Variable font stuff.
This is Apple SF Display, which ships with macOS as a variable font.
@rutherford is this only shipping on Mojave?
@anreoh As far as I know it's been around since High Sierra as a variable font. Although it won't appear in your font manager, some applications (like python, which I made the animation with) will show it as '.SFNSDisplay'
@rutherford I have been using SF mono for the last couple of days, what a beautiful family
@rutherford still mesmerized by this design
Revel in the marvels of the universe.