I like to write my projects in JavaScript. Since I don’t have time to juggle between all of them, it’s inevitable that they’re abandoned after a while and left as they were last touched for eternity. I bet this story feels familiar.

The node_modules Multiverse

Currently I don’t have a way to let my machine know, that I won’t work on some of my projects for a while. It does not know, that it’s safe to get rid of the large unnecessary build artifacts and dependencies. I mostly use node that comes with npm package manager by default. Npm has a huge downside illustrated below.

Heaviest objects in the universe

Heaviest objects in the universe (source: reddit)

For every project that you’re woking on, it’ll create a new separate node_modules folder, downloading all dependencies and pack it into a single tree structure. This node_modules folder can quickly grow to hundreds of megabytes even if you only use a small set of dependencies. That’s because your dependencies most likely depend on other projects, and so on…

Out of Space

In the last couple of days I’ve been struggling with the amount of free space I have. I’ve cleaned up in the most obvious places aleady, but it was not enough.

I decided to take a deepdive into my projects folder stucture.

find ~/project -iname 'node_modules' -type d | grep -v '/node_modules/'

I looked for leaf folders with the name node_modules. To my surprise I found around 50 sandboxes, playgrounds, current projects, recently abandoned projects and REALLY old ones.

At that point rage was my guiding star, so I went through them one by one, and removed the unused ones.

Now I know that there are better ways to tackle this problem. One of which is npkill that promises to easily find and remove old and heavy node_modules folders.

In the end I managed to save up around 20GB of space… I let it sink in. 20GB.

How to solve it

At first I thought about moving to docker for all frontend related development. I could use development images, build the code there and move the problem away with one level of abstraction.

I already have a preferred way to clean up dangling images, but I felt like there must be a better way to solve the space problem globally.

Reuse Modules with pnpm

A few weeks ago I’ve heard about pnpm, but I did not feel the urge then to look into it. Now I felt it’s the perfect time to try something new.

The feature I like in it the most is that it uses a single loaction to download all modules throughout all the projects that you use with pnpm. During each install it even shows how many packages were reused from the store. It’s really pleasing.

I also like that it can coexist with npm, if you have some special needs that it can not yet solve with pnpm.

The project has similar motivation than my needs, even it’s name stands for performant npm.

Getting started with pnpm

The official docs are a good source to have it up and running in a glance.


The installation was pretty straightforward for me. I chose a feasible one from their listed ways and it worked flawlessly.

corepack enable
corepack prepare pnpm@7.2.1 --activate

How to add/remove modules

The pnpm add PACKAGE command adds the PACKAGE dependency, and as an added bonus it makes sure that the new module is added to your package.json as well. So hopefully you won’t ever run into a problem, that your code depends on a package that you’ve installed, but your coworker can not run the app.

# use is-number package as an example
pnpm add is-number

The pnpm remove PACKAGE removes it from package.json and the node_modules folder. I’d like to add that it won’t remove the package from the global store, so reinstalling a package is lightning fast.

# use is-number package as an example
pnpm remove is-number

How to clean up after a project

The pnpm store prune command removes unreferenced projects from the global store. The global store is not cleaning up itself, and contains multiple versions of the same pakages, as per the dependencies need it. Although when you update some packages in a project, some modules might only have been referenced by your old versions, thus they can be safely deleted.

It is advised to run this command once in a while, not too often though.

Abandon a project on purpose

When you no longer develop a project, you can just remove the node_modules folder as usual. The new thing to do is to run pnpm store prune and enjoy your regained free space.

# abandon a project
cd $(pnpm root)/..
rm -rf ./node_modules

pnpm store prune

Where is the global store

You can find the store’s location with pnpm store path command.

pnpm store path

My current challenge is different node versions

I use n for managing node versions. I did not find any documentation of how these can coexist. Although I must add that it’s not the best searchable name.

I have some old projects that only work with older node versions, and I might need to switch between them occasionally in the future.

pnpm env can hopefully help me with that.

pnpm env use --global lts
pnpm env use --global 14.17.0

Note: --global flag is mandatory for this command as per v7.x

It’s said that it works with nvm, I might try that in a next iteration.

Closing Words

I’m glad that I found pnpm, I know my hard drive will thank me later. I already like how much module it reuses in the few projects I utilized it in. It already helped me catch bad imports, it’s a good start.

I just need to learn to write pnpm instead of npm from now on.

I’m not affiliated in any way with this project or its authors. This post represents my opinion and limited experience with this tool.

Happy coding!