Looks very good so far,. i like the way the nodes wobble when we grab them and move them around, great touch,. also love that we can create new nodes and expand on this great interface. Lua is a nice language for this.
I found this thing in quite a random way, literally ran into on itch. I haven't done much with it but I'll keep it handy. My current project isn't pixel art styled but I may do one in the future. This thing to me basically seems like Substance Designer but for pixel art. Some more nodes would make things better. I know people have made custom nodes too, which is good, but some of the basics are missing, like shapes/polys. It would also be nice to be able to put text to parameters instead of just numbers, so we know that shape 1 is a "pyramid."
It seems like you took some features from Substance Designer as inspiration...it just seems like the more the better you know.