25 days), and personal days (5 days)
• U.S. observed holidays
• 401k with a best-in-class company match
• Deferred compensation for eligible roles
• Fitness reimbursement or on-site fitness facilities
• Tuition reimbursement

Pay

The pay range for this role in O'Fallon, Missouri is $72,000 - $115,000 USD. The actual offer may vary based on multiple factors, including but not limited to location, job-related knowledge, skills, and experience.

Schedule

Full-time schedule is typically 40 hours per week.

Corporate Security Responsibility

All activities involving access to Mastercard assets, information, and networks come 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
• Complete all periodic mandatory security trainings in accordance with Mastercard’s guidelines