generating an affinity graph including nodes representing items offered by a warehouse and connections between pairs of items offered by the warehouse, wherein a connection between a pair of items represents co-occurrences of items of the pair occurring in previously received orders identifying the warehouse;

generating a colocation graph for the warehouse, the colocation graph including different regions within the warehouse, wherein the colocation graph includes connections between pairs of regions within the warehouse, and wherein the connections represent distances between regions within the warehouse;

generating instructions for placing items in regions within the warehouse by applying an optimization function to a plurality of combinations of pairs, wherein each combination of the plurality of combinations of pairs comprises a first pair including information specifying a first item and a first region within the warehouse and a second pair including information specifying a second item and a second region within the warehouse, and wherein the optimization function is a function based on a connection between the first region and the second region within the colocation graph and a connection between the first item and the second item in the affinity graph; and

transmitting the instructions for placing items in regions within the warehouse to a computing system associated with the warehouse.