Design, build, and maintain automated tests for mobile apps, back-end APIs, and services. Use Azure DevOps, Git, Appium, RestAssured, WireMock, k6/JMeter/Gatling, Docker, Java, SQL, Bash/PowerShell. Drive coverage across unit, integration, and end-to-end layers. Ensure suites are fast and reliable in CI/CD. Contribute to code reviews, automation libraries, and test tooling. Create and run performance and non-functional tests. Collaborate with engineers and product to clarify requirements.