SourceMaps as specified are an interop format for devtools on the client side. On the server side, you can store a lot more information since it doesn't need t

SourceMaps as specified are an interop format for devtools on the client side. On the server side, you can store a lot more information since it doesn't need to be transmitted to the client. Closure Compiler stores maps for all variables, all properties, all functions, all renamed strings, all idGenerators, etc. You can store these if you want. Google's servers store these maps and when user feedback or exceptions are logged, they are used to deobfuscate them. SourceMaps + functionMaps + propertyMaps + the others I mentioned as used to deobfuscate. This doesn't solve the problem of deobfuscating locals or heap objects. That needs an extension.