formatjs

# FormatJS

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This repository is the home of [FormatJS](http://formatjs.github.io/) and related libraries.

**Slack:** Join us on Slack at [formatjs.slack.com](https://formatjs.slack.com/) for help, general conversation and more 💬🎊🎉
You can sign-up using this [invitation link](https://join.slack.com/t/formatjs/shared_invite/enQtNjYwMzE4NjM1MDQzLTA5NDE1Y2Y1ZWNiZWI1YTU5MGUxY2M0YjA4NWNhMmU3YTRjZmQ3MTE3NzJmOTAxMWRmYWE1ZTdkMmYzNzA5Y2M).

## Development

See [CONTRIBUTING.md](CONTRIBUTING.md#Development) for instructions.

## Published Packages

Choose by application ecosystem. Registry names identify how to install a package;
implementation language can differ. For example, `@formatjs/cli` is Rust-backed
and distributed through npm.

| Ecosystem               | Distribution    | Entry point                                                         |
| ----------------------- | --------------- | ------------------------------------------------------------------- |
| JavaScript / TypeScript | npm             | React, Vue, Svelte, message formatting, Intl polyfills, build tools |
| Rust                    | crates.io       | Message runtime, parsers, Intl cores                                |
| Python                  | PyPI            | Rust-backed message runtime and parser bindings                     |
| Hermes / React Native   | GitHub Releases | Native SDK with Rust libraries and C++/JSI installers               |

### Intl APIs: npm and Rust

npm packages expose JavaScript APIs with TypeScript types. Rust crates expose
native operations for Rust applications and host integrations. LocaleMatcher is a
proposal ponyfill; the other rows implement standardized Intl APIs.

| API                 | JavaScript / TypeScript (npm)                                                                            | Rust (crates.io)                                                                                  |
| ------------------- | -------------------------------------------------------------------------------------------------------- | ------------------------------------------------------------------------------------------------- |
| Collator            | [`@formatjs/intl-collator`](https://www.npmjs.com/package/@formatjs/intl-collator)                       | [`formatjs_intl_collator`](https://crates.io/crates/formatjs_intl_collator)                       |
| DateTimeFormat      | [`@formatjs/intl-datetimeformat`](https://www.np