Developer uses real map data to build GTA-style game the size of Earth

A developer is using AI to build an open world game that recreates the entire planet, describing it as a mix of GTA and Apple Maps.

The project was shared on X by @_chuckyc, who explained that it runs on a custom-built engine that streams in OpenMapTiles and other public domain mapping data to render the whole Earth as a playable world.

“Ok… uh so I’m making a game… it’s like if GTA & Apple Maps v1 had a baby,” he wrote.

The Earth-sized sandbox is being built with Claude

For now, the developer says there’s no actual game yet, calling it “just a sandbox world” made up of “layers and layers of systems.”

https://twitter.com/_chuckyc/status/2110779144191537364

That includes Earth-scale weather systems with rain, storms, wind, tornadoes and hurricanes that players can watch coming from a distance. Every building also has a procedurally generated interior.

There are vehicles, skateboarding with skateparks and snowboarding with ski resorts and lifts, plus a photo mode. The engine is written in C++ with Metal and Vulkan renderers, and he says it runs on all Apple platforms except Apple Watch.

The developer revealed that much of the work is being done by AI, using Anthropic’s Claude Opus 5.5 model across three Macs in his house.

Each night before bed, he goes through everything Claude has done that day, playtests it, writes up new project plans and then sets up the next day’s work for the AI to carry out.

“The whole thing is a bit mad,” he admitted.

A rocket-powered Roadster has already been added

The developer has kept sharing updates since, including a video of what appears to be Tesla’s Roadster flying through the game using thrusters from a lunar lander he’d already built.

“Apropos of nothing, I added some of the thrusters from my lunar lander onto a sports car,” he wrote.

https://twitter.com/_chuckyc/status/2111119135354564687

The clip also marks the start of sound being added to the game, though he asked viewers to “ignore the horrible sound fx” as work on audio only began the night before.

There’s no word yet on whether the project will ever become a full game or be released to the public.