Meet Gemma

My daughter Gemma is five. She built a 3D game called Smoosh Patrol.

She didn't write a line of JavaScript, HTML, or CSS. She talked to the Antigravity agent and told it what she wanted: what the world should look like, speed boosts, flying into space, how the game should play.

She had strong opinions about physics. The car had to go higher in space. It had to feel lighter on the Moon. When it didn't feel right, she said so, and the agent changed it.

The Pace of a Five-Year-Old

Her sessions were a nonstop stream of ideas. New physics. New colors. Animal shapes. Each one spoken out loud, built, tested, and replaced by the next.

She Took My Laptop

Antigravity ran in the IDE on my laptop. So every idea Gemma had needed my laptop.

She had a lot of ideas. I was locked out of my own computer.

Put Gemini in the Game

So we asked a simple question.

Instead of building through my IDE, Gemma would talk to the game itself. The loop moved off my laptop and into the running game, through a voice HUD on screen. She got her own tool. I got my laptop back.

Voice to Code to Scene

Three steps, all in the browser.

A small Go proxy sits between the game and the API. It handles the requests, cleans up the payload, and rate-limits so a five-year-old can't run up the bill.

Here's what Gemini wrote when she said "Turn the car into a tiger."

// 1. Clear original cop car meshes
while (window.carGroup.children.length > 0) {
  window.carGroup.remove(window.carGroup.children[0]);
}

// 2. Build tiger body
const body = new THREE.Mesh(
  new THREE.BoxGeometry(1.6, 1.0, 3.2),
  new THREE.MeshStandardMaterial({ color: 0xffaa00 })
);
window.carGroup.add(body);

// 3. Add stripes on the back
for (let i = -1; i <= 1; i++) {
  const stripe = new THREE.Mesh(...);
  window.carGroup.add(stripe);
}

Running generated code with eval() is fine for a sandbox toy in your own browser. Don't ship it to production.

Making Things Happen

Changing shapes wasn't enough. Gemma wanted things to happen. So we let Gemini hook into the render loop.

window.customTicks is a global array of functions that run every frame. Generated code can push into it to animate things, check distances, and react.

Proximity checks fire when the player gets close to something. Canvas textures draw signs, like a "CAR WASH" billboard, onto a 2D canvas and wrap them onto 3D meshes.

Put together, one spoken idea becomes a working car wash: drive within range, water sprays, and the tiger turns back into a police car.

Anyone With a Voice

A five-year-old programmed a 3D game by talking. The barrier to building software is gone.

For those of us who build software for a living, the work moves. Less typing boilerplate. More reviewing what agents wrote and deciding where the boundaries go, like the proxy and the sandbox here.