Traditional approaches, which follow a test-driven development technique, allow a set of test cases to be exhaustively evaluated ensuring that each modification of an ontology does not violate predefined requirements. However, the time required for the evaluation of test cases is high and usually represents a bottleneck in an ontology development process. The EffTE framework tackles this problem; it relies on a graph-based model of the dependencies between test cases to support users during an ontology development process. Traversing the dependency graph is realized using breadth-first search along with a mechanism that tracks tabu test cases, i.e., test cases that will be ignored for further evaluation due to faulty parent test cases. As a result, the number of test cases that are evaluated is minimized, thus reducing the time required for validating an ontology after each modification. We demonstrate the benefits of prioritization and selection of the test cases to be evaluated with DemoEffTE . Attendees will observe the behavior of both a naive approach and the EffTE framework on different configuration settings such as different: (1) ontology size; (2) topology of the dependency graph of the test cases; and (3) number of test cases. The demo is available at: http://vocol.iais.fraunhofer.de/DemoEffTE.