1.1.0: R2 storage, media preconnect/normalization, favicon + SEO structured data, x-default hreflang

src/modules/seo/hreflang.ts

@@ -1,6 +1,6 @@
 import type { I18nConfig, LocalizedSlugs } from '../i18n/index.js'
 
-import { buildLocalizedPath, getLocaleCodes } from '../i18n/index.js'
+import { buildLocalizedPath, getDefaultLocale, getLocaleCodes } from '../i18n/index.js'
 
 type BuildHreflangArgs = {
   /** Absolute site origin, e.g. 'https://example.com'. Omit for relative paths. */
@@ -19,20 +19,28 @@ type BuildHreflangArgs = {
 }
 
 /**
- * Builds a map of locale → URL for hreflang alternate links, suitable for
  * Next.js Metadata `alternates.languages`.
  *
  * Bridges SEO and i18n: for each configured locale that the document has a
  * slug in, it produces the locale-aware path (via buildLocalizedPath),
  * optionally prefixed with an absolute origin.
  *
+ * Also emits `x-default` pointing at the default locale — the version Google
+ * serves when the user's language/region matches no hreflang, and the fallback
+ * when the root ('/') redirect is ambiguous (Googlebot with no/foreign
+ * Accept-Language).
+ *
  * @example
  * buildHreflangAlternates({
  *   slugs: { pl: 'o-nas', en: 'about' },
  *   config,
  *   baseUrl: 'https://example.com',
  * })
- * // → { pl: 'https://example.com/pl/o-nas', en: 'https://example.com/en/about' }
+ * // → {
+ * //   pl: 'https://example.com/pl/o-nas',
+ * //   en: 'https://example.com/en/about',
+ * //   'x-default': 'https://example.com/pl/o-nas',
+ * // }
  */
 export function buildHreflangAlternates({
   baseUrl,
@@ -51,5 +59,15 @@ export function buildHreflangAlternates({
     }
   }
 
+  // x-default: the version Google serves when the user's language/region doesn't
+  // match any hreflang — and, crucially here, the fallback when the root ('/')
+  // redirect is ambiguous (Googlebot with no/foreign Accept-Language). Point it
+  // at the default locale (the primary market) so search shows that version by
+  // default instead of guessing. Only set when the default locale has a URL.
+  const defaultLocalePath = alternates[getDefaultLocale(config)]
+  if (defaultLocalePath) {
+    alternates['x-default'] = defaultLocalePath
+  }
+
   return alternates
 }