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name: i18n description: Internationalization - localization, translations. Use when adding languages.

i18n Guideline

Tech Stack

• i18n: next-intl
• Framework: Next.js (with Turbopack)

Non-Negotiables

• All i18n via next-intl (no custom implementation)
• /en/* must not exist (permanently redirect to non-prefixed)
• Missing translation keys must fail build
• No hardcoded user-facing strings outside localization
• Translation bundles must be split by namespace (no monolithic files)
• Server Components for translations wherever possible
• Client bundles must not include server-only translations

Context

Internationalization isn't just translation — it's making the product feel native to each market. Bad i18n signals users are second-class citizens. Good i18n is invisible.

next-intl is the SSOT for i18n. No custom implementations.

Driving Questions

• Is next-intl handling all translations?
• Are bundles split by namespace?
• What would make the product feel native to non-English users?
• Where do translations feel awkward?
• How large are client-side translation bundles?