In my company we have developed a shiny application that I would call medium-sized (12k LOC in about 15 files), although I honestly have no idea what the usual size of a Shiny app is 
I was surprised to find out that each instance of the application takes about 600 MB of resident memory (Amazon Linux), even when just loaded and with no user interaction, and even more surprised that of this only 10% is shared memory.
We do need a lot of libraries, but this seems excessive.
Can you recommend a good way to hunt down what parts of the application are so memory-hungry?