Rails YAML, with the locale root written for you

The root key is the language, and it has to change on the way out

Rails wraps a whole locale file in one top-level key: en: in the English file, cs: in the Czech one. Copy the English file, translate every value and forget the root, and Rails loads your Czech strings as a second copy of English.

Linguiqo reads the root key as the language rather than as part of every key, so cart.empty in en.yml and cart.empty in cs.yml are recognised as the same string. On export the root is written as the language being exported, spelled the way your file spells it: pt-BR stays pt-BR.

A file whose single top-level key is not a language, such as app: in a Symfony catalogue, keeps that key exactly as it was.

Nested keys become one address per string

Each nested level turns into a dot, so the translator sees checkout.cart.empty, the same name your code passes to t(). On export the dots become nesting again, and a list stays a list: errors: [First, Second] comes back as a list, not as a hash keyed 0 and 1.

Long values are never wrapped across lines, and accented characters are written as themselves rather than as escape sequences, so the file stays readable in a diff.

Interpolations are checked, not just copied

A translation that drops %{count} or renames %{name} to %{nom} renders a literal placeholder or raises at runtime. Linguiqo recognises Rails interpolation as a placeholder, and the quality checks flag a translation whose placeholders do not match the source.