Yes. Internally the image is stored 16 bits/channel - the entire recorded range is put in there, so there is guaranteed no gamut clamping here. Then there are a number of lookup table operations and calculations in floating point (32 bit/channel) precision, the result is then converted down to 8 bits/channel at the end.
...at the end you mean when exporting (save as), don't you.
There in no simple levels tool. Interesting whether you plan to implement that. However - is there any method to reposition white/black pixels on the RBG histogram with currently implemented tools.
PS
Don't take me as opponent. I use the current version and really appriaciate that it is light and clear, and reliable (eventhough it's beta). It can be observed in development of many other packages (not only photoeditors) that the more options/funtionality the less usability and still they can not catch-up with the high-end leaders (PS).