The package provides a program called autotest that runs your test programs whenever you change them. Using this program, you don't have to switch between your editor and the shell since your tests are run automatically when you save them. Think "Continuous Testing".
The project is young and in alpha stage. Currently you need Dist::Zilla to play with it. To start hacking, install that module:
cpanm Dist::Zilla
Then pull sources from this repository and install the plugins needed for building the package:
dzil authordeps | cpanm
Then you may build the Perl package App::autotest via
dzil build
Have fun!