Jenkins is not installing some node dependencies

I'm running a nodejs application's build on jenkins. I run node as shell script step, because I have some limitations in terms of the plugins I can install in this jenkins instance.

This is what the npm install step looks like:

#!/bin/bash +x
source ~/.bashrc
cd $WORKSPACE/ && \
nvm use 7.8.0 && node --version && npm install

The problem I have is, when npm install finishes, it doesn't install everything. If I ssh into the box where jenkins is installed and run npm install inside that project's workspace, with the same user jenkins uses, it works ok. Any ideas?

via jarz