Porting a software testing execution environment to a cloud-based infrastructure can lead to significant test speedup and cost savings. However, distributing tests to new machines requires costly environment setup, and cloud infrastructures may have complex cost models. Ignoring these issues may lead to limited speedup or to unexpected cost increase. In this talk, I present “O!Snap”, a novel technique to automatically deploy and schedule tests on the cloud in a cost-efficient way. O!Snap uses a pipeline of opportunistic snapshotting, which reduces the effort to setup the testing environment, and test schedule planning, which schedules test executions according to their dependencies and optimizes the resources consumption to limit costs