How to set NODE_ENV to production/development in OS X

Before running your app, you can do this in console,

export NODE_ENV=production

Or if you are in windows you could try this:

SET NODE_ENV=production

for PowerShell:

$env:NODE_ENV="production"

or you can run your app like this:

NODE_ENV=production node app.js

You can also set it in your js file:

process.env.NODE_ENV = 'production';

But I don't suggest to do it in your runtime file, since it's not easy to open up VIM in your server and change it to production. You can make a config.json file in your directory and everytime your app runs, it reads from it and sets the configuration.

in package.json:

{
  ...
  "scripts": {
    "start": "NODE_ENV=production node ./app"
  }
  ...
}

then run in terminal:

npm start