A chip-scale coherent lidar system includes a photonic chip that includes a light source, a transmit beam coupler to provide an output signal, and a receive beam coupler to receive a received signal based on a reflection of the output signal by a target. The system also includes a transmit beam steering device to transmit the output signal out of the system, and a receive beam steering device to obtain the received signal into the system. A transmit beam curved mirror reflects the output signal from the transmit beam coupler to the transmit beam steering device. A receive beam curved mirror reflects the received signal from the receive beam steering device to the receive beam coupler. The transmit beam curved mirror and the receive beam curved mirror are formed in a substrate that is heterogeneously integrated with the photonic chip.