webpack config that works with both `SASS` => `CSS` file and hot loading the css within the `webpack-dev-server` watching for changes

tools--webpack.config.dev.babel.js

import merge from 'webpack-merge';
import baseConfig from './../webpack.config.babel.js';
import path from 'path';


const ROOT_PATH = path.resolve(
  path.join(__dirname, '/../')
);

module.exports = merge(baseConfig, {
  output: {
    filename: 'dasher.js',
    path: path.join(__dirname, '/public'),
  },
  module: {
    loaders: [
      {
        test: /\.scss$/,
        loaders: [
          'style-loader',
          'css-loader',
          'sass-loader',
        ],
      },
    ],
  },
  devServer: {
    inline: true,
    contentBase: 'public',
  },
  watch: true,
});

tools--webpack.config.prod.js

import merge from 'webpack-merge';
import baseConfig from './../webpack.config.babel.js';
import CopyWebpackPlugin from 'copy-webpack-plugin';
import ExtractTextPlugin from 'extract-text-webpack-plugin';
import path from 'path';

const PROJECT_ROOT = path.resolve('.');

module.exports = merge(baseConfig, {
  output: {
    filename: 'dasher.js',
    path: path.join(PROJECT_ROOT, '/build/asset'),
  },
  module: {
    loaders: [
      {
        test: /\.scss$/,
        loader: ExtractTextPlugin.extract(
          'css-loader',
          'sass-loader'
        ),
      },
    ],
  },
  plugins: [
    new ExtractTextPlugin({
      filename: './style.css',
      allChunks: true,
    }),
    new CopyWebpackPlugin([
      {
        from: path.join(PROJECT_ROOT, '/public/'),
        to: path.join(PROJECT_ROOT, '/build/'),
      }
    ]),
  ],
});

webpack.config.babel.js

import webpack from 'webpack';
import FlowStatusWebpackPlugin from 'flow-status-webpack-plugin';
import ExtractTextPlugin from 'extract-text-webpack-plugin';
import path from 'path';


module.exports = {
  entry: path.join(__dirname, '/src/app.js'),
  target: 'web',
  module: {
    loaders: [
      {
        test: /\.(js|jsx)$/,
        include: path.join(__dirname, '/src'),
        exclude: path.join(__dirname, '/node_modules/'),
        loaders: [
          'babel-loader',
        ],
      },
    ],
  },
  plugins: [
    new webpack.NoEmitOnErrorsPlugin(),
    new FlowStatusWebpackPlugin({
      restartFlow: true,
      failOnError: true,
    }),
  ],
  resolve: {
    extensions: ['.js', '.jsx'],
  },
};