npm install won't install devDependencies

Question

On windows for some reason when I run npm install it won't install devDependencies. AFAIK it should. If I run npm install --dev devDependencies are installed. I don't understand why npm install doesn't install devDependencies too, but installs only dependencies. What could be the reason? How can I fix it?

Maybe something is wrong with my package.json? It is listed below if it may be helpful:

{
  "name": "try-brunch",
  "version": "0.1.0",
  "private": "true",
  "devDependencies": {
    "brunch": "^2.0.4",
    "cssnano-brunch": "^1.1.5",
    "javascript-brunch": "^1.8.0",
    "sass-brunch": "^1.9.2",
    "uglify-js-brunch": "^1.7.8"
  },
  "dependencies": {
    "jquery": "^2.1.4"
  }
}

Why do we even need a fix for it? It should be the default! devDependencies are literally dependencies for the developers of the module. I bet most of us npm install a module to use it, rather than develop it. — Константин Ван
Say you write an app, and you need a logger or webpack plugin. those are devdeps. those need to be installed. npm doesn't install those in some cases. — Tristan Tzara
I mean, the installation for devDependencies is needed only when you write the package (application). Using it does not require the devDependencies. So it is reasonable for devDependencies to require extra flags to be installed. If npm install installed devDependencies by default, the users would get redundant packages as well. — Константин Ван
the documented behaviour is that when I do npm i in my folder it grabs py package.json and installs both deps and devdeps. This is the way it's intended to work and it makes sense (e.g. when I do npm i after git clone I expect to have all I need, including e.g. webpack plugins). This question addresses a bug, when the actual behaviour is different from intended. pls, take a look at docs - docs.npmjs.com/cli/install . There's a flag to not install devdeps, but the default behavior is to install them, which makes perfect sense and is what everybody expects — Tristan Tzara
I don't see any sane reasons to make me remember to run another command to install e.g. webpack plugins or typescript type defs or any other devdeps every time I pull. npm i should bootstrap both, which is the intended, sane and documented behavior, so I honestly don't understand why you say that this issue should be a standard — Tristan Tzara

arcseldon arcseldon · Accepted Answer · 2016-01-11T10:41:23

Check the NPM docs for install

With the --production flag (or when the NODE_ENV environment variable is set to production), npm will not install modules listed in devDependencies."

The --only={prod[uction]|dev[elopment]} argument will cause either only devDependencies or only non-devDependencies to be installed regardless of the NODE_ENV."

Have you tried

npm install --only=dev

If you are worried that your package.json might be incorrect, best thing to do is this. Create a new folder, and run:

npm init --yes

Then:

npm install --save-dev brunch@^2.0.4
npm install --save-dev cssnano-brunch@^1.1.5
npm install --save-dev javascript-brunch@^1.8.0
npm install --save-dev sass-brunch@^1.9.2
npm install --save-dev uglify-js-brunch@^1.7.8
npm install jquery@^2.1.4 --save

And you should be good to go! Otherwise, will keep posting other options.

Check your npm configuration:

npm config list

npm gets its config settings from the command line, environment variables, and npmrc files. So check environment variables, and the npmrc file.

Still failing?

Ok, create a new folder, ideally somewhere else on your filesystem. ie. not in same folder hierarchy. For instance, C:\myNewFolder - the closer to the base C: drive the better.

Then run:

npm init --yes

Now run:

npm install underscore --save

and finally:

npm install mocha --save-dev

Does everything work as expected?

What I am trying to do is understand whether your problem is global, or something local to the previous folder and dependencies.

npm install won't install devDependencies

10 Answers