Senior Software Engineer
Mastercard•O'fallon, MO
•$115,000 - $184,000•Onsite
About The Position
We are seeking a Senior Software Engineer to design, develop, and maintain scalable software solutions supporting MDES initiatives and platform enhancements. This role combines strong software engineering fundamentals with automation and quality engineering practices to deliver secure, reliable, and high-performing applications. Based on the Senior Software Engineer skills matrix, the role emphasizes Software Development, Software Design, Software Architecture, Secure Coding, Code Review, Performance Engineering, Operability Engineering, Troubleshooting, and Testing.
Requirements
- Strong Java software development experience.
- Knowledge of software design, software architecture, data structures, and algorithms.
- Experience developing REST APIs and distributed applications.
- Experience with secure coding practices and code review processes.
- Strong troubleshooting and root cause analysis skills.
- Experience with unit, functional, and integration testing.
- Experience building automation using tools such as Rest Assured, Karate, Selenium, or similar frameworks.
- Understanding of CI/CD, DevOps practices, and cloud-native architectures.
- Experience with SQL and data validation.
- Knowledge of performance engineering, operability engineering, monitoring, and observability concepts.
Nice To Haves
- Payments industry experience.
- MDES, DTS, TDS, Transaction Stream, Core Processing, or Tokenization experience.
- Experience developing automation frameworks and test infrastructure.
- Experience with performance, resiliency, and large-scale distributed systems.
Responsibilities
- Design, develop, test, deploy, and support scalable software applications and services.
- Translate business requirements into secure, maintainable, and efficient technical solutions.
- Contribute to software architecture, design reviews, and technical decision-making.
- Participate in code reviews to improve quality, security, and maintainability.
- Build and enhance APIs, services, and reusable software components.
- Develop and maintain automated tests covering unit, functional, integration, API, and end-to-end scenarios.
- Integrate automated testing and quality controls into CI/CD pipelines.
- Analyze and resolve complex application, integration, and production issues.
- Improve system reliability through monitoring, observability, performance optimization, and operational readiness.
- Mentor engineers and promote engineering best practices across the team.
Benefits
- insurance (including medical, prescription drug, dental, vision, disability, life insurance)
- flexible spending account and health savings account
- 16 weeks of new parent leave
- up to 20 days of bereavement leave
- 80 hours of Paid Sick and Safe Time
- 25 days of vacation time
- 5 personal days
- 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
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What This Job Offers
Job Type
Full-time
Career Level
Senior
Education Level
No Education Listed
