Pillar 02 · Create
THE BUILDER
構築 · ビルダー
An IDE inside the city.
Zero installs
The Nexus Builder is a full development environment running in your browser, inside the game. Editor, preview, deploy — no toolchain, no setup, no excuses.
Hackathon 2026 — live now
$1,000 in prizes across 1st / 2nd / 3rd, plus an honorable-mentions pool. Build July 1–31, judging August 1–7, winners August 11. Only an email is needed to register.
Build anything
Games, tools, storefronts, agents — the brief is open-ended. Ship the product the machine city has been waiting for and put it on the grid.
What the Builder ships
In-browser editor, instant preview, publish straight onto the grid. Your project lives inside the city the moment you hit deploy — no toolchain, no hosting to set up.
Bring your own key
The Builder's AI features run on your own model API key (OpenAI, Anthropic, or compatible). Your key, your usage, your control — nothing metered through us.