  Descartes is a tool that implements extreme mutation operators and aims at
finding pseudo-tested methods in Java projects. It leverages the efficient
transformation and runtime features of PIT. The demonstration compares
Descartes with Gregor, the default mutation engine provided by PIT, in a set of
real open source projects. It considers the execution time, number of mutants
created and the relationship between the mutation scores produced by both
engines. It provides some insights on the main features exposed by Descartes.
