A technology that reconstitutes the matter of a rock, reforging its atomic links to reduce its volume by 200, which results in nara. Practically, it was used to recycle excess excavated or discarded rock.
At the time of the Fall of D'ni the compounder was a small and squat machine with a deep, wedge-shaped metal tray on top and a mesh cage on its underside.
A button on its face made a metal lid slide across over the tray to receive rock fragments. After a low, grinding sound, the nara is molded into a storable form, a bulky red cylindrical jacket. The lid slides back and the cylinder falls in the cage.