Xcode String Catalog localization with AI

What it is

String Catalogs (.xcstrings) replaced .strings and .stringsdict in Xcode 15. One file holds the source language, every translation, per-string comments and plural or device variations.

Example

{  "sourceLanguage": "en",  "strings": {    "%lld photos": {      "comment": "Album subtitle",      "localizations": {        "en": {          "variations": {            "plural": {              "one": { "stringUnit": { "state": "translated", "value": "%lld photo" } },              "other": { "stringUnit": { "state": "translated", "value": "%lld photos" } }            }          }        }      }    }  },  "version": "1.0"}

How Glossa handles it

Plurals

Plural variations are read as plural entries and written back as plural variations.

Comments and context

The comment field becomes the unit's context; Xcode-extracted comments therefore reach the translator automatically.

Placeholders

Format specifiers (%@, %lld, %1$@) are protected and checked on every translation.

Round trip

Because one file holds every locale, a single push imports every language. Strings marked shouldTranslate=false, and localizations with device variations or substitutions, are written back untouched while unchanged.

Translate it from the command line

Push the source-language file; strings are deduplicated against the rest of your workspace and queued for translation. Pull writes App/Localizable.xcstrings back in the same format.

npx @meterapp/glossa loginnpx @meterapp/glossa push App/Localizable.xcstrings --project appnpx @meterapp/glossa pull --project app --locale es,de,ja

Or ask an agent over MCP: “Push App/Localizable.xcstrings to Glossa and pull Spanish.” It calls push_file and pull_file. See the CLI and MCP guides.

Other formats

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