This disclosure is directed to methods and systems for delivering an item of web content requested by a client. An intermediary between a client and a server may intercept a request from the client to the server for an item of web content. The intermediary may split the item of web content into a plurality of fragments. The intermediary may identify, responsive to the request, a first fragment of the plurality of fragments to transmit to the client. The intermediary may inject executable code into the first fragment of the plurality of fragments. The executable code may be configured to conditionally incorporate additional fragments from the plurality of fragments into the first fragment at the client.