Lead Sdet Jobs (NOW HIRING)

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
Lead Software Development Engineer in Test (Lead SDET)
Overview:
Mastercard's Global Credit Card Authorization team is seeking a Lead Software Development Engineer in Test (Lead SDET) to drive quality engineering for one of the most critical transaction processing platforms in the world. This platform facilitates billions of transactions annually between issuers, acquirers, and service providers across the globe.
In this role, you will combine deep technical expertise with leadership to define and scale testing strategies for complex, high-throughput systems. You will play a pivotal role in elevating engineering standards, strengthening production readiness, and embedding quality across the entire software development lifecycle. You will also mentor engineers and influence quality practices across teams.
This is a hybrid role based in O'Fallon, MO, with an expectation of three days per week onsite.
Role:
• Lead development of complex system components in C and design corresponding unit tests in C++ using Google Test.
• Translate high-level design documents and system architecture into detailed, actionable test plans and validation strategies.
• Design, implement, and execute functional, integration, and User Acceptance Testing (UAT) strategies across the platform.
• Own end-to-end quality outcomes for key authorization services, ensuring high performance, resilience, and reliability.
• Review system traces, logs, and runtime behavior to ensure comprehensive test coverage and system validation.
• Lead root cause analysis for complex issues, driving resolution and preventing recurrence.
• Identify, prioritize, and remove testing blockers to ensure timely and high-quality release delivery.
• Ensure production readiness by proactively identifying risks, validating fixes, and resolving defects prior to deployment.
• Drive continuous improvement in test automation, quality engineering practices, and CI/CD integration.
• Collaborate across engineering, product, and operations teams in a fast-paced, global environment to align on quality standards.
• Guide and mentor SDETs and QA engineers, fostering a culture of accountability, ownership, and continuous improvement.
• Champion high-confidence releases by embedding quality early in the development lifecycle and improving platform-wide testing strategies.
All About You:
• Extensive experience as a Software Development Engineer in Test (SDET), Quality Engineer, or similar role in large-scale, high-availability systems.
• Strong proficiency in C/C++ with hands-on software development experience for test development and system validation.
• Experience designing and implementing automated test frameworks and scalable testing strategies.
• Proven ability to develop and execute functional, integration, and User Acceptance Testing (UAT) for complex systems.
• Ability to translate high-level design and architecture documents into detailed, actionable test plans.
• Strong understanding of software quality engineering practices, defect lifecycle management, and test coverage methodologies.
• Experience working in Linux/Unix environments.
• Proficiency in scripting languages, preferably shell scripting, for automation and test execution.
• Experience with CI/CD pipelines, automated testing tools, and modern DevOps practices.
• Strong experience using source control systems (Git preferred) in collaborative development environments.
• Deep understanding of distributed systems, high-throughput architectures, and performance considerations.
• Strong analytical and problem-solving skills with a focus on root cause analysis and defect prevention.
• Proven ability to lead testing efforts and influence quality strategy across teams or domains.
• Excellent communication and stakeholder management skills, with the ability to influence both technical and non-technical audiences.
• Experience mentoring or leading engineers is strongly preferred.
• Bachelor's degree in Computer Science, Engineering, Mathematics, or a related technical field (or equivalent practical experience)
This role is not eligible for Mastercard's work authorization sponsorship. As such, candidates must be eligible to work in the United States, now as well as in the future, without employer sponsorship.
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.
Pay Ranges
O'Fallon, Missouri: $140,000 - $231,000 USD