UI Rules

UI Rules started with a familiar frustration: teams spend years refining design systems, then AI coding tools build screens that follow none of it. Pasting guidelines into prompts doesn't scale, and instruction files drift out of date the moment the system changes. So we built one place where rules and styles live together, served live to every connected tool. It grew out of building shadcncraft, a design system for Figma and React, where the gap between documented decisions and AI-generated output was impossible to ignore. UI Rules is built in Melbourne, Australia, and is free to start.

A TypeScript Turborepo monorepo, pnpm and Node 20 throughout. The web app is Next.js with shadcn/ui and Tailwind CSS, deployed on Vercel. The API is NestJS with PostgreSQL, publishing an OpenAPI contract that generates our typed client. Rules and styles are served to AI tools by our MCP server, with a CLI riding the same OAuth flow, and the in-app agent runs as its own service. Backend, MCP, and agent ship as Docker containers on Railway. The Figma plugin syncs variable collections into your brand, and the curated ruleset is authored in Notion and compiled into the product.