Nickel/photoredox catalyzed C–N couplings of hydrazine-derived nucleophiles provide a powerful alternative to Pd-catalyzed methods. This continuous-flow photochemical protocol, optimized using design of experiments, achieves these couplings in short residence times, with high selectivity. A range of (hetero)aryl bromides and chlorides are compatible and understanding of process stability/reactor fouling has been discerned.