Shiny IO deploymnet error: packages not being recognized

I am attempting to deploy and app to Shiny IO. The deployment seems to be successful, but when the application is run, it terminates with the following error:

Error in value[3L] : there is no package called ‘dplyr’
Calls: local ... tryCatch -> tryCatchList -> tryCatchOne ->
Execution halted

The package identified by the error always reflects the first library(packageX) call. In the case above it was dpyr, but changes to reflect whatever is the first package I use the library function on. Any help resolving this issue would be greatly appreciated.