"Four human beings -- changed by space-born cosmic rays into something more than merely human." — The Fantastic Four
Cosmic Ray is a mutation testing tool for Python 3.
It makes small changes to your source code, running your test suite for each one. Here's how the mutations look:
Read the full documentation at readthedocs.
The easiest way to contribute is to use Cosmic Ray and submit reports for defects or any other issues you come across. Please see CONTRIBUTING.rst for more details.