I18n

Internationalization — i, eighteen letters, n — designing a product so that it can be adapted to any language and region without changing the code: strings out of the templates and into message files, dates, numbers and plurals formatted by locale, layouts that survive text that is twice as long or reads right to left

Its partner is l10n, localization: the act of adapting for one locale, which i18n makes possible. This site runs on @nuxtjs/i18n with five locales (en, es, fr, de, kn), prefix_except_default routing so English is unprefixed and the locale lives in the route, message files under i18n/locales/, and one translated collection per locale that has one — guidesEs, guidesDe — with an English fallback and a disclaimer when it fell back or the translation is machine-made. A locale-messages test keeps every key present in all five files, because a missing key leaves a screen reader announcing an English control.