In Instrumenting VBA for Google Analytics and Universal analytics measurement protocol for your GAS libraries I showed how you could us Google Analytics to measure usage of modules and libraries.
In db access to a variety of databases from Excel, the example accesses 6 or 7 different databases directly from Excel using DataHandler REST API which is built with Google Apps Script and uses many of the drivers covered in Database abstraction with google apps script. By instrumenting all of this with analytics, not only can I track historically who is using what module (see this blogpost), but also I can watch progress using real time analytics to make sure all the right cloud based libraries are modules are being called in the right order. In other words I can see if any integration fails to do what I expect in real time. I found this to be invaluable when trying to debug this complex environment.
This really boring video, where nothing much seems to happen, shows a VBA process kicking off, followed by each of the Google Apps Script processes to which the backend work has been delegated to - all in the comfort of a single real time Analytics screen. If you stick with it, watch carefully the names of the screens changing as the different libraries kick in.
Here's some slides frpm #devfestlon on this topic
See Database abstraction with google apps script for more on this, and Universal analytics measurement protocol for your GAS libraries for how you can implement this.