An extension of the testing fixtures set, provides utilities for interactive experimentation with the Impeller rendering subsystem. One the test author is satisfied with the behavior of component as verified in the playground, pixel test assertions can be added to before committing the new test case. Meant to provide a gentle-er on-ramp to testing Impeller components. The WSI in the playground allows for points at which third-party profiling and instrumentation tools can be used to examine isolated test cases.