[loganfsmyth]

There is a distinction to be made between having a module system, and how those modules are loaded. You can still concatenate everything together while using a module loading system, you just don't need to load the modules individually in that case.

One potential problem with concatenating everything without modules is that you then need to maintain your concatenation order based on dependencies using some other system. To his second point, you can certainly do this perfectly easily on smaller apps, but it becomes impossible as systems grow.