How we designed and implemented a large-scale, highly parallel, rapid-turnaround testing platform. Using both open-source and custom tools, the platform scales from supporting low level unit tests to browser-based web application tests. Our platform supports both fully automated and on-demand test execution, including test-data collection, analysis and reporting. We will discuss some of the options for solving these problems and the trade-offs and the pitfalls. We will describe in detail our current operational systems using Selenium, TestNG and Jenkins on both VMware and Amazon EC2 virtualization infrastructures. Please see "0-60: QA Automation at Box" for complementary coverage of the test framework referenced in this talk.