> ## Documentation Index
> Fetch the complete documentation index at: https://docs.nt3.io/llms.txt
> Use this file to discover all available pages before exploring further.
# Supported File Formats
> Entri supports a wide range of localization file formats.
Entri supports ten localization file formats covering web, mobile, and desktop platforms. You configure the format per file pattern in your `.nt3.yml` file.
## Format overview
| Format identifier | Extension | Platform / use case |
| ----------------- | -------------- | ----------------------------- |
| `json-flat` | `.json` | Web — simple flat key-value |
| `json-nested` | `.json` | Web — nested object structure |
| `yaml` | `.yaml` | Web / Ruby on Rails |
| `po` | `.po` | GNU gettext (Linux, web) |
| `xliff` | `.xlf` | Industry standard XLIFF 1.2 |
| `xliff2` | `.xlf` | Industry standard XLIFF 2.0 |
| `arb` | `.arb` | Flutter / Dart |
| `android-xml` | `.xml` | Android |
| `ios-strings` | `.strings` | iOS / macOS |
| `ios-stringsdict` | `.stringsdict` | iOS / macOS (plurals) |
## Format examples
Flat key-value JSON. All keys live at the root level of the object.
```json theme={null}
{
"welcome_message": "Welcome to Entri",
"button_save": "Save",
"button_cancel": "Cancel",
"error_not_found": "Page not found"
}
```
Recommended for simple projects or tools that don't support nested keys.
Nested JSON objects. Keys are grouped into sections using dot-notation paths.
```json theme={null}
{
"common": {
"save": "Save",
"cancel": "Cancel"
},
"auth": {
"login": "Log in",
"logout": "Log out",
"welcome": "Welcome, {{name}}"
},
"errors": {
"not_found": "Page not found",
"server_error": "Something went wrong"
}
}
```
YAML key-value format. Common in Ruby on Rails applications.
```yaml theme={null}
en:
common:
save: Save
cancel: Cancel
auth:
login: Log in
logout: Log out
welcome: "Welcome, %{name}"
errors:
not_found: Page not found
```
GNU gettext PO format. Widely used in open-source and Linux applications.
```po theme={null}
# Entri — French translations
msgid ""
msgstr ""
"Content-Type: text/plain; charset=UTF-8\n"
"Language: fr\n"
msgid "welcome_message"
msgstr "Bienvenue sur Entri"
msgid "button_save"
msgstr "Enregistrer"
msgid "button_cancel"
msgstr "Annuler"
```
XLIFF 1.2 — the industry-standard XML-based interchange format, compatible with most professional CAT tools.
```xml theme={null}
Welcome to Entri
Bienvenue sur Entri
Save
Enregistrer
```
Application Resource Bundle — the Flutter/Dart localization format.
```json theme={null}
{
"@@locale": "en",
"welcomeMessage": "Welcome to Entri",
"@welcomeMessage": {
"description": "Shown on the home screen"
},
"buttonSave": "Save",
"@buttonSave": {},
"itemCount": "{count, plural, one{{count} item} other{{count} items}}",
"@itemCount": {
"placeholders": {
"count": { "type": "int" }
}
}
}
```
Android string resources XML format.
```xml theme={null}
Welcome to Entri
Save
Cancel
- %d item
- %d items
```
iOS/macOS `Localizable.strings` format — simple key = "value" pairs.
```
/* Home screen greeting */
"welcome_message" = "Welcome to Entri";
/* Button labels */
"button_save" = "Save";
"button_cancel" = "Cancel";
/* Error messages */
"error_not_found" = "Page not found";
```
## Configuring formats in `.nt3.yml`
Specify the format for each file pattern using the `format` key:
```yaml theme={null}
project_id: "proj_abc123"
source_language: en
file_patterns:
- path: "src/locales/{lang}.json"
format: json-nested
```
The `{lang}` placeholder is replaced with the language code (e.g., `en`, `fr`, `de`) when reading and writing files.
## Multiple patterns
You can mix formats within the same project by listing multiple patterns:
```yaml theme={null}
project_id: "proj_abc123"
source_language: en
file_patterns:
- path: "src/locales/{lang}/app.json"
format: json-nested
- path: "src/locales/{lang}/marketing.po"
format: po
```
Each pattern maps to a separate namespace in Entri, allowing you to manage files by feature or team independently.
## Platform recommendations
| You are building... | Recommended format |
| --------------------------------- | ----------------------------------------------- |
| React / Vue / Angular app | `json-nested` or `json-flat` |
| Ruby on Rails app | `yaml` |
| Android app | `android-xml` |
| iOS / macOS app | `ios-strings` (+ `ios-stringsdict` for plurals) |
| Flutter app | `arb` |
| Working with a translation agency | `xliff` or `xliff2` |
| GNU/Linux or gettext project | `po` |