Global Install NPM Packages on GNU Guix

This post is not exactly a tutorial, but rather a record for myself. I've already needed to configure npm on Guix a few times and, inevitably, I ended up forgetting the steps when I installed the system again. To avoid wasting time in the future, I leave here the procedure that always solves the problem for me.

When trying to install packages globally with npm, the error is usually this:

home@user ~/workspace/dump$ npm i --global @volar/typescript
npm error code ENOENT
npm error syscall mkdir
npm error path /gnu/store/7wn5cq17bjndjxqpzlp6icyyyfxz36bf-node-22.14.0/lib/node_modules/@volar
npm error errno -2
npm error enoent ENOENT: no such file or directory, mkdir '/gnu/store/...'
npm error enoent This is related to npm not being able to find a file.
npm error A complete log of this run can be found in: /home/user/.npm/_logs/2025-12-05T18_11_26_115Z-debug-0.log

The problem happens because Guix, like NixOS, keeps the /gnu/store directory immutable. npm tries to write there and fails. The practical solution is to redirect global packages to a directory in $HOME.

# Create a directory for global packages:
mkdir ~/.npm-global

# Configure npm prefix:
npm config set prefix '~/.npm-global'

# Add the new path to PATH:
export PATH="$HOME/.npm-global/bin:$PATH"

# Confirm that the configuration has been applied:
npm config get prefix
/home/user/.npm-global

# Install the desired package:
npm install -g @volar/typescript
added 5 packages in 1s