Laravel Mix "sh: 1: cross-env: not found error" : <p>I have been trying to setup laravel mix on my project and followed the install guide on the laravel website however keep getting errors.</p>

<p>My package.json file is</p>

<pre><code>{
  "private": true,
  "scripts": {
    "dev": "cross-env NODE_ENV=development webpack --progress --hide-modules",
    "watch": "cross-env NODE_ENV=development webpack --watch --progress --hide-modules",
    "hot": "cross-env NODE_ENV=development webpack-dev-server --inline --hot",
    "production": "cross-env NODE_ENV=production webpack --progress --hide-modules"
  },
  "devDependencies": {
    "axios": "^0.15.2",
    "bootstrap-sass": "^3.3.7",
    "jquery": "^3.1.0",
    "laravel-mix": "^0.4.0",
    "lodash": "^4.16.2",
    "vue": "^2.0.1"
  },
  "name": "Code",
  "version": "1.0.0",
  "main": "webpack.mix.js",
  "directories": {
    "test": "tests"
  },
  "dependencies": {
    "ansi-regex": "^2.1.1",
    "ansi-styles": "^2.2.1",
    "axios": "^0.15.3",
    "babel-core": "^6.24.1",
    "babel-code-frame": "^6.22.0",
    "babel-generator": "^6.24.1",
    "babel-messages": "^6.23.0",
    "babel-helpers": "^6.24.1",
    "babel-register": "^6.24.1",
    "babel-template": "^6.24.1",
    "babylon": "^6.17.0",
    "balanced-match": "^0.4.2",
    "babel-runtime": "^6.23.0",
    "babel-types": "^6.24.1",
    "babel-traverse": "^6.24.1",
    "brace-expansion": "^1.1.7",
    "bootstrap-sass": "^3.3.7",
    "chalk": "^1.1.3",
    "convert-source-map": "^1.5.0",
    "concat-map": "^0.0.1",
    "core-js": "^2.4.1",
    "cross-env": "^3.2.4",
    "detect-indent": "^4.0.0",
    "esutils": "^2.0.2",
    "escape-string-regexp": "^1.0.5",
    "follow-redirects": "^1.0.0",
    "globals": "^9.17.0",
    "has-ansi": "^2.0.0",
    "home-or-tmp": "^2.0.0",
    "is-finite": "^1.0.2",
    "invariant": "^2.2.2",
    "json5": "^0.5.1",
    "js-tokens": "^3.0.1",
    "jquery": "^3.2.1",
    "jsesc": "^1.3.0",
    "laravel-mix": "^0.4.0",
    "lodash": "^4.17.4",
    "loose-envify": "^1.3.1",
    "mkdirp": "^0.5.1",
    "minimatch": "^3.0.3",
    "minimist": "^0.0.8",
    "number-is-nan": "^1.0.1",
    "os-homedir": "^1.0.2",
    "os-tmpdir": "^1.0.2",
    "path-is-absolute": "^1.0.1",
    "private": "^0.1.7",
    "regenerator-runtime": "^0.10.3",
    "repeating": "^2.0.1",
    "slash": "^1.0.0",
    "source-map": "^0.5.6",
    "source-map-support": "^0.4.14",
    "strip-ansi": "^3.0.1",
    "trim-right": "^1.0.1",
    "to-fast-properties": "^1.0.2",
    "vue": "^2.3.0"
  },
  "keywords": [],
  "author": "",
  "license": "ISC",
  "description": ""
}
</code></pre>

<p>and the error I am getting when I run any npm run command is</p>

<pre><code>&gt; Code@1.0.0 dev /home/vagrant/Code
&gt; cross-env NODE_ENV=development webpack --progress --hide-modules

sh: 1: cross-env: not found

npm ERR! Linux 4.4.0-51-generic
npm ERR! argv "/usr/local/bin/node" "/usr/local/bin/npm" "run" "dev"
npm ERR! node v7.8.0
npm ERR! npm  v4.2.0
npm ERR! file sh
npm ERR! code ELIFECYCLE
npm ERR! errno ENOENT
npm ERR! syscall spawn
npm ERR! Code@1.0.0 dev: `cross-env NODE_ENV=development webpack --progress --hide-modules`
npm ERR! spawn ENOENT
npm ERR!
npm ERR! Failed at the Code@1.0.0 dev script 'cross-env NODE_ENV=development webpack --progress --hide-modules'.
npm ERR! Make sure you have the latest version of node.js and npm installed.
npm ERR! If you do, this is most likely a problem with the Code package,
npm ERR! not with npm itself.
npm ERR! Tell the author that this fails on your system:
npm ERR!     cross-env NODE_ENV=development webpack --progress --hide-modules
npm ERR! You can get information on how to open an issue for this project with:
npm ERR!     npm bugs Code
npm ERR! Or if that isn't available, you can get their info via:
npm ERR!     npm owner ls Code
npm ERR! There is likely additional logging output above.

npm ERR! Please include the following file with any support request:
npm ERR!     /home/vagrant/.npm/_logs/2017-04-28T17_24_11_458Z-debug.log
</code></pre>

<p>I am running my project in a vagrant box and I am running laravel 5.4.</p>
