13. A non-transitory computer-readable storage medium having one or more instructions thereon for adding directives for versions of JavaScript files directly into source code, the instructions when executed by one or more processors causing the one or more processors to carry out: creating, at one of the processors, a version of a source file that comprises: source code from the source file and at least a portion of a client-side scripting language file for generating at least a portion of markup language for a web page to be served to a client device using a webserver; associating, at one of the processors, metadata with a preprocessed directive and a version of the source file, wherein the metadata comprises: at least a portion of the client-side scripting language file; retrieving, via one of the processors that is implemented at the webserver from a database, only the metadata associated with the preprocessed directive in the version of the source file such that the entire source file does not need to be retrieved; and in response to receiving a request for the metadata associated with the version of the source file, generating, at one of the processors in accordance with the metadata associated with the preprocessed directive and the version of the source file, at least the portion of the markup language for the web page to be served to the client device.
13. A non-transitory computer-readable storage medium having one or more instructions thereon for adding directives for versions of JavaScript files directly into source code, the instructions when executed by one or more processors causing the one or more processors to carry out: creating, at one of the processors, a version of a source file that comprises: source code from the source file and at least a portion of a client-side scripting language file for generating at least a portion of markup language for a web page to be served to a client device using a webserver; associating, at one of the processors, metadata with a preprocessed directive and a version of the source file, wherein the metadata comprises: at least a portion of the client-side scripting language file; retrieving, via one of the processors that is implemented at the webserver from a database, only the metadata associated with the preprocessed directive in the version of the source file such that the entire source file does not need to be retrieved; and in response to receiving a request for the metadata associated with the version of the source file, generating, at one of the processors in accordance with the metadata associated with the preprocessed directive and the version of the source file, at least the portion of the markup language for the web page to be served to the client device. 17. The non-transitory computer-readable storage medium of claim 13 , wherein the data on at least a portion of the client-side scripting language file comprises a file path for a directory.