Abstract: A multiple piecepart alignment and attachment configuration for mating a fiber array (or even a single fiber) with a silicon photonic subassembly utilizes ever-tightening alignment tolerances to align the fiber array with a similar array of waveguides (or other devices) formed within the photonic subassembly. A box-shaped fiber holder is formed to include a plurality of grooves within its bottom interior surface to initially support the fiber array. A separate piecepart in the form of a lid is mated to, and aligned with, the silicon photonic subassembly. The lid is formed to include registration features on its underside that fit into alignment detents formed in the top surface of the silicon photonic subassembly upon attachment. The lid also includes a number of grooves formed on its underside that will capture the top surface of the fibers as the fiber holder is slide into place over the lid.