Disclosed are methods, systems, and non-transitory computer-readable medium for testing and applying codes to electronic shopping carts. For instance, the method may include monitoring a shopping cart associated with an e-commerce website and with a user; in response to detecting a change to the shopping cart, testing codes with respect to a present content of the shopping cart to determine valid codes; selecting at least one of the valid codes; determining a status of the session; and performing an action based on the status and the at least one selected code. The testing the codes with respect to the present content of the shopping cart may include: cloning the shopping cart to form a cloned shopping cart in a shadow session; and/or obtaining the codes; and testing the codes on the cloned shopping cart in the shadow session to determine the valid codes.