Integrated circuit package with electro-optical interconnect circuitry

A multichip package may include at least a package substrate, a main die mounted on the package substrate, a transceiver die mounted on the package substrate, and an optical engine die mounted on the package substrate. The main die may communicate with the transceiver die via a first high-bandwidth interconnect bridge embedded in the package substrate. The transceiver die may communicate with the optical engine die via a second high-bandwidth interconnect bridge embedded in the package substrate. The transceiver die has physical-layer circuits that directly drive the optical engine. An optical cable can be connected directly to the optical engine of the multichip package.