Senior QA Engineer - Desktop and Distributed Systems

Our Client is a US based security company looking for a Senior QA Engineer who thrives in complex, highly technical environments. 

You will own end-to-end manual and automated testing, ensuring the distributed services and endpoint applications (built in .NET, C++, and React) are secure, reliable, and compatible. This is not a button-clicking QA role — they need someone who can reverse-engineer bugs, write integration test harnesses, validate stateful client/server behavior, and think like an attacker or power user.

What You Will Do:

1. Define, own, and execute comprehensive test strategies across backend services, web frontends, and desktop apps on both Windows and macOS.
2. Validate distributed system behaviors, including state synchronization, persistence, fault tolerance, and security guarantees.
3. Create detailed, well-researched test plans and cases based on low-level system behavior, API contracts, and desktop workflows.
4. Design and implement automation where appropriate (API/integration/UI level).
5. Partner closely with development teams to catch issues early through ATDD or early exploratory testing.
6. Contribute to reproducibility efforts for complex bugs (across platforms), including writing minimal repro apps or network mocks.
7. Drive quality in high-scale systems composed of dozens of backend services and desktop agents.
8. Maintain test environments and make sure they are evolving with requirements as they change.

Requirements

1. 5+ years of QA experience, with significant time spent testing backend distributed systems, desktop apps, and full stack web apps.
2. Strong hands-on experience testing Windows and macOS desktop applications, with a working knowledge of OS-level concepts like file systems, permissions, services, and sandboxing.
3. Experience designing and running manual and automated tests for REST APIs, message queues, and background services.
4. Understanding of .NET, C#, Win32 APIs, Swift, Objective-C, and modern web frameworks (like React) from a testing/debugging perspective.
5. Familiarity with network protocols, security testing, or reverse engineering behavior at the application level.
6. Experience using tools such as Charles/Fiddler, Wireshark, Postman, browser dev tools, or custom test harnesses.
7. Comfortable with modern issue tracking, CI/CD, test management, and observability tools.

Benefits

Salary: $6,000- $7,000 USD /month + Holidays

Unlimited PTO