Solving npm Usage of the –dev option is deprecated. Use –only=dev instead.


You want to install development dependencies for a NodeJS package using

npm install --dev

but you get this error message:

npm WARN install Usage of the `--dev` option is deprecated. Use `--only=dev` instead.


You can use

npm install # Install normal (not development) dependencies
npm install --only=dev # Install only development dependencies

instead. Note that npm install --only=dev will only install development dependencies, so in most cases you want to run both commands.

Using nodemon without a global installation


You want to use nodemon in order to automatically reload your NodeJS server, however you don’t want to require a global installation (npm install -g nodemon) but instead install it locally into the node_modules directory:


First, install nodemon as dependency (

npm install --save-dev nodemon

We installed it as development dependency for this example, but it will work just as well if you install it as a normal dependency using --save instead of --save-dev.

After that, add a script entry in package.json:

"scripts": {
  "devserver": "./node_modules/nodemon/bin/nodemon.js index.js"
}, /* rest of package.json */

Replace index.js with the name of the file you want to run using nodemon.

Now you can start the development server using

npm run devserver

How to fix npm “Cannot find module ‘graceful-fs'” error


When running any npm command, you get a stacktrace similar to the following:

Error: Cannot find module 'graceful-fs'
at Function.Module._resolveFilename (module.js:338:15)
at Function.Module._load (module.js:280:25)
at Module.require (module.js:362:17)
at require (module.js:378:17)
at Object.<anonymous> (/usr/share/npm/lib/utils/ini.js:32:10)
   at Module._compile (module.js:449:26)
at Object.Module._extensions..js (module.js:467:10)
at Module.load (module.js:356:32)
at Function.Module._load (module.js:312:12)
at Module.require (module.js:362:17)

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