Native runtime for Three.js games. Write Three.js, ship to Steam as a small native binary. Same codebase runs in browser.

No Electron. No Chromium. No bullshit.

three-native is a Zig-based runtime that hosts an unmodified Three.js build on top of a lightweight JavaScript engine and a browser API shim. The goal is to make Three.js apps run natively with minimal footprint while keeping the existing Three.js codebase intact.

┌─────────────────────────────────┐
│  Your Game (Three.js)           │  ← Unmodified Three.js code
├─────────────────────────────────┤
│  Three.js (submodule)           │
├─────────────────────────────────┤
│  Browser Shim                   │  ← WebGL, DOM, etc.
├─────────────────────────────────┤
│  mquickjs                       │  ← 100KB JS engine
├─────────────────────────────────┤
│  Native Backend (Zig)           │  ← sokol or wgpu-native
└─────────────────────────────────┘

• 10KB RAM, 100KB ROM
• ES5 subset encourages clean code
• JS is not the hot path; GPU calls are
• Can swap to V8/JSC later if needed

Three.js touches these browser APIs:

• WebGL: WebGLRenderingContext / WebGL2RenderingContext
• Canvas: HTMLCanvasElement, getContext, width/height
• Timing: requestAnimationFrame, performance.now()
• Assets: Image, createImageBitmap, fetch, FileReader, URL.*
• Input: addEventListener, pointer lock, gamepad API
• Audio (phase 2): AudioContext, AudioBuffer, GainNode, etc.
• Misc: document.createElement('canvas'), TextDecoder, console.*

git clone --recursive https://github.com/mattneel/three-native
cd three-native
zig build run -- examples/creating-a-scene.js

Requires:

• Zig 0.15.2+
• Node.js + npm (used to build the ES5 Three.js bundle on first run)

Notes:

• zig build run automatically runs npm install and builds examples/three.es5.js.
• You can rebuild the bundle manually with zig build three-es5.
• Three.js is a submodule, so --recursive is required on clone.

• deps/sokol-zig is vendored to keep Sokol patches reproducible. We raise SG_MAX_UNIFORMBLOCK_MEMBERS to 64 to match current Three.js shader needs.

Early stage. Milestones are tracked in KICKSTART.md.

When running Three.js examples, you may see Sokol warnings like:

GL_UNIFORMBLOCK_NAME_NOT_FOUND_IN_SHADER: uniform block name not found in shader
GL_VERTEX_ATTRIBUTE_NOT_FOUND_IN_SHADER: vertex attribute not found in shader

These are benign. They occur because:

1. Three.js shaders declare many standard uniforms/attributes for optional features
2. The GLSL compiler optimizes out unused ones
3. Sokol logs a warning when glGetUniformLocation/glGetAttribLocation returns -1

The runtime uses preprocessor-aware filtering to minimize these, but the GLSL compiler's dead code elimination is more aggressive than our heuristics. Unused uniforms simply won't be applied, which is correct behavior.

• Design docs (GitHub Pages): https://mattneel.github.io/three-native/docs/design/
• Local mdbook source: docs/design

If you want to help:

1. Pick an unimplemented gl.* function
2. Implement it in src/shim/webgl.zig
3. Add a test
4. Open a PR

Issues and ideas are welcome.

If this saved you from having to wrangle Electron, please consider sponsoring. Every little bit helps.

MIT