diff --git a/.changeset/fifty-ligers-refuse.md b/.changeset/fifty-ligers-refuse.md
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+---
+"@lingo.dev/_locales": patch
+---
+
+Add Sinhala (si) README translations.
diff --git a/readme/si.md b/readme/si.md
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+<p align="center">
+  <a href="https://lingo.dev">
+    <img src="https://raw.githubusercontent.com/lingodotdev/lingo.dev/main/content/banner.compiler.png" width="100%" alt="Lingo.dev" />
+  </a>
+</p>
+
+<p align="center">
+  <strong>⚡ Lingo.dev - විවෘත මූලාශ්‍ර, AI බලගැන්වූ i18n toolkit එකක් — LLMs භාවිතයෙන්ක් අත්‍යවශ්‍ය පරිවර්තන තත්ක්ෂණයකින්.</strong>
+</p>
+
+<br />
+
+<p align="center">
+  <a href="https://lingo.dev/compiler">Lingo.dev Compiler</a> •
+  <a href="https://lingo.dev/cli">Lingo.dev CLI</a> •
+  <a href="https://lingo.dev/ci">Lingo.dev CI/CD</a> •
+  <a href="https://lingo.dev/sdk">Lingo.dev SDK</a>
+</p>
+
+<p align="center">
+  <a href="https://github.com/lingodotdev/lingo.dev/actions/workflows/release.yml">
+    <img src="https://github.com/lingodotdev/lingo.dev/actions/workflows/release.yml/badge.svg" alt="Release" />
+  </a>
+  <a href="https://github.com/lingodotdev/lingo.dev/blob/main/LICENSE.md">
+    <img src="https://img.shields.io/github/license/lingodotdev/lingo.dev" alt="License" />
+  </a>
+  <a href="https://github.com/lingodotdev/lingo.dev/commits/main">
+    <img src="https://img.shields.io/github/last-commit/lingodotdev/lingo.dev" alt="Last Commit" />
+  </a>
+  <a href="https://lingo.dev/en">
+    <img src="https://img.shields.io/badge/Product%20Hunt-%231%20DevTool%20of%20the%20Month-orange?logo=producthunt&style=flat-square" alt="Product Hunt #1 DevTool of the Month" />
+  </a>
+  <a href="https://lingo.dev/en">
+    <img src="https://img.shields.io/badge/Product%20Hunt-%231%20Product%20of%20the%20Week-orange?logo=producthunt&style=flat-square" alt="Product Hunt #1 DevTool of the Week" />
+  </a>
+  <a href="https://lingo.dev/en">
+    <img src="https://img.shields.io/badge/Product%20Hunt-%232%20Product%20of%20the%20Day-orange?logo=producthunt&style=flat-square" alt="Product Hunt #2 Product of the Day" />
+  </a>
+  <a href="https://lingo.dev/en">
+    <img src="https://img.shields.io/badge/GitHub-Trending-blue?logo=github&style=flat-square" alt="Github trending" />
+  </a>
+</p>
+
+---
+
+## Compiler එකට හමු වන්න 🆕
+
+**Lingo.dev Compiler** යනු React apps multilingual කිරීම build-time දී සිදුකරන, සම්පූර්ණයෙන්ම විවෘත මූලාශ්‍ර middleware compiler එකක්.  
+React components කිසිවෙකුත් වෙනස් නොකර — ඔබේ project එක බහුභාෂාගත (multilingual) කරයි.
+
+එකවර install කරන්න:
+
+```bash
+npm install lingo.dev
+```
+
+Build config එකේ enable කරන්න:
+
+```js
+import lingoCompiler from "lingo.dev/compiler";
+
+const existingNextConfig = {};
+
+export default lingoCompiler.next({
+  sourceLocale: "en",
+  targetLocales: ["es", "fr"],
+})(existingNextConfig);
+```
+
+ඊට පසුව `next build` ක්‍රියාත්මක කරන්න — Spanish සහ French builds magically generate වෙයි ✨
+
+සම්පූර්ණ මාර්ගෝපදේශය සඳහා [docs කියවන්න →](https://lingo.dev/compiler)  
+සහ ඔබට උදව් අවශ්‍ය නම් [Discord එකට එක්වන්න](https://lingo.dev/go/discord).
+
+---
+
+### මෙය repo එක තුලදී තියෙන්නේ?
+
+| මෙවලම        | කෙටි විස්තර                                            | ලේඛන                                    |
+| ------------ | ------------------------------------------------------ | --------------------------------------- |
+| **Compiler** | Build-time React localization                          | [/compiler](https://lingo.dev/compiler) |
+| **CLI**      | Web & mobile apps සඳහා එකම command එකකින් localization | [/cli](https://lingo.dev/cli)           |
+| **CI/CD**    | Push එකකින් පසුව auto-commit + pull requests           | [/ci](https://lingo.dev/ci)             |
+| **SDK**      | Dynamic content real-time translation                  | [/sdk](https://lingo.dev/sdk)           |
+
+පහලින් tool එකකට tool එක quick summary තියෙනවා 👇
+
+---
+
+### ⚡️ Lingo.dev CLI
+
+ඔබේ terminal එකෙන්ම code & content translate කරන්න.
+
+```bash
+npx lingo.dev@latest run
+```
+
+මෙය string fingerprinting, caching, සහ incremental translation logic භාවිතා කරයි.
+
+Setup ගැන දැනගැනීමට [docs බලන්න →](https://lingo.dev/cli).
+
+---
+
+### 🔄 Lingo.dev CI/CD
+
+පරිපූර්ණ පරිවර්තන ස්වයංක්‍රීයව deploy කරන්න.
+
+```yaml
+# .github/workflows/i18n.yml
+name: Lingo.dev i18n
+on: [push]
+
+jobs:
+  i18n:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+      - uses: lingodotdev/lingo.dev@main
+        with:
+          api-key: ${{ secrets.LINGODOTDEV_API_KEY }}
+```
+
+මෙය repo එක හරිත තත්වයේ (green) තබා ගෙන product එක multilingual කරයි — කිසිදු manual step එකක් නැතුව.
+
+[Docs →](https://lingo.dev/ci)
+
+---
+
+### 🧩 Lingo.dev SDK
+
+Dynamic user content සඳහා real-time translation.
+
+```ts
+import { LingoDotDevEngine } from "lingo.dev/sdk";
+
+const lingoDotDev = new LingoDotDevEngine({
+  apiKey: "your-api-key-here",
+});
+
+const content = {
+  greeting: "Hello",
+  farewell: "Goodbye",
+  message: "Welcome to our platform",
+};
+
+const translated = await lingoDotDev.localizeObject(content, {
+  sourceLocale: "en",
+  targetLocale: "es",
+});
+```
+
+ඒක chat apps, live comments, message feeds වැනි real-time flows සඳහා සුපිරි.
+
+[Docs බලන්න →](https://lingo.dev/sdk)
+
+---
+
+## 🤝 ප්‍රජාව
+
+අපි community-driven. ඔබගේ දායකත්වය අපිට ප්‍රියයි!
+
+- අදහසක් ද? [Issue එකක් විවෘත කරන්න](https://github.com/lingodotdev/lingo.dev/issues)
+- කිසිවක් සෙමි කරන්නද? [PR එකක් යවන්න](https://github.com/lingodotdev/lingo.dev/pulls)
+- උදව් එකක් ඕනේද? [Discord එකට එන්න](https://lingo.dev/go/discord)
+
+---
+
+## ⭐ තාරා ඉතිහාසය
+
+ඔබට Lingo.dev සතුටුද? ⭐ එකක් දෙන්න!  
+අපිට 4,000 stars இலக்கு ජයගන්න උදව් කරන්න 🌟
+
+[![Star History Chart](https://api.star-history.com/svg?repos=lingodotdev/lingo.dev&type=Date)](https://www.star-history.com/#lingodotdev/lingo.dev&Date)
+
+---
+
+## 🌐 වෙනත් භාෂා පිටපත්
+
+[English](https://github.com/lingodotdev/lingo.dev) • [中文](/readme/zh-Hans.md) • [日本語](/readme/ja.md) • [한국어](/readme/ko.md) • [Español](/readme/es.md) • [Français](/readme/fr.md) • [Русский](/readme/ru.md) • [Українська](/readme/uk-UA.md) • [Deutsch](/readme/de.md) • [Italiano](/readme/it.md) • [العربية](/readme/ar.md) • [עברית](/readme/he.md) • [हिन्दी](/readme/hi.md) • [বাংলা](/readme/bn.md) • [فارسی](/readme/fa.md)
+
+ඔබේ භාෂාව නැද්ද? `i18n.json` එකට language code එක එක්කල PR එකක් යවන්න!