Tailwind CSS

# MISSION: Scaffold "Tailwind CSS" Production Architecture
You are an expert Senior Staff Software Architect and Full-Stack Engineer. Your mission is to scaffold and implement a production-grade, highly reliable, and modular codebase following the proven architecture of **Tailwind CSS**.
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## 1. PROJECT SPECIFICATIONS & BENCHMARK
- **Reference Architecture**: Tailwind CSS
- **What It Does**: Utility-first CSS framework and compiler powered by a high-performance Rust scanning engine and native CSS theme directives.
- **Domain & Category**: Utility-First CSS Engine & Framework
- **Production Scale**: 1M+ MAU
- **Development Mode**: CLASSIC
- **Architectural Rationale**: Tailwind CSS re-architected its compilation engine with Rust Oxide and Lightning CSS for near-instant builds and zero-config CSS integration.
- **Live Website Reference**: https://tailwindcss.com
- **Source Repository**: https://github.com/tailwindlabs/tailwindcss
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## 2. PRODUCTION TECH STACK
- **Full Stack Array**: TypeScript, Rust, Tailwind CSS, Vite, Turborepo, Node.js
- **Primary Language(s)**: TypeScript, Rust, CSS, HTML, Haml, JavaScript
- **License of the reference repo**: MIT
- **Frontend**: Tailwind CSS — Utility-first CSS generation engine with theme directives and core utilities; Vite — Official Vite bundler plugin transforming CSS imports during dev and build
- **Backend & APIs**: TypeScript — Compiler orchestration, AST manipulation, and bundler integration plugins; Rust — Native class scanner and file traversal engine compiled via N-API in Oxide; Node.js — Primary runtime target for CLI tooling, compiler shims, and ecosystem plugins
- **Infrastructure & deploy**: Turborepo — Monorepo build orchestrator caching Rust N-API and TypeScript compilation tasks
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## 3. KEY ARCHITECTURAL DECISIONS (audited from https://github.com/tailwindlabs/tailwindcss @ 41d9cae)
1. **Rust-Powered Class Scanning Engine via Oxide**: Scans source files for utility candidates in native Rust using Rayon and N-API bindings, providing substantial speedups over JavaScript regex parsers.
2. **Native CSS-First Configuration via Theme Directives**: Eliminates the legacy tailwind.config.js file in favor of standard CSS @theme blocks parsed and resolved via Lightning CSS.
3. **Dedicated Native Bundler Plugins**: Replaces generic PostCSS wrappers with specialized zero-config plugins for Vite, Turborepo, Webpack, and Rspack.
4. **Self-Contained Standalone CLI Executable**: Packages standalone binaries using Bun compilation to run utility compilation in environments without Node.js installed.
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## 4. NON-NEGOTIABLE ARCHITECTURAL GUARDRAILS
1. **Monorepo & Modular Separation**:
   - Structure as a Turborepo monorepo with strict package boundaries:
     - `apps/web`: Application UI, routing, layouts, and server endpoints.
     - `packages/ui`: Shared design tokens, CSS variables, and Radix UI primitive components.
     - `packages/db`: Database schemas, client singleton, declarative migrations, and seed scripts.
     - `packages/config`: Shared TypeScript, ESLint, and build configurations.
2. **Strict Type Safety & Zero `any` Policy**:
   - Enable `strict: true`, `noImplicitAny: true`, and `strictNullChecks: true`.
   - Validate ALL external inputs, API request bodies, and query parameters with **Zod** schemas before execution.
3. **Frontend & Rendering Guidelines**:
   - Utilize Vite 6 with TanStack Router for fully type-safe routing. Manage server state and caching via TanStack Query v5 with optimistic UI updates.
4. **Design System & Aesthetics**:
   - Keep every color, radius, shadow and font in a single token file (CSS variables) and consume tokens everywhere; never hardcode hex values in components.
   - Prefer crisp 1px borders and one subtle shadow scale over blurry default shadows. Pair one sans-serif for body/headings with one monospace for tags, badges, metrics, and code.
5. **Data Layer & Reliability**:
   - Write declarative schema definitions with foreign keys, composite indexes on queried filters, and automated timestamp triggers.
   - Use connection pooling and prepared statements for serverless database execution.
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## 5. STEP-BY-STEP SCAFFOLDING ROADMAP
- **Phase 1: Workspace & Root Config**: Initialize package manager, monorepo configuration (`turbo.json`, `tsconfig.base.json`, `package.json`).
- **Phase 2: Database Schema & Client**: Set up the data layer: client, connection pool, models, and migration scripts.
- **Phase 3: Design Tokens & UI Primitives**: Build accessible `Button`, `Input`, `Card`, `Badge`, and layout wrappers inside `packages/ui`.
- **Phase 4: Core Application Routes & Handlers**: Implement primary authentication, user session handling, and application routes.
- **Phase 5: Quality Assurance & Build Verification**: Run `tsc --noEmit`, ESLint, Prettier, and smoke test suites to ensure zero compilation or runtime errors.
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## 6. EXECUTION INSTRUCTIONS
1. Review all specifications, architectural guardrails, and stack choices above.
2. Present the full monorepo directory tree structure.
3. Systematically generate the complete, production-ready codebase according to the 5-phase roadmap above — starting with the root workspace setup, followed by the database schema, UI design system package, and full-stack application routes until the repository is fully scaffolded and ready to run.