Current status: experimental.
Do not use in production (or anywhere else)!
But, if you feel adventurous:
We use the kreXX lib for debugging, but unbundeldet it.
This M2 extension provides the backend module and some M2 specific overwrites for the kreXX lib.
Use
composer require brainworxx/krexx:2.4.0
to install the kreXX lib before you can use this backend module.