Oooh, looks cool! Is there a Linux build?
That would be sweet! Linux port would rock :)
It is currently being ported: https://github.com/HackerPoet/MarbleMarcher/pull/1
So I may have something for Linux and Mac soon.
Just to let you know it works quite well on wine 3.7 (stock ubuntu package, latest) as well as wine-staging 4.0-rc3.
Tried on GTX 980TI and windowed 1600x900 gets 60fps yet there are no ultra wide resolutions available to test more (fps counter not visible). Mine is 2560x1080.