Blue

Blue compiles JavaScript to standalone native binaries.

Write JS, ship a single executable with native GUI windows, filesystem access, HTTP servers, and system APIs - no Electron, no Node.js at runtime.

# Install
curl -fsSL https://bluejs.dev/install.sh | bash

# Write JS
echo 'window.open("<h1>Hello from Blue</h1>", "Hello", 800, 500);' > hello.js

# Compile and run
blue -compile hello.js -o hello && ./hello

bluejs.dev - Discord

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Try it in your browser (preferred)

The fastest way to get started is the Bluejs Playground, a GitHub Codespace with everything pre-installed. No setup needed. Local installation on Linux and Windows is also available but currently experimental.

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Two modes, one binary

AOT - your JavaScript is compiled directly to C++, then to native code. No interpreter at runtime. Supports classes, closures, prototypes, destructuring, template literals, and standard library methods. Use this for native windows, filesystem, and business logic.

Island - an embedded QuickJS engine bundled alongside the AOT code. Full ES2020+, async/await, and npm packages via esbuild. Use this for HTTP servers, dynamic logic, and npm dependencies.

Both run in the same process and communicate via Blue.callAot() / Blue.callIsland().

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Install

Platform	Method
Linux	curl -fsSL https://bluejs.dev/install.sh | bash
Linux	Download .deb (x86_64)
Windows	Download .zip (x86_64) - extract and run .\install.ps1

The installer checks for dependencies and tells you exactly what to install if anything is missing.

Linux dependencies

# Required for all builds
sudo apt install build-essential pkg-config

# For native GUI windows (window.open, Blue.Window, Blue.Dialog)
sudo apt install libgtk-3-dev libwebkit2gtk-4.1-dev

# For HTTP servers and hybrid island builds
sudo apt install libuv1-dev nodejs

Windows dependencies

A C++ compiler is required. Install via winget install MinGW.MinGW or MSVC Build Tools. For native GUI windows, the WebView2 SDK is also needed.

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Quick start

# Single file - AOT compile
blue -compile hello.js -o hello && ./hello

# Full hybrid project
blue -init myapp
blue -build myapp -o myapp && ./myapp

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Examples

Example	What it shows
hello-webview	Open a native window in 15 lines
aot-math	AOT loops and number crunching
markdown-notes-demo	WebView + filesystem via blue:// bridge
http-server	Hybrid HTTP server with Blue.System
react-init-hybrid	React frontend bundled into the binary
full-api-demo	All Blue.* APIs in one app

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Native APIs

// Windows
Blue.Window.setTitle("My App");
Blue.Window.setSize(1024, 768);
Blue.Window.center();

// File dialogs
var path = Blue.Dialog.showOpenDialog("Open file", "*.txt", false);
var save = Blue.Dialog.showSaveDialog("Save as", "output.txt");

// Clipboard
Blue.Clipboard.writeText("hello");
var text = Blue.Clipboard.readText();

// Shell
var result = Blue.Process.exec("ls -la");
console.log(result.stdout);

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Documentation

Getting Started	Installation, first app, project layout
CLI Reference	All commands and flags
Configuration	blue.config.json fields
API Reference	window.open, Blue.*, Node shims, WebView bridge
Hybrid Mode	Dual-entry builds, AOT and Island communication
Strict AOT	Supported JS subset
Troubleshooting	Common errors and fixes
Benchmarks	Performance vs Node.js

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License

Blue is licensed under the PolyForm Noncommercial License 1.0.0. See LICENSE, NOTICE, and THIRD_PARTY_LICENSES.md.

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npm compatibility

The island runs embedded QuickJS, not Node.js. Pure JavaScript packages are most likely to work. Packages that rely on native addons, worker_threads, child_process, or Node.js internals may not work. Always test compatibility before shipping.

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Community

• Discord: discord.gg/P9ym64jZqZ
• Issues: github.com/bluejs-team/Bluejs/issues
• Website: bluejs.dev

This repository contains the Blue compiler source, runtime, documentation, and examples.