NextGlobeGen makes it effortless to deliver your content in multiple languages with SEO-optimized, localized URLs.

NextGlobeGen is a powerful TypeScript-first internationalization (i18n) library for Next.js App Router applications. Unlike traditional i18n solutions, NextGlobeGen uses generative programming to automatically create localized routes and type-safe APIs, giving you a seamless development experience with full TypeScript support.

Why NextGlobeGen?

🎯 Developer Experience First

• Zero Runtime Overhead - Routes are generated at build time, not runtime
• Type-Safe Everything - Full TypeScript inference for routes, locales, and messages
• Universal API - Same hooks and components work in both server and client components
• Hot Reloading - Changes to routes and messages regenerate automatically

🚀 Production Ready

• SEO Optimized - Automatic language alternate links and localized pathnames
• Performance - Code splitting support with filtered message delivery
• Flexible Routing - Support for prefix-based and domain-based locale routing
• Next.js Native - Built specifically for Next.js App Router with full feature support

💪 Powerful Features

• Automatic Key Extraction - Automatically discover translation keys from your source code
• ICU Message Format - Rich text formatting with plurals, dates, numbers, and embedded React components
• Localized Pathnames - Translate URL segments for better SEO (e.g., /en/about → /fi/tietoja)
• Smart Locale Detection - Automatic user locale negotiation with cookie persistence
• Dynamic Routes - Full support for dynamic segments, catch-all routes, and parallel routes

Quick Example

import { useTranslations, Link } from "next-globe-gen";

export default function HomePage() {
  const t = useTranslations();

  return (
    <div>
      <h1>{t("welcome")}</h1>
      <p>{t("description", { name: "NextGlobeGen" })}</p>
      <Link href="/dashboard">{t("dashboard.title")}</Link>
    </div>
  );
}

{
  "welcome": "Welcome!",
  "description": "{name} makes i18n effortless",
  "dashboard": {
    "title": "Dashboard"
  }
}

This automatically works for all configured locales with zero additional code!

Key Features

Generative Locale Routes

The plugin watches your src/_app directory and automatically generates localized versions of your routes in real-time:

src/_app/about/page.tsx  →  src/app/(i18n)/en/about/page.tsx
                         →  src/app/(i18n)/fi/tietoja/page.tsx

No manual route duplication. No runtime route matching. Just write your routes once, and NextGlobeGen handles the rest.

Type-Safe API

Get full TypeScript support across your entire i18n implementation:

// Routes are type-checked
<Link href="/blog/[slug]" params={{ slug: "hello" }}>
  Post
</Link>;

// Message keys are autocompleted
const t = useTranslations("dashboard");
t("title"); // ✓ Type-safe
t("typo"); // ✗ TypeScript error

// Locale switching with preserved params
const route = useRoute(); // Type: "/blog/[slug]"
const params = useParams<RouteParams<typeof route>>();
<Link href={route} params={params} locale="fi">
  Suomeksi
</Link>;

ICU Message Format

Support for rich text formatting with plurals, select, dates, and React components:

{
  "welcome": "Welcome {name}!",
  "posts": "{count, plural, =0 {No posts} one {One post} other {# posts}}",
  "updated": "Last updated: {date, date, long}",
  "richText": "Read <link>our guide</link> for more info"
}

t("welcome", { name: "Jon" });
t("posts", { count: 5 });
t("updated", { date: new Date() });
t("richText", { link: (children) => <Link href="/guide">{children}</Link> });

Automatic Key Extraction

NextGlobeGen automatically scans your source files and extracts translation keys, keeping your message files in sync with your code:

// Keys are automatically extracted from your source files
const t = useTranslations("home");
t("title"); // Extracted as "home.title"
t("welcome", { _defaultMessage: "Welcome!" }); // Extracted with default message

Configure extraction behavior in your config:

const config = {
  messages: {
    keyExtractionDirs: ["./src"], // Directories to scan
    pruneUnusedKeys: true, // Remove keys no longer in code
    whitelistedKeys: [/^dynamic\./], // Protect dynamic keys from pruning
  },
};

Flexible Routing Options

Choose the routing strategy that fits your needs:

Prefix-Based Routing (e.g., example.com/en, example.com/fi)

const config = {
  locales: ["en", "fi"],
  defaultLocale: "en",
  prefixDefaultLocale: true, // or false for root default locale
};

Domain-Based Routing (e.g., example.com, example.fi)

const config = {
  domains: [
    { domain: "example.com", locales: ["en"], defaultLocale: "en" },
    { domain: "example.fi", locales: ["fi"], defaultLocale: "fi" },
  ],
};

Smart Middleware

The included proxy/middleware handles:

• Locale Negotiation - Detects user's preferred language from Accept-Language header
• Cookie Persistence - Remembers user's language choice
• Alternate Links - Adds SEO-friendly language alternate links to response headers
• Domain Routing - Redirects users to the correct domain based on locale

Server & Client Components

The same API works everywhere:

// "use client"; just add this directive for Client Components
import { useLocale, useTranslations } from "next-globe-gen";

export default function ServerComponent() {
  const locale = useLocale();
  const t = useTranslations();
  return <h1>{t("title")}</h1>;
}

Need async functions? Use the get* aliases:

export async function generateMetadata() {
  const t = getTranslations();
  return { title: t("pageTitle") };
}

Getting Started

Ready to internationalize your Next.js app? Follow our Getting Started Guide to set up NextGlobeGen in minutes.

Coming from next-intl?

If you're familiar with next-intl or considering alternatives, check out our detailed comparison to understand the differences and see which approach fits your project best.