I think NASA had a hand in developing it for use on the space station.
The materials used cure very fast and depending on the grade, can be extremely strong.
The idea was to create tools in outer space, instead of carrying the weight of them. This greatly reduces payload weight, and gives virtually infinite flexibility to simply create the desired tool as the need arises.
The physical tool or device doesn't need to be present, it can be cast from software.
The next stage of this will include electrical (electronics) capability. We'll need another Area51 event for that one.
similar has been used in the surface mount discrete component manufacture for years to where a couple hundred resistors are printed on a ceramic plate less than two inches on a side using silver or copper ink. on a larger scale the process is used to make resistors used in automobile blower fan controllers.