my apologies. I thought I replied to this. I did not get an error after trying this the next day, and everything seems to be working as expected. I suppose a restart of R was in order for some reason.
> deployApp()
Preparing to deploy application...DONE
Uploading application bundle...DONE
Deploying application: 10654...
Waiting for task: 33533
building: Parsing manifest
building: Building package: digest (0.6.3)
building: Building package: xtable (1.7-1)
building: Building package: BH (1.51.0-4)
building: Building package: RJSONIO (1.0-3)
building: Building package: Rcpp (0.11.0)
building: Building package: httpuv (1.2.0)
Error: Unhandled Exception: Child Task 33534 error: Unhandled Exception: Error building httpuv (1.2.0). Build exited with non-zero status: 1