notnull games

• Template: cart_haxe - press "Use this template" and you have a working game.
• Docker image: ghcr.io/notnullgames/null0-cart-haxe:latest (linux/amd64 only - runs emulated on Apple Silicon)
• Your code: cart/Main.hx, compiled with haxe, HL/C + wasi-sdk
• Bindings: carts/haxe/Null0.hx (baked into the docker image for you)
• WASI is available, so ordinary file and stdio calls work.
• See carts made with Haxe
• API docs for Haxe

building

You do not install haxe, HL/C + wasi-sdk - the docker image has it, and the current null0 bindings, baked in. There is nothing in your project to keep in sync with the engine.

docker run --rm --user $(id -u):$(id -g) --platform linux/amd64 \
  -v ./cart:/src -v ./webroot:/out \
  ghcr.io/notnullgames/null0-cart-haxe:latest mygame

The template wraps that in npm start, which also serves the result and rebuilds when you save.

Haxe notes

• Callbacks are closures you assign (Null0.onUpdate = ...), not exports.
• No try/catch: wasm exception-handling is not available in the host interpreter.

a cart, in Haxe

This is carts/haxe/simple/Main.hx in the engine repo - the same file CI builds into the cart below, so it always compiles.

class Main {
  static function main() {
    Null0.onLoad = () -> {
      Null0.clear(Null0.BLUE);
      Null0.drawCircle(100, 100, 50, Null0.RED);
      Null0.drawText(Null0.FONT_DEFAULT, "hello from Haxe", 170, 92, Null0.WHITE);
    };
  }
}

// other callbacks you can set in main():
//
//   Null0.onUpdate = () -> {}
//   Null0.onButtonDown = (button:GamepadButton, player:Int) -> {}

callbacks

A cart implements the callbacks it cares about. In Haxe they look like this:

Null0.onUpdate = () -> {}

See anatomy of a cart for the full list and what each one is passed.