Clean Unused Node Modules

First find all node_modules in a given workspace directory to assess how much space is wasted

cd workspace
find . -name "node_modules" -type d -prune -print | xargs du -chs

Then find and remove all node_modules in a given workspace directory

find . -name 'node_modules' -type d -prune -print -exec rm -rf '{}' \;

Source -> How to delete ALL node_modules folders on your machine and free up HD space!