Quick Tutorial: How to install your Javascript projects on your own computer

Hello Everyone,

I have been trying to learn how to install my *nix command projects on my computer so I can use them. I just did so with my own cat.js project so I’ll use that as an example.

  1. Your script needs to be in its own directory, with a package.json. All of you packages should be installed.
    | _ node_modules
    | _ package.json
    | _ package-lock.json
    | _ cat.js
  1. My package.json was set up like the following:
  "name": "catjs",
  "version": "1.0.0",
  "description": "javascript implementation of 'cat' bash command",
  "main": "cat.js",
  "dependencies": {
    "command-line-args": "^5.0.2",
    "command-line-usage": "^5.0.5"
  "bin": {
    "catjs": "./cat.js"
  "author": "Zach Berwaldt",
  "license": "ISC"

the "bin" field is so the catjs command maps to my script.

  1. At the top of your script. In my case `cat.js’ you put the following:
#!/usr/bin/env node

const commandLineArgs = require('command-line-args');
const commandLineUsage = require('command-line-usage');
const fs = require('fs');

const optionDefinitions = [
    { name: 'help', alias: 'h', type: Boolean, description: '' },

The #!/usr/bin/env node is called a shebang. Basically it makes the file be read as an executable.

  1. Finally install your command: npm install -g. Do the previous command while in the directory of your project or if your outside: npm install -g ./your-dir.

I am on Windows 10, and the above worked for me.

I also read about: npm link which supposedly does the same as npm install but you can continue to develop your cli and you won’t have to reinstall. I haven’t tried it myself so I can’t vouch for it.

Here is the documentation for that: https://docs.npmjs.com/cli/link


Nice! Good work figuring that out. I didn’t even bother doing that. :wink: