Abstract: A device comprises a substrate and an IC die, which may be a photonic IC. The substrate comprises a first surface, a second surface opposite the first surface, an optical waveguide integral with the substrate, and a hole extending from the first surface to the second surface. The hole comprises a first sidewall. The optical waveguide is between the first surface and the second surface, parallel to the first surface, and comprises a first end which extends to the first sidewall. The IC die is within the hole and comprises a second sidewall and an optical port at the second sidewall. The second sidewall is proximate to the first sidewall and the first end of the optical waveguide is proximate to and aligned with the optical port. The substrate may include a recess to receive another device comprising a socket.