If you worked with javascript for quite some time, you probably have many projects spread around your computer. Recently my mac is super low on memory and I could not find anything to remove.
So I started "debugging" through my folders and I noticed a lot of MBs inside all my projects node_modules.
In the bottom line I removed 30 GB !
# this will output the memory size node_modules take
find . -name "node_modules" -type d -prune -print | xargs du -chs
# this will remove all node_modules
find . -name 'node_modules' -type d -prune -print -exec rm -rf '{}' \;