Good!
Well done.
Since your project continues to grow and you're basically accepting an input file and giving an output file to the user, have you ever thought of accepting also a stream as an input and outputting a stream as an output?
You probably figured out yourself what I mean by that, but I'm gonna say it anyway: introducing Avisynth+ support.
There are still alternatives, but, you know, the more tools we have, the better.