Babel

For compiling React, first install the Babel React preset module as a development dependency:

npm install babel-preset-react --save-dev

Then, update .babelrc to include the module and also configure the react-hot-loader Babel plugin as required for the react-hot-loader module.

mern-skeleton/.babelrc:

{
    "presets": [
      "env",
      "stage-2",
      "react"
    ],
    "plugins": [
      "react-hot-loader/babel"
    ]
}