Internationalization

The template ships bilingual (English + Chinese) using next-intl. Locale is part of the URL via the [locale] segment, messages are JSON catalogs, and src/proxy.ts handles detection and redirects.

Important files

Routing

export const routing = defineRouting({
  locales: ["en", "zh"],
  defaultLocale: "en",
  localePrefix: "as-needed",
});

localePrefix: "as-needed" means the default locale is unprefixed and other locales carry their code:

request.ts reads the resolved locale, falls back to the default for unknown values, and imports the matching messages/{locale}.json.

Using translations & navigation

In components, pull strings with next-intl's hooks/helpers (useTranslations, getTranslations) keyed against messages/*.json. For any internal navigation, import from src/i18n/navigation.ts rather than next/link so the active locale is preserved:

export const { Link, redirect, usePathname, useRouter } =
  createNavigation(routing);

Detection & redirects: src/proxy.ts

proxy.ts runs next-intl's middleware first to detect and prefix the locale, then applies the protected-path check. Its matcher excludes API routes, Next internals, and files with extensions:

export const config = {
  matcher: ["/((?!api|_next|_vercel|.*\\..*).*)"],
};

API routes are skipped explicitly, so /api/* is never locale-prefixed. See Project Structure for the full request flow.

Adding a locale

Documentation locales (Fumadocs)

Docs are bilingual too, configured in src/lib/source.ts:

export const source = loader({
  baseUrl: "/docs",
  source: docs.toFumadocsSource(),
  i18n: { defaultLanguage: "en", languages: ["en", "zh"] },
});

Each doc ships as a filename pair: slug.mdx (English) and slug.zh.mdx (Chinese) — for the section index it's index.mdx / index.zh.mdx. Fumadocs resolves the right file from the request locale.

Related pages