we developed an optogenetic “Cre-stiching” strategy for barcode fusion genetics. This new technology is based on light-inducible Cre-recombinase complementation. The resulting optogenetic control Cre-recombinase produces a concatenated DNA, linking together genetic barcodes. These concatenated products are handled en masse as a single sample and processed to identify interaction partners in a new type of yeast two-hybrid pipeline. This technology can also be used to generate a new kind of light-control molecular memory circuit for synthetic biology applications.