1. A computer-implemented method for outputting data indicating a script file dependency, the computer-implemented method comprising performing computer-implemented operations for: receiving, at a computer, executable code corresponding to a resource including a reference to a client-side script file; registering, at the computer, the client-side script file associated with the reference; resolving, at the computer, a script file dependency associated with the client-side script file by selecting the client-side script file for analysis, determining that the client-side script file has not been previously analyzed, and marking the client-side script file as visited in response to determining that the client-side script file has not been previously analyzed; and outputting, at the computer, the data indicating the resolved script file dependency for the client-side script file associated with the reference, wherein the data comprises a data structure including the reference to the client-side script file and a load level at which the client-side script file is to be loaded during rendering of the resource at a client device that is in communication with the computer.