Windows machine 'NODE_ENV' is not recognized as an internal or external command,

[Sensiblemnd]

When doing a yarn build

'NODE_ENV' is not recognized as an internal or external command,

[Sensiblemnd]

Fix:
yarn add -D cross-env
in package json

"build": "cross-env NODE_ENV=production webpack --config config/webpack.prod.js",
"build-staging": "cross-env NODE_ENV=production webpack --config config/webpack.stag.js",

[stefanwuthrich]

tks @Sensiblemnd
If you want, you can add a pull request or tell me to do