create the ultimate brutalist city builder. you should have lots of controls over buildings in ways that are delightful and inuitive to people who just want to play, but are sophisticated and deep for people who know something about architecture. you should be able to play a lot with design and approach. there should be simulation modes and different ways to view or experience the city. make it stunning.
Make it yours. Swap "brutalist city builder" for another style or kind of builder, and keep the two audiences in "delightful and inuitive to people who just want to play, but are sophisticated and deep for people who know something about architecture". The last sentence ("there should be simulation modes and different ways to view or experience the city") is what produced the sun, wind, and drawing modes.
Brutalist city builder in raw concrete
BRUT, a city builder in raw concrete: twelve parametric building types you pull about by hand or tune in an inspector, with studies of sun, wind, weather, and age. Claude Fable 5.1 made it in a single shot from a five-sentence prompt.
“I am quite impressed with how pretty the results are.”
- Claude Fable 5.1
- Three.js
- One-shot
How it was made
The creator says Fable 5.1 made it "in a single shot from a prompt", and posts it a little over a year after his GPT-5 version (quoted in the post), which came from a one-line prompt plus "make it better" a bunch. The repo vendors Three.js r180 and needs no build step. The prompt keeps the creator's typo "inuitive".
Claude Fable 5.1 · Three.js
Source and credit
X · Oct 4, 2026 · 252 likes · 43k views · 72 comments
Authorship not stated by the source
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Look notesby Reference
A city builder of raw-concrete slab blocks, towers, and terraced estates on green hills, with an inspector panel on the right and a timeline along the bottom.
- Color
- Raw grey concrete, grass greens, and a pale hazy sky, with a few red and ochre facade panels and red accents in the interface.
- Type
- Small sans-serif interface labels in the top bar and the right-hand inspector, with the estate name EASTFIELD in the top left.
- Framing
- Wide 2.55:1 frames. The first shots are eye-level views across a plaza with a V-shaped concrete sculpture toward slab blocks and towers; later shots are high oblique aerials of the estate.
- Structure
- Eye-level views of the plaza and slab blocks, a tower selected in the inspector, a long low block, then aerials of the estate with info panels open, a red-and-ochre building added, a domed structure, and a final pull-out to the whole city among patchwork fields.
