Add a language

Rezepte's interface is available in English and German. Adding another language takes no programming and four files: you name the language in one line, translate a copy of the English texts, list the words recipes in your language use so importing a recipe understands them, and register that list in one more line. Two commands generate the rest. Your recipes are not affected — Rezepte never translates recipe content.

What you need

A clone of the repository.
mise, which installs every other tool the project uses. Run mise run setup once in the clone.

Steps

Name the language

Add its language code to locales in service/internal/i18n/locales.json — for French, fr:

{
	"baseLocale": "en",
	"locales": ["en", "de", "fr"]
}

Leave baseLocale as it is. English is what every text falls back to.

Translate the texts

Copy frontend/messages/en.json to frontend/messages/fr.json (with your language's code) and translate every value on the right-hand side:

"overview_headline": "Que cuisine-t-on aujourd'hui ?",

Keep every key on the left exactly as it is.
Keep every placeholder in curly braces, such as {count} or {name}, exactly as it is. You can move it within the sentence.
editor_unit_options is not a sentence but the units the recipe editor suggests, separated by commas. Do not translate the English list word for word: write the units a cook in your language actually uses, in their usual abbreviations, as many or as few as fit. German, for example, has TL, EL, Bund and Zehe and no cup.
time_units_seconds, time_units_minutes and time_units_hours are not sentences but the words for seconds, minutes and hours, separated by |, and time_words_range and time_words_and are the words in "10 to 15 minutes" and "1 hour and 20 minutes". The recipe editor uses them to spot the times in a step. Write every spelling and abbreviation a recipe in your language uses, with full words first: German has Minuten|Minute|Min.|Min.
import_example is an example recipe, not a sentence. Translate it using the headings (the "Ingredients" and "Method" equivalents) that your language's word list in lang_xx.go knows: mise run check imports it and fails otherwise.
Translate every entry. The check in the next step fails on any that are missing, so the interface never shows a half-translated screen.

The mails Rezepte sends take their texts from the same file — the keys starting with mail_ — so translating them translates the mails too.

The language picker names the language by itself, in the reader's language and in its own ("French · Français"), so there is nothing to add for that.

List the recipe words

Copy service/internal/recipeimport/lang_en.go to lang_fr.go (with your language's code) and replace the English words with your language's: the units cooks write after an amount ("EL", "Prise"), the headings above ingredients and steps ("Zutaten", "Zubereitung"), words like "to taste" that make an amount vague, and the others the comments in service/internal/recipeimport/lang.go explain. Then add french to the list languages in lang.go. The check in the next step fails while a language has no such list. If writing the tests for it is new to you, say so in the pull request and a maintainer adds them.

Check and look at it

mise run //service:generate
mise run check
mise run //docs/user:openapi
RZP_DEMO_LOCALE=fr mise run demo

The first command copies the mail texts of your file to service/internal/mail/messages/fr.json, where the service reads them; without it mise run check fails, naming your language's embedded copy as stale. mise run check finds missing texts and placeholders. The third command updates the API reference, which lists the languages the API accepts. The fourth starts a demo instance at the address it prints; log in as demo / demo1234 and the interface is in your language. The demo recipes stay English unless your language has sample recipes of its own, which is optional; those get simple placeholder images instead of photos.

Contribute it

Open a pull request with the two new files (fr.json and lang_fr.go), the lines in locales.json and lang.go, the generated service/internal/mail/messages/fr.json and the updated API reference. A translation can be improved later like any other change.