# I18n Localization

> Internationalization and localization patterns. Detecting hardcoded strings, managing translations, locale files, RTL support.

- **Type:** Skill
- **Install:** `agentstack add skill-matthewbspeicher-remembr-dev-i18n-localization`
- **Verified:** Yes — security-reviewed for prompt injection and unsafe behavior
- **Seller:** [matthewbspeicher](https://agentstack.voostack.com/s/matthewbspeicher)
- **Installs:** 0
- **Category:** [Agent Skills](https://agentstack.voostack.com/c/agent-skills)
- **Latest version:** 0.1.0
- **License:** MIT
- **Upstream author:** [matthewbspeicher](https://github.com/matthewbspeicher)
- **Source:** https://github.com/matthewbspeicher/remembr-dev/tree/main/.agent/skills/i18n-localization

## Install

```sh
agentstack add skill-matthewbspeicher-remembr-dev-i18n-localization
```

Requires the [AgentStack CLI](https://agentstack.voostack.com/docs/cli). Works with Claude Code, Cursor, and any MCP-compatible agent.

## About

# i18n & Localization

> Internationalization (i18n) and Localization (L10n) best practices.

---

## 1. Core Concepts

| Term | Meaning |
|------|---------|
| **i18n** | Internationalization - making app translatable |
| **L10n** | Localization - actual translations |
| **Locale** | Language + Region (en-US, tr-TR) |
| **RTL** | Right-to-left languages (Arabic, Hebrew) |

---

## 2. When to Use i18n

| Project Type | i18n Needed? |
|--------------|--------------|
| Public web app | ✅ Yes |
| SaaS product | ✅ Yes |
| Internal tool | ⚠️ Maybe |
| Single-region app | ⚠️ Consider future |
| Personal project | ❌ Optional |

---

## 3. Implementation Patterns

### React (react-i18next)

```tsx
import { useTranslation } from 'react-i18next';

function Welcome() {
  const { t } = useTranslation();
  return {t('welcome.title')};
}
```

### Next.js (next-intl)

```tsx
import { useTranslations } from 'next-intl';

export default function Page() {
  const t = useTranslations('Home');
  return {t('title')};
}
```

### Python (gettext)

```python
from gettext import gettext as _

print(_("Welcome to our app"))
```

---

## 4. File Structure

```
locales/
├── en/
│   ├── common.json
│   ├── auth.json
│   └── errors.json
├── tr/
│   ├── common.json
│   ├── auth.json
│   └── errors.json
└── ar/          # RTL
    └── ...
```

---

## 5. Best Practices

### DO ✅

- Use translation keys, not raw text
- Namespace translations by feature
- Support pluralization
- Handle date/number formats per locale
- Plan for RTL from the start
- Use ICU message format for complex strings

### DON'T ❌

- Hardcode strings in components
- Concatenate translated strings
- Assume text length (German is 30% longer)
- Forget about RTL layout
- Mix languages in same file

---

## 6. Common Issues

| Issue | Solution |
|-------|----------|
| Missing translation | Fallback to default language |
| Hardcoded strings | Use linter/checker script |
| Date format | Use Intl.DateTimeFormat |
| Number format | Use Intl.NumberFormat |
| Pluralization | Use ICU message format |

---

## 7. RTL Support

```css
/* CSS Logical Properties */
.container {
  margin-inline-start: 1rem;  /* Not margin-left */
  padding-inline-end: 1rem;   /* Not padding-right */
}

[dir="rtl"] .icon {
  transform: scaleX(-1);
}
```

---

## 8. Checklist

Before shipping:

- [ ] All user-facing strings use translation keys
- [ ] Locale files exist for all supported languages
- [ ] Date/number formatting uses Intl API
- [ ] RTL layout tested (if applicable)
- [ ] Fallback language configured
- [ ] No hardcoded strings in components

---

## Script

| Script | Purpose | Command |
|--------|---------|---------|
| `scripts/i18n_checker.py` | Detect hardcoded strings & missing translations | `python scripts/i18n_checker.py ` |

## Source & license

This open-source skill is cataloged on AgentStack and links to its original source — we do not rehost the code.

- **Author:** [matthewbspeicher](https://github.com/matthewbspeicher)
- **Source:** [matthewbspeicher/remembr-dev](https://github.com/matthewbspeicher/remembr-dev)
- **License:** MIT

Install and usage instructions live in the source repository linked above.

## Pricing

- **Free** — Free


## Versions

- **0.1.0** — security scan: passed — Imported from the upstream source.

## Links

- Listing page: https://agentstack.voostack.com/l/skill-matthewbspeicher-remembr-dev-i18n-localization
- Seller: https://agentstack.voostack.com/s/matthewbspeicher
- Browse the marketplace: https://agentstack.voostack.com/browse

---
Listed on AgentStack — the marketplace for AI agent skills and MCP servers. Every listing is security-reviewed. Creators keep 70%.