Senior QA Engineer - Desktop and Distributed Systems Location: LATAM, Bogota, D.C., Capital District, Colombia Our client is a US-based security company seeking a Senior QA Engineer who excels in complex, highly technical environments. You will be responsible for end-to-end manual and automated testing, ensuring that distributed services and endpoint applications (built in .NET, C++, and React) are secure, reliable, and compatible. This role requires reverse-engineering bugs, writing integration test harnesses, validating client/server behavior, and thinking like an attacker or power user. What You Will Do: Define, own, and execute comprehensive test strategies across backend services, web frontends, and desktop apps on Windows and macOS. Validate distributed system behaviors, including synchronization, persistence, fault tolerance, and security. Create detailed test plans and cases based on system behavior, API contracts, and workflows. Design and implement automation at various levels (API, integration, UI). Collaborate with development teams to identify issues early through ATDD or exploratory testing. Assist in reproducing complex bugs, including writing minimal repro apps or network mocks. Drive quality in high-scale systems with multiple backend services and desktop agents. Maintain and evolve test environments as requirements change. Requirements: 5+ years of QA experience testing backend distributed systems, desktop apps, and full-stack web apps. Hands-on experience testing Windows and macOS desktop applications, with knowledge of OS-level concepts. Experience designing and executing manual and automated tests for REST APIs, message queues, and background services. Understanding of .NET, C#, Win32 APIs, Swift, Objective-C, and web frameworks like React. Familiarity with network protocols, security testing, and reverse engineering. Proficiency with tools such as Charles/Fiddler, Wireshark, Postman, and custom test harnesses. Comfort with issue tracking, CI/CD, test management, and observability tools. Benefits: Salary: $6,000 - $7,000 USD/month + Holidays, Unlimited PTO. Additional Information: Seniority Level: Mid-Senior level Employment Type: Full-time Job Function: Other Industry: IT Services and IT Consulting This job is currently active and accepting applications. #J-18808-Ljbffr