It feels somewhat dismissive to call Infinifactory “SpaceChem – but in 3D!”, but that’s exactly what it is – indeed, that’s exactly what it’s marketed as in the Steam blurb:
LIKE SPACECHEM… IN 3D! Design and run factories in a first-person, fully 3D environment.
In fairness to Zachtronics they did make SpaceChem, and so in describing their third mass-market game this way they’ve just saved me a whole lot of bother trying to sum up what Infinifactory is about. It’s SpaceChem. But in 3D.