📝 Commit Details:

backend/node_modules/date-fns/docs/webpack.md

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+# webpack
+
+## Removing unused languages from dynamic import
+
+If a locale is imported dynamically, then all locales from date-fns are loaded by webpack into a bundle (~160kb) or split across the chunks. This prolongs the build process and increases the amount of space taken. However, it is possible to use webpack to trim down languages using [ContextReplacementPlugin].
+
+Let's assume that we have a single point in which supported locales are present:
+
+`config.js`:
+
+```js
+// `see date-fns/src/locale` for available locales
+export const supportedLocales = ["en-US", "de", "pl", "it"];
+```
+
+We could also have a function that formats the date:
+
+```js
+const getLocale = (locale) => import(`date-fns-locale/locale/${locale}.js`); // or require() if using CommonJS
+
+const formatDate = (date, formatStyle, locale) => {
+  return format(date, formatStyle, {
+    locale: getLocale(locale).default,
+  });
+};
+```
+
+In order to exclude unused languages we can use webpacks [ContextReplacementPlugin].
+
+`webpack.config.js`:
+
+```js
+import webpack from "webpack";
+import { supportedLocales } from "./config.js";
+
+export default config = {
+  resolve: {
+    alias: {
+      "date-fns-locale": path.dirname(require.resolve("date-fns/package.json")),
+    },
+  },
+  plugins: [
+    new webpack.ContextReplacementPlugin(
+      /date-fns[/\\]locale/,
+      new RegExp(`(${locales.join("|")})\.js$`),
+    ),
+  ],
+};
+```
+
+This results in a language bundle of ~23kb .
+
+[contextreplacementplugin]: https://webpack.js.org/plugins/context-replacement-plugin/