Lead Software Development Engineer in Test (Lead SDET)

About the role

Mastercard’s Global Credit Card Authorization team is looking for a Lead Software Development Engineer in Test (Lead SDET) to own quality engineering for a high‑throughput transaction processing platform. This hybrid role in O’Fallon, MO, combines deep technical expertise with leadership to shape testing strategies, mentor engineers, and ensure production‑ready releases.

Key responsibilities

• Lead development of system components in C and create unit tests in C++ using Google Test.
• Translate design documents into detailed test plans, functional, integration, and UAT strategies.
• Own end‑to‑end quality outcomes for authorization services, ensuring performance, resilience, and reliability.
• Review logs and traces to guarantee comprehensive test coverage and system validation.
• Drive root‑cause analysis, remove testing blockers, and ensure timely, high‑quality releases.
• Promote continuous improvement in test automation, quality engineering practices, and CI/CD integration.
• Collaborate with engineering, product, and operations teams across a global environment.
• Guide and mentor SDETs and QA engineers, fostering a culture of accountability and continuous improvement.

Required profile

• Extensive experience as an SDET or Quality Engineer on large‑scale, high‑throughput systems.
• Proven leadership and mentorship abilities.
• Strong analytical skills with a focus on production readiness and risk mitigation.

Required skills

• C programming
• C++ programming
• Google Test framework
• Test automation
• CI/CD pipelines