I built a cycling game by talking to Claude, and you can ride it

I ride indoors a lot, and I’ve always wished the games looked better. So this week I asked Claude Fable 5.2 a simple question: how would I make a cycling game that looks amazing?

Two days later I have one. This is the Alps course, in the mist:

It isn’t a mock-up. You can ride it in your browser right now.

Fable 5.2 and Spacefast are an incredible combination

I didn’t write a line of code. I described what I wanted, Fable built it, and I told it what I thought. When it was ready, Spacefast put it on the internet. That’s the whole process.

What surprised me is how far that goes. A year ago this would have been a rough demo. Now it’s a single web page with real light, weather, wind in the grass and a road I’d happily ride for an hour.

How we built it

We started with a short proof of concept: a road, some hills and a low evening sun. Then I kept asking for more.

• One sun lights everything. The sky colour, the distant haze and the reflections on the road all come from that one light, so the scene sits together.
• It behaves like a camera. Soft glow, sun shafts, a touch of speed blur, film grain and darkened corners.
• Photographed surfaces. The road, grass and rock use free textures from Poly Haven, with road wear and markings painted on top.
• Grass everywhere. It covers the verges and the hillsides, and it moves in the wind.
• Weather. Golden evening, overcast, rain and mist. Rain wets the road and puts drops on the lens.

Then I asked for my own loop. Fable took a route around Leckhampton Hill, pulled the Environment Agency’s open laser-scan height data, and built the real climb. Every rise is where it is in real life.

It’s playable

Plenty of AI demos are a nice video and nothing else. This one you ride.

• Set your power with the slider or the up and down keys.
• Change the weather with the buttons, or turn on Voice and say “rain”.
• Skip ahead with the right arrow key.
• There’s a button to connect a Bluetooth smart trainer. I haven’t tested that on my own trainer yet, so treat it as experimental.

I call the voice control “God mode”. You’re pedalling along in the evening sun, you say “rain”, and the sky closes in and the road goes wet. Say “mist” and the hills disappear. It never gets old.

Two courses are live: the Alps and my Leckhampton loop. It works best on a laptop or desktop.

You have to be discerning

Fable did the building, but the look came from me saying no. A lot.

• The handlebars rocked about as you pedalled. Realistic, and really distracting. I had them held still.
• The first hillside grass made everything look worse, like a dark carpet. We went round that one a few times.
• In the rain, the hills came out paler than the sky. It looked wrong, so we fixed the light.
• On the Leckhampton loop, Fable added every real building from the map. They were horrible. So I had a different idea: take the hill back to the 19th century. No modern houses, just sheep on the hill, hay stooks in the fields and smoke from the quarry.
• We built a painted night mode too. I didn’t love it, so it’s off the live site until it’s right.

None of that needed technical skill. It needed an eye, and the patience to keep saying “not quite”. I think that’s the real job now.

Spacefast made getting online easy

Getting something like this onto the internet used to be its own little project. Hosting, domains, uploads, the lot.

With Spacefast I said “host this on Spacefast”, and a few seconds later I had a link to share. Every change since has been one command, and each one is saved as a new version.

How I’d make money from it (I’m not going to)

I built this for fun and I’m leaving it there. But if I wanted to turn it into a business, I’d keep the ride free and sell add-on packs.

• Course packs. The great climbs, a coast road, a city at dawn.
• Your own loop. Send your local route and get it back built from real height data, like my Leckhampton one.
• Time-travel packs. The same roads in another century.
• Look packs. Snow, autumn, night, or painted like a Van Gogh.

The point is that each pack would now be days of work, where it used to be months.

Have a ride

Ride the Alps, or climb Leckhampton Hill, and tell me what you think. I’d love to know which weather you end up riding in.