Application Start-Up - shiny.io

I am trying to minimize the number of packages loaded during the start-up of my application on shiny.io. My application takes a couple minutes to load and I'd like to reduce this time.

I have a ui.R, server.R and global.R file (which sources my functions and separate library file (100 packages)).

Rather than load 100 packages at application start-up, is it ok to move these packages to the function files so they are loaded only when the function is called and not at application start-up?

Any useful guidance is appreciated!