Abstract: An apparatus and method are disclosed for preparing electrically conductive traces on a circuit board using an additive technology. The traces are directly written in a serial process with each trace being able to be individually insulated. The apparatus includes an extrusion element for extruding a first material and a stage. The stage is for holding the extrusion element and the circuit board in relative proximity and for producing relative motion between the extrusion element and the circuit board in order to extrude the first material onto the surface of the circuit board along preselected paths to produce the electrically conductive traces. According to the method of invention, a first polymerizable material is extruded onto a circuit substrate support along preselected paths to form traces, and the first polymerizable material is polymerized, the first polymerizable material being conductive after polymerization.