nodemon, babel-node: how to set environment variable?

You can add a "nodemonConfig" property to package.json with your env info. Then execute nodemon in your scripts section.

"nodemonConfig": {
  "restartable": "rs",
  "ignore": [
  "node_modules/**/node_modules"
  ],
  "delay": "2500",
  "env": {
    "NODE_ENV": "development",
    "NODE_CONFIG_DIR": "./config"
  }
}

I normally use the dotenv module on my projects.

We just need to create a .env file and require the dotenv module in our project:

.env file:

 __DEV__="true"

your-script.js file:

require('dotenv').config();

console.log(process.env.__DEV__)

Creating .env files is normally a good option since we can prevent to commit our environment files using .gitignore

For windows: set DEV = true&&nodemon -w src --exec "babel-node src --presets es2015,stage-0"