i18n-rosetta — Translate your locale files

702

Tests

0

Dependencies

5

Script converters

35+

Language registers

⚡

One Command

Auto-detect your locale files, format, and target languages. Translate what changed. Skip what didn't.

🔀

Per-Pair Architecture

Assign different translation methods per language pair. Google Translate for French, an LLM for Japanese, a coached plugin for Plains Cree.

🎭

Custom Registers & Coaching

Steer the LLM with per-language tone instructions. Formal Sie-form for German, Taglish code-switching for Filipino, warrior's honor for Klingon.

🧱

Content Aware

Code blocks, shortcodes, interpolation variables, and raw HTML are shielded with Unicode sentinels. The LLM never sees your code.

📦

Zero Dependencies

Node.js built-ins only. No SDKs, no native modules, no build step. Works anywhere Node 20+ runs.

🔤

Conlang & Script Output

Deterministic script converters ship built-in: Cree Syllabics, Serbian Cyrillic, Klingon pIqaD, Sindarin Tengwar, Kryptonian.

Mix methods per language pair

Each source→target pair gets its own translation method, model, and quality configuration. Use what works for each language — not a one-size-fits-all.

Learn about methods →

i18n-rosetta.config.json
{
  "version": 3,
  "pairs": {
    "en:fr": {
      "method": "google-translate"
    },
    "en:ja": {
      "method": "llm",
      "model": "google/gemini-2.5-pro"
    },
    "en:crk": {
      "methodPlugin": "crk-coached-v1"
    }
  }
}

Built For

SaaS Internationalization

Translate your Next.js, Hugo, or React app to 30+ languages with per-pair quality control.

Translate 30 Languages →

Plugin Development

Build, benchmark, and distribute custom translation methods for any language pair.

Build a Plugin →

Language Preservation

Coached LLM translation for languages with no API coverage — Indigenous, endangered, constructed.

Low-Resource Guide →

Not another TMS platform

Crowdin, Phrase, and Locize are cloud platforms that require accounts, dashboards, and monthly fees. Rosetta is a CLI tool that runs in your project — no accounts, no dashboards, no vendor lock-in.

See the full comparison →