til / delete unused node modules

After developing on a computer for a while you’ll probably end up with a bunch of projects. If those projects are JavaScript there’s a good change that they contain a node_modules directory. From time to time it’s a good idea to remove all of these folders, since they can get quite big, and re-download the dependencies in the projects you’re actively using.

I have aliased the following command to node-prune and have been using it a couple of years without any issues. When I last ran the command on I got back ~40 GB of disk space. Use it at your own risk.

alias node-prune='find . -name "node_modules" -type d -prune -exec rm -rf '{}' +'

There’s a lot to the command, but here’s an explanation of each part to demystify it.

find - A command that comes built-in with MacOS and Linux.
. - Look from this location
-name "node_modules" - Make sure the last component of the pathname matches node_modules
-type d - We are looking for a directory (d)
-prune - Stops find from descending into the folder, meaning that it won’t look for node_modules inside node_modules and so on.
-exec rm -rf '{}' + - Runs the specified command, rm, with flags r (remove directory) and f (do not ask for confirmation no matter what the file permissions are). '{}' will be replaced by the pathname that’s been found. + means that find will append all the file paths to a single command instead of running rm for each.

If you only want to find and display the size of the folders you can use the following command

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

There’s also npkill which looks up and displays node_modules, displays their size and allows you to delete the folders. Run it by using npx npkill.

Erik Rasmussen. (2021-11-09). Tweet