Internationalization

Codapult uses next-intl with cookie-based locale detection. Two locales ship out of the box — English (en) and Russian (ru) — and adding more takes just a few minutes.

How It Works

| Piece | Location | | ----------------- | ---------------------------------------------- | | Translation files | messages/en.json, messages/ru.json | | Locale config | src/i18n/request.ts | | Locale cookie | locale (set by the LocaleSwitch component) |

The active locale is read from the locale cookie on every request. If the cookie is missing or invalid, Codapult falls back to en.

Using Translations

Client Components

'use client';

import { useTranslations } from 'next-intl';

export function Greeting() {
  const t = useTranslations('dashboard');
  return <h1>{t('welcome')}</h1>;
}

Server Components

import { getTranslations } from 'next-intl/server';

export default async function Page() {
  const t = await getTranslations('dashboard');
  return <h1>{t('welcome')}</h1>;
}

Message File Structure

Messages are organized by namespace. Use nested keys for logical grouping:

{
  "dashboard": {
    "welcome": "Welcome back",
    "settings": "Settings",
    "members": "{count, plural, one {# member} other {# members}}"
  },
  "auth": {
    "signIn": "Sign in",
    "signUp": "Create account"
  }
}

Pluralization follows the ICU MessageFormat syntax — {count, plural, one {…} other {…}}.

Adding a New Locale

1. Create the message file — copy messages/en.json and translate:

cp messages/en.json messages/de.json

2. Register the locale in src/i18n/request.ts:

export const locales = ['en', 'ru', 'de'] as const;

3. Done. The LocaleSwitch component and cookie logic pick up the new locale automatically.

Locale Switcher

The LocaleSwitch component renders a dropdown that sets the locale cookie and reloads the page. It is included in the marketing header and the blog layout.

Blog Localization

Blog posts use a filename convention for translations:

| File | Locale | | ----------------------------- | -------------- | | content/blog/my-post.mdx | Default (en) | | content/blog/my-post.ru.mdx | Russian | | content/blog/my-post.de.mdx | German |

The blog utilities in src/lib/blog/ automatically discover available locales per post and populate the availableLocales field in metadata, so the UI can show a language switcher on each article.

If a post is not translated for the current locale, the reader sees the default-locale version.

Removing the i18n Module

If your product targets a single language, you can remove internationalization entirely via the setup wizard:

npx @codapult/cli setup

The wizard strips next-intl, the messages/ directory, the LocaleSwitch component, and all useTranslations / getTranslations calls — leaving plain strings in their place.