This is a hard topic to comment on or offer help with. I'll also admit, I didn't read the link posted a few comments above to the GitHub account regarding the missing library.
It would help though if everyone could post their hardware that they are using in nix, and if possible, which drivers and modules they are using. It would be easier to determine what kind of issue there is.
It's been stated, but nix drivers are sketchy at best. NVidia typically does a good job, but even with Ubuntu, they have to be installed and configured desperately. ATI has always had really awful support. I can't count how many issues I've run into with ATi drivers. From what I understand (and I may be wrong on this), Intel 4000 and 5000 graphics are barely supported.
Also, if the graphics modules aren't installed properly, or support openGL, there will be a drop in frame rate.