I Built a Lightweight i18n Library for JavaScript — Meet globaly-i18n

Rounak Sharrma — Sun, 15 Mar 2026 17:34:21 +0000

globaly-i18n
Lightweight internationalization (i18n) and translation library for JavaScript and TypeScript with support for namespaces, lazy loading, caching, middleware, language detection, CLI tools, and type-safe translations.

Designed to work seamlessly in frontend and backend applications, including Node.js, React, Vue, Next.js, Express, and NestJS.

npm version weekly downloads total downloads bundle size license typescript

✨ Features
🌍 Dynamic language loading
🗂 Namespace-based translations
🔑 Nested translation keys
🔢 Pluralization support
🔄 Variable interpolation
🔁 Fallback language support
🌐 Language switching
🧠 Language detection (browser / headers / query / localStorage)
💾 Language persistence
⚡ Translation caching for performance
📦 Lazy namespace loading
⚛ React hook support
🧩 Express & NestJS middleware support
🧠 TypeScript autocomplete for translation keys
🛠 CLI translation key extraction
🌐 CLI translation generator
⚡ Lightweight and fast
🖥 Works in Node.js, React, Vue, Next.js and other frameworks
📦 Installation
Install using npm:

npm install globaly-i18n
Using yarn:

yarn add globaly-i18n
Using pnpm:

pnpm add globaly-i18n
🚀 Quick Start
import { createI18n } from "globaly-i18n";

const i18n = await createI18n({
defaultLang: "en",
namespaces: ["common"],
loader: (lang, ns) =>
import(./locales/${lang}/${ns}.json).then((m) => m.default),
});

console.log(i18n.t("common:home.title", { name: "Rounak" }));
Output

Welcome Rounak
📁 Translation File Structure
Using namespaces allows you to organize translations by module.

locales
├ en
│ ├ common.json
│ └ auth.json
│
└ de
├ common.json
└ auth.json
📄 Example Translation File
locales/en/common.json
{
"home": {
"title": "Welcome {name}"
},
"cart": {
"items": {
"one": "You have {count} item",
"other": "You have {count} items"
}
}
}
🌐 Switching Languages
await i18n.setLanguage("de");

console.log(i18n.t("common:home.title", { name: "Rounak" }));
Output

Willkommen Rounak
🔢 Pluralization
i18n.t("common:cart.items", { count: 5 });
Output

You have 5 items
🔄 Variable Interpolation
i18n.t("common:home.title", {
name: "Rounak"
});
Output

Welcome Rounak
📦 Lazy Namespace Loading
For large applications you can load namespaces only when needed.

await i18n.loadNamespace("dashboard");

console.log(i18n.t("dashboard:stats.users"));
This keeps the initial bundle small and improves performance.

⚡ Translation Caching
globaly-i18n automatically caches translations internally.

Repeated calls like:

i18n.t("common:home.title");
are served from cache for better performance.

💾 Language Persistence
Selected language is automatically saved to localStorage.

await i18n.setLanguage("de");
After page reload, the language remains active.

🧠 Language Detection
Languages can be detected automatically from:

Browser settings
HTTP Accept-Language header
Query parameters (?lang=de)
localStorage
Example

const i18n = await createI18n({
defaultLang: "en",
detectLanguage: true,
namespaces: ["common"],
loader: (lang, ns) =>
import(./locales/${lang}/${ns}.json).then((m) => m.default)
});
⚛ React Integration
Wrap your application with the provider.

import { I18nProvider } from "globaly-i18n/react";

Use translations inside components.

import { useTranslation } from "globaly-i18n/react";

function Home() {
const { t, setLanguage } = useTranslation();

return (
<>

{t("common:home.title")}

setLanguage("de")}>
Switch Language

</>
);
}
🧩 Middleware (Express / NestJS)
import express from "express";
import { createI18n, i18nMiddleware } from "globaly-i18n";

const app = express();

const i18n = await createI18n({
defaultLang: "en",
namespaces: ["common"],
loader: (lang, ns) =>
import(./locales/${lang}/${ns}.json).then((m) => m.default)
});

app.use(i18nMiddleware(i18n));

app.get("/", (req, res) => {
res.send(req.t("common:home.title"));
});

app.listen(3000);
🛠 CLI Translation Key Extraction
Scan your project and extract translation keys.

Example source code

t("common:home.title");
t("auth:login.button");
Run

npx globaly-i18n extract src
🌐 CLI Translation Generator
Automatically generate translated files.

npx globaly-i18n translate --from en --to de,fr,es
Example output

locales
├ en
├ de
├ fr
└ es
🧠 TypeScript Support
globaly-i18n provides type-safe translation keys.

i18n.t("common:home.title"); // valid
i18n.t("common:home.titel"); // TypeScript error
📚 API
createI18n(options)
Creates a new i18n instance.

Option Type Description
defaultLang string Default language
fallbackLang string Fallback language
namespaces string[] Translation namespaces
detectLanguage boolean Enable language detection
loader function Function used to load translations
t(key, options)
i18n.t("common:home.title", { name: "Rounak" });
setLanguage(lang)
await i18n.setLanguage("de");
getLanguage()
i18n.getLanguage();
loadNamespace(namespace)
await i18n.loadNamespace("dashboard");
📚 Examples
Node.js Example
import { createI18n } from "globaly-i18n";

const i18n = await createI18n({
defaultLang: "en",
namespaces: ["common"],
loader: (lang, ns) =>
import(./locales/${lang}/${ns}.json).then((m) => m.default)
});

console.log(i18n.t("common:home.title"));
React Example
import { useTranslation } from "globaly-i18n/react";

function Example() {
const { t } = useTranslation();

return

{t("common:home.title")}

;
}
Express Example
app.get("/", (req, res) => {
res.send(req.t("common:home.title"));
});

globaly-i18n focuses on:

⚡ lightweight architecture
🧩 framework-agnostic design
🧠 TypeScript developer experience
🚀 simple integration
🔧 flexible usage for both frontend and backend
🧪 Testing
Run tests using

npm test
The project uses Vitest.

🔑 Keywords
internationalization • i18n • localization • translation • javascript • typescript • nodejs • express • nestjs • react i18n • nextjs i18n • multilingual • language detection • translation library • frontend i18n • backend i18n

📄 License
MIT License

⭐ Support
If you find this library useful:

⭐ Star the repository
📦 Share it with other developers
🐛 Report issues or suggest improvements

DEV Community: Rounak Sharrma

I Built a Lightweight i18n Library for JavaScript — Meet globaly-i18n

{t("common:home.title")}

{t("common:home.title")}