Webpack config to compile JS and Sass files. (In Visual Studio )Using "NPM Task Runner" to run "dev" script when project opens and "build" script before each build

package.json

{
  "name": "fullcalendar-core",
  "version": "1.0.0",
  "description": "",
  "main": "index.js",
  "scripts": {
    "dev": "webpack --watch",
    "build": "cross-env NODE_ENV=production webpack"
  },
  "author": "Esau Silva (@_esausilva)",
  "license": "MIT",
  "devDependencies": {
    "@babel/core": "^7.2.0",
    "@babel/preset-env": "^7.2.0",
    "babel-loader": "^8.0.4",
    "cross-env": "^5.2.0",
    "css-loader": "^1.0.1",
    "cssnano": "^4.1.7",
    "file-loader": "^2.0.0",
    "mini-css-extract-plugin": "^0.4.5",
    "node-sass": "^4.10.0",
    "postcss-loader": "^3.0.0",
    "postcss-preset-env": "^6.4.0",
    "sass-loader": "^7.1.0",
    "webpack": "^4.26.1",
    "webpack-cli": "^3.1.2"
  },
  "browserslist": [
    ">0.25%",
    "not dead",
    "not ie <= 10",
    "not op_mini all"
  ],
  "-vs-binding": {
    "BeforeBuild": [
      "build"
    ],
    "ProjectOpened": [
      "dev"
    ]
  }
}

webpack.config.js

const path = require('path');
const MiniCssExtractPlugin = require('mini-css-extract-plugin');
const postcssPresetEnv = require('postcss-preset-env');

const devMode = process.env.NODE_ENV !== 'production';

module.exports = {
    mode: devMode ? 'development' : 'production',
    entry: ['./Scripts/calendar.js','./Styles/calendar.scss'],
    output: {
        path: path.resolve(__dirname, 'wwwroot'),
        publicPath: '/',
        filename: devMode ? 'js/calendar.js' : 'js/calendar.min.js'
    },
    module: {
        rules: [
            {
                test: /\.(js)$/,
                exclude: /node_modules/,
                use: {
                    loader: 'babel-loader',
                    options: {
                        presets: ['@babel/preset-env']
                    }
                }
            },
            {
                test: /\.(sa|sc)ss$/,
                use: [
                    {
                        loader: MiniCssExtractPlugin.loader
                    },
                    {
                        loader: 'css-loader',
                        options: {
                            importLoaders: 2
                        }
                    },
                    {
                        loader: 'postcss-loader',
                        options: {
                            ident: 'postcss',
                            plugins: devMode
                                ? () => []
                                : () => [
                                    postcssPresetEnv({
                                        browsers: ['>0.25%', 'not dead', 'not ie <= 10','not op_mini all']
                                    }),
                                    require('cssnano')()
                                ]
                        }
                    },
                    {
                        loader: 'sass-loader'
                    }
                ]
            },
            {
                test: /\.(png|jpe?g|gif)$/,
                use: [
                    {
                        loader: 'file-loader',
                        options: {
                            name: '[name].[ext]',
                            publicPath: '../images',
                            emitFile: false
                        }
                    }
                ]
            }
        ]
    },
    plugins: [
        new MiniCssExtractPlugin({
            filename: devMode ? 'css/calendar.css' : 'css/calendar.min.css'
        })
    ]
};