Systems, computer-implemented methods, and media for updating content of a page composed of markup language in response to a triggering event method include: receiving a request that indicates a triggering event; determining the type of triggering event based on the request; determining at least one page element from amongst plural page elements of the page to be updated based on the request; generating a response to the request, the response including metadata indicating the at least one page element and the content of the at least one page element, the content of the at least one page element being composed of the markup language; and transmitting the response.