14 comments. By default, webpack 4 will look for a src / index. Later, I took my initial webpack.connfig.js and started to add the changes step by step too see when the source maps finally started to work. This plugin adds the “HMR runtime” into your bundle. The entry point tells webpack which module it should use to start building its internal dependency graph. To see the results, you need to use this plug-in to run webpack twice: the first build will take normal time. Change #3: Run WebpackDevServer with the hot: true option. Change #2: Add the HotModuleReplacementPlugin to your your webpack.config.js, like this: plugins: [new webpack.HotModuleReplacementPlugin()]; For a complete example, see the starter project webpack.config.js. Its main purpose is to bundle JavaScript files for usage in a browser, yet it is also capable of transforming, bundling, or packaging just about any resource or asset. If we don’t use this it does a full refresh of the page instead of hot module replacement. The webpack-dev-server is a little node.js Express server, which uses the [[webpack-dev-middleware]] to serve a webpack bundle.It also has a little runtime which is connected to the server via Socket.IO.The server emits information about the compilation state to the client, which reacts to those events. Webpack is a module bundler for modern JavaScript applications. Webpack-dev-server exposes itself and the Express server as a Node module. webpack.HotModuleReplacementPlugin, to provide some information about connections between modules. Add two configs: webpack.config.dev.js; webpack.config.prod.js HotModuleReplacementPlugin ({// Options...}) 选项(Options) 包含如下选项： multiStep (boolean)：设置为 true 时，插件会分成两步构建文件。首先编译热加载 chunks，之后再编译剩余的通常的资源。 fullBuildTimeout (number)：当 multiStep 启用时，表示两步构建之间的延时。 The Next.js framework abstracts away webpack for you, but it still uses webpack under the hood. This documentation corresponds to v6 of webpack-chain, which Neutrino utilizes. Now I'm getting this error, other answers haven't helped so much. From this module, webpack can infer which other modules or libraries the application depends on and include them in your bundle. The webpack.HotModuleReplacementPlugin enables support for Hot Module Replacement (HMR) on the webpack side of things. So, instead of creating its own HTML file, Webpack instead uses our HTML file - public/index.html and adds the bundled files to it via