The present invention extends to methods, systems, and computer program products for automated generation of different script versions. Received scripts can include comments containing descriptive data from which instructions for implementing specified further functionality (e.g., debugging, testing, tracing, etc.) can be inferred. Received scripts can also include anonymous function names. Modules within a script pre-processor can access the descriptive data and infer instructions for implementing specified further functionality. Modules with the script preprocessor can also infer and assign global identifiers to anonymous functions such that the scripts are subsequently identifiable using the global identifiers. The modules within the script pre-processor can interoperate to generate versions of the script that implement the specified further (e.g., debugging) functionality without requiring a developer to write additional code.