Develops test cases and test execution scenarios. Conducts testing activities for subsets of complex systems and subsystems. Demonstrates a basic grasp of the principles, theories, and concepts of the software development process and has extensive subject matter expertise for the system under development or has a proven ability to gain the subject matter expertise for the system under development. Develops and executes test cases, verification of system capabilities and system enhancements or changes, test script development, requirements decomposition, requirements verification, performance testing, regression testing, high availability testing, end user testing, system and software level integration troubleshooting, test plans, test reports, root-cause analyzes, security certification testing. Performs backend data validation and interface operability verification. Develops automated test scripts and performs testing activities using automated testing tools.