meta: reduce middleware invocations by only running on /

middleware.ts

···
 
   // Used when no locale matches
   defaultLocale: defaultLocale.code,
+
+  // Always use a Locale as a prefix for routing
+  localePrefix: 'always',
+
+  // We already have our own way of providing alternate links
+  // generated on `next.dynamic.mjs`
+  alternateLinks: false,
 });
 
-export const config = {
-  // Note.: This needs to be updated when activating more locales
-  // Format: '/(locale1|locale2|locale3|...)/:path*'
-  matcher: ['/', '/(en)/:path*'],
-};
+// We only want the middleware to run on the `/` route
+// to redirect users to their preferred locale
+export const config = { matcher: ['/'] };

next.dynamic.mjs

···
       : siteConfig.title;
 
     pageMetadata.twitter.title = pageMetadata.title;
-    pageMetadata.alternates.canonical = `${baseUrlAndPath}/${locale}/${path}`;
 
-    pageMetadata.alternates.languages[
-      'x-default'
-    ] = `${baseUrlAndPath}/${defaultLocale.code}/${path}`;
+    const getUrlForPathname = (l, p) =>
+      `${baseUrlAndPath}/${l}${p ? `/${p}` : ''}`;
+
+    pageMetadata.alternates.canonical = getUrlForPathname(locale, path);
+
+    pageMetadata.alternates.languages['x-default'] = getUrlForPathname(
+      defaultLocale.code,
+      path
+    );
 
     availableLocaleCodes.forEach(currentLocale => {
-      pageMetadata.alternates.languages[
-        currentLocale
-      ] = `${baseUrlAndPath}/${currentLocale}/${path}`;
+      pageMetadata.alternates.languages[currentLocale] = getUrlForPathname(
+        currentLocale,
+        path
+      );
     });
 
     return pageMetadata;