Why is process.env.NODE_ENV undefined?

javascript, node.js

Solution

`process.env` is a reference to your environment, so you have to set the variable there.

To set an environment variable in Windows:

SET NODE_ENV=development

on macOS / OS X or Linux:

export NODE_ENV=development

Problem

I'm trying to follow a tutorial on NodeJS. I don't think I missed anything but whenever I call the `process.env.NODE_ENV` the only value I get back is `undefined`. According to my research the default value should be `development`. How is this value dynamically set and where is it set initially?

Original source

Related problems