Check and Validate npmrc

[frank-dspeed]

/etc/npmrc
/home/youruser/.npmrc
/root/.npmrc
./.npmrc in the current directory next to package.json file (thanks to @CyrillePontvieux)
on windows:

c/Program\ Files/nodejs/node_modules/npm/npmrc
Then in this file the prefix is configured:

prefix=/usr
The prefix is defaulted to /usr in linux, to ${APPDATA}\npm in windows

The node modules are under $prefix tree, and the path should contain $prefix/bin

There may be a problem :

When you install globally, you use "sudo su" then the /root/.npmrc may be used!
When you use locally without sudo: for your user its the /home/youruser/.npmrc.
When your path doesn't represent your prefix
When you use npm set -g prefix /usr it sets the /etc/npmrc global, but doesn't override the local

Why?

in a open-pwa environment it is importent that we control what packages get requeired where.
make sure via "npm root -g" that it matches open-pwa

"npm config ls" lists loaded config