Optical links help connect the world. However, state-of-the-art optical-link technologies are struggling as people and businesses consume increasing amounts of information. Optical transceivers (which transmit and receive data) are particularly burdened as transmission rates intensify and data formatting techniques become more complex. The EU-funded COMb project has a plan: use a high-performing, cost-effective silicon nitride platform to integrate indium phosphide and lithium niobate — two key materials used extensively in telecommunications — and make ultra-high-speed transceivers. COMb will use many lines and the mode-lock technique so that lasers produce extremely fast pulses of light to transmit higher data rates and obtain higher symbol rates.