1. A method comprising: receiving, by a computing system, a first request from a client for a target structured document; accessing, by the computing system, a data structure comprising an entry for the target structured document and one or more first resources associated with the target structured document, the one or more first resources being resources that have been previously determined to each have at least a predetermined probability to be included in a response to a future request for the target structured document that exceeds a predetermined threshold value; accessing, by the computing system, a data structure comprising an entry for the target structured document and one or more first resources associated with the target structured document, the one or more first resources are resources having been previously determined to each have at least a predetermined probability to be included in a response to a future request for the target structured document that exceeds a predetermined threshold value; in a first response phase, transmitting, by the computing system, a first portion of the target structured document to the client, the first portion of the target structured document including one or more of the first resources or references for one or more of the first resources; generating, by the computing system and after the first response phase, the target structured document and one or more parameters for one or more state objects associated with the client; in a second response phase, transmitting, by the computing system, a second portion of the target structured document, wherein the second portion of the target structured document includes a code segment; receiving, by the computing system, a second request from the client, wherein the second request is sent from the client as a result of the client executing the code segment; and transmitting, by the computing system, a response to the second request that comprises the one or more parameters for the one or more state objects.