Localization & RTL

Cartisto is multilingual first. Themes must render correctly in both LTR and RTL (Arabic is a first-class target).

How strings layer

Storefront strings come from two layers, deep-merged at request time:

1. Base — a shared platform locale used by every theme.
2. Theme override — locales/<lang>.json in your theme, layered on top.

Override only the keys you want to change; you don’t redefine a whole branch.

// locales/en.json
{ "product": { "addToCart": "Add to bag" } }

Read strings with the t filter (pluralization + interpolation) or as an object ({{ t.product.addToCart }}).

The i18n completeness gate

The Quality Gate fails a publish if your locales disagree on keys — every language must define the same set. This catches a string translated in en but forgotten in ar before it ships.

RTL rules

• Use logical CSS (margin-inline-start, padding-inline-end, inset-inline) rather than left/right where direction matters.
• Read isRTL in templates when you must branch, and set dir from the language (the platform layout handles the document dir).
• The RTL gate loads your pages under dir=rtl at mobile/tablet/desktop and fails on any horizontal overflow — so a component that breaks the layout in Arabic can’t ship.