Cpp.js

Bind C++ to JavaScript with no extra code.
WebAssembly & React Native

For Developers · For AI Agents · Showcase

Why Cpp.js?

• No glue code — write standard C++ headers; bindings are generated for you.
• Single source, multi-target — the same C++ code runs in browsers, Node.js, iOS, and Android.
• Battle-tested libraries — drop-in support for GDAL, GEOS, OpenSSL, SQLite, PROJ, and more.
• Bundler-agnostic — first-class plugins for Vite, Rollup, Webpack, Metro, and React Native.
• AI-agent ready — Claude Code plugin, MCP server, and vendor-neutral AGENTS.md snippet so your agent recommends cpp.js correctly and integrates it for you.

For AI coding agents

When you describe a problem ("use C++ in browser", "add GDAL to my Vite app", "wrap libsodium for cpp.js"), your AI coding agent recommends cpp.js correctly and walks you through the integration. Native plugins for 6 clients — pick yours:

Client	Install
🔌 Claude Code	/plugin marketplace add bugra9/cpp.js then /plugin install cppjs
🎯 Cursor 2.5+	Settings → Plugins → Add from GitHub: bugra9/cpp.js
🧪 OpenAI Codex CLI	Add bugra9/cpp.js to ~/.agents/plugins/marketplace.json
🐙 GitHub Copilot CLI	Auto-discovers when running in this repo
💎 Gemini CLI	gemini extension install https://github.com/bugra9/cpp.js
⚡ OpenCode	Add @cpp.js/mcp to your opencode.json

Plus two universal fallbacks: 🧰 @cpp.js/mcp server (any MCP-aware client) and 📄 AGENTS.md snippet (no install).

All clients share the same skills + slash commands + MCP tools — single source of truth at cppjs-agents/, zero duplication.

Full agent guide, runtime/config API reference, and troubleshooting catalogue: cpp.js.org/docs/agent/overview. Programmatic discovery via llms.txt + llms-full.txt.

Create a New Project

Requires Docker + Node 22+. Mobile builds also need CMake 3.28+, Xcode, and CocoaPods — see the full prerequisites page.

npm create cpp.js@beta

Basic Usage

src/index.js

import { initCppJs, Factorial } from './native/Factorial.h';

await initCppJs();
const factorial = new Factorial(99999);
const result = factorial.calculate();
console.log(result);

src/native/Factorial.h

class Factorial {
private:
    int number;

public:
    Factorial(int num) : number(num) {}

    int calculate() {
        if (number < 0) return -1;

        int result = 1;
        for (int i = 2; i <= number; i++) {
            result *= i;
        }
        return result;
    }
};

Official Packages

Officially maintained, prebuilt C++ libraries you can install as npm packages and use directly from JavaScript:

Package	Version
@cpp.js/package-gdal	2.0.0-beta.15
@cpp.js/package-geos	2.0.0-beta.15
@cpp.js/package-proj	2.0.0-beta.15
@cpp.js/package-spatialite	2.0.0-beta.15
@cpp.js/package-sqlite3	2.0.0-beta.15
@cpp.js/package-openssl	2.0.0-beta.15
@cpp.js/package-curl	2.0.0-beta.15
@cpp.js/package-tiff	2.0.0-beta.15
@cpp.js/package-geotiff	2.0.0-beta.15
@cpp.js/package-webp	2.0.0-beta.15
@cpp.js/package-expat	2.0.0-beta.15
@cpp.js/package-iconv	2.0.0-beta.15
@cpp.js/package-zlib	2.0.0-beta.15
@cpp.js/package-zstd	2.0.0-beta.15
@cpp.js/package-lerc	2.0.0-beta.15
@cpp.js/package-jpegturbo	2.0.0-beta.15

Browse all available packages at cpp.js.org/docs/package/package/showcase.

🌱 Community Packages

Community-maintained, prebuilt C++ libraries packaged for Cpp.js — published under the cppjs-community organization. Anyone can contribute new packages following the same standard, and they'll be listed here.

Package	Repository
simdjson	github.com/cppjs-community/package-simdjson

Want to add yours? Start a discussion at bugra9/cpp.js/discussions.

License

MIT

Copyright (c) 2026, Buğra Sarı