webpack.config.dev.js

const HtmlWebpackPlugin = require("html-webpack-plugin");
const path = require("path");

module.exports = {
    devtool: "eval",
    entry: {
        demo: "./source/demo/index",
    },
    output: {
        path: path.join(__dirname, "build"),
        filename: "static/[name].js",
    },
    plugins: [
        new HtmlWebpackPlugin({
            filename: "index.html",
            inject: true,
            template: "./index.html",
        }),
    ],
    module: {
        rules: [
            {
                test: /\.js$/,
                use: ["babel-loader"],
                include: path.join(__dirname, "source"),
            },
            {
                test: /\.css$/,
                use: ["style-loader", "css-loader?modules", "postcss-loader"],
                include: path.join(__dirname, "source"),
            },
            {
                test: /\.css$/,
                use: ["style-loader", "css-loader"],
                include: path.join(__dirname, "styles.css"),
            },
        ],
    },
    devServer: {
        contentBase: "build",
        port: 3001,
    },
};