intermediate

Internationalization

Locale-aware routing, formatting, pluralization, and right-to-left basics for products that serve multiple languages and regions.

Internationalization interviews test locale architecture: routing, hreflang, message catalogs, date/number formatting, plural grammar, and RTL layout—before translation quality alone.

Subtopics: locale routing, date/time formatting, number formatting, plurals, RTL basics.

On interviews: design `/en` and `/de` URL policy; format currency in checkout; fix a broken plural in Russian; mirror layout for Arabic.

Common pitfalls: concatenated sentences; English plural rules; physical left/right CSS; geo-IP language forcing.

The trade-off is translator and engineering process overhead versus credible global product UX.

Checklist:

Stable URLs and hreflang per locale.
ICU-style messages for grammar.
Intl APIs for numbers and dates.
Logical CSS and `dir` for RTL markets.