In various embodiments, optical fibers may be placed into V-shaped grooves in a substrate. A lid may then be placed on top of the optical fibers to hold them accurately in place, and the lid may be attached to the substrate using a reflow solder technique. Epoxy may then be applied as a strain relief. Because the V-shaped grooves and optical waveguides are manufactured with precision on the same substrate, precise alignment between these two may be achieved. Because the epoxy is applied after reflow, the epoxy may not be exposed to reflow temperatures, which might otherwise cause the epoxy to distort during the cure process.