Project Fluent

Health v2 · maintenance only

Adoption not part of the score

1674 stars · 47 forks observed · 2026-08-28

What it is AI-extracted, prompt v1, taxonomy v1, 2026-08-30, confidence not recorded

Fluent is a localization system whose FTL syntax lets translators write natural-sounding, asymmetric translations with locale-specific logic like plurals, genders, and grammatical cases. This repository hosts the specification, EBNF grammar, reference parser implementation, and documentation for the ecosystem of JS, Python, and Rust implementations.

Use cases

• localize my app into multiple languages with proper plural rules
• write translations that adapt to grammatical gender and cases
• parse FTL translation files into an AST
• define a translation file format for translators
• integrate localization into React apps
• validate Fluent syntax against a formal grammar

When to choose

• you need expressive, locale-independent translations beyond simple key-value strings
• you want a well-specified, multi-language localization format with mature implementations
• you're building localization tooling and need the reference parser or spec

When to avoid

• you only need simple key-value string replacement with no grammar logic
• you need a production runtime — use fluent.js, fluent-rs, or python-fluent instead of this reference repo
• you need machine translation or translation management workflow features

Facets

library · maturity stable

internationalization parser templating documentation web-development developer-tools apis cross-platform python rust l10n ftl translation-resources specification reference-implementation ebnf-grammar localization nodejs web-server

Member repositories

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