• Own quality for core cybersecurity features and systems • Work side-by-side with security and platform engineers throughout the development lifecycle • Design test strategies for security-critical and adversarial scenarios • Build and maintain automated test frameworks and tooling (primarily Python) • Perform white-box testing and participate in design and code reviews • Test system-level properties: performance, reliability, scalability, failure modes • Debug complex issues, perform root cause analysis, and improve test coverage • Contribute to CI/CD pipelines and quality gates for security-sensitive releases