Bun

# MISSION: Scaffold "Bun" 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 **Bun**.
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## 1. PROJECT SPECIFICATIONS & BENCHMARK
- **Reference Architecture**: Bun
- **What It Does**: Bun is the JavaScript and TypeScript runtime, bundler, test runner and package manager published from this repository as a single `bun` executable — a Rust and C++ codebase built around an embedded JavaScriptCore engine, positioned as a drop-in Node.js replacement.
- **Domain & Category**: All-in-One JavaScript Runtime & Toolchain
- **Production Scale**: 1M+ MAU
- **Development Mode**: CLASSIC
- **Architectural Rationale**: Implementing the runtime, bundler, installer and test runner as one Cargo workspace around a single embedded JS engine keeps startup and cross-tool integration fast, while a dedicated *_jsc crate layer isolates the JavaScriptCore bridge from the rest of the Rust codebase.
- **Live Website Reference**: https://bun.sh
- **Source Repository**: https://github.com/oven-sh/bun
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## 2. PRODUCTION TECH STACK
- **Full Stack Array**: Rust, C++, TypeScript, JavaScriptCore, SQLite, Cargo
- **Primary Language(s)**: Rust, C++, TypeScript, C, JavaScript
- **License of the reference repo**: NOASSERTION
- **Backend & APIs**: Rust — Dominant implementation language by byte count; the Cargo workspace has dozens of crates under src/ (bundler, resolver, install, http, css, semver, js_parser).; C++ — Second-largest language; used for the JavaScriptCore integration layer and native modules, reflected in crate names like css_jsc, http_jsc, js_parser_jsc.; JavaScriptCore — Bun's embedded JS/TS engine; the README says the runtime is written in Rust and powered by JavaScriptCore, bridged via numerous *_jsc crates.; TypeScript — Bundled TS/JSX transpiler support and the packages/bun-types type declarations, published as the bun-types npm workspace package.
- **Data & persistence**: SQLite — Built-in SQLite bindings for bun:sqlite; scripts/update-sqlite-amalgamation.sh vendors the SQLite source and bench/sqlite benchmarks it.
- **Infrastructure & deploy**: Docker — dockerhub/alpine, dockerhub/debian, dockerhub/debian-slim and dockerhub/distroless directories build the official bun Docker images for different base OSes.; GitHub Actions — Workflows handle release publishing, docs-site deploys, Rust/source lints and vendored-dependency update bots (cares, highway, libarchive, zstd, and others).
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## 3. KEY ARCHITECTURAL DECISIONS (audited from https://github.com/oven-sh/bun @ b52d513)
1. **Runtime, bundler, package manager and test runner are one Cargo workspace, not separate**: Cargo.toml lists dozens of member crates (src/bundler, src/install, src/http, src/css, src/semver, src/resolver, and more) that all compile into the single bun executable, rather than being distributed as independent binaries.
2. **A dedicated *_jsc crate layer bridges Rust to the embedded JavaScriptCore engine**: Crates such as src/css_jsc, src/http_jsc, src/install_jsc, src/js_parser_jsc, src/ast_jsc, src/bundler_jsc, src/sourcemap_jsc, src/semver_jsc and src/sql_jsc exist specifically to expose their non-jsc Rust counterparts to JavaScriptCore, keeping the engine-integration surface separate from the core logic.
3. **Native C dependencies are vendored and patched in-tree, not left as system libraries**: The patches/ directory carries patches for cares, hdrhistogram, highway, libarchive, libjpeg-turbo, libuv, lshpack, lsqpack, lsquic, picohttpparser, rust-argon2, tinycc, zlib and zstd, and dedicated GitHub Actions workflows (update-cares.yml, update-highway.yml, update-zstd.yml, and others) keep each vendored copy current.
4. **Official Docker images are built per base OS, not from one shared Dockerfile**: dockerhub/ has four separate build contexts (alpine, debian, debian-slim, distroless), each producing a distinct published image rather than a single multi-stage Dockerfile with build args.
5. **CI runs primarily on Buildkite, with GitHub Actions for lighter-weight checks**: .buildkite/ci.mjs, .buildkite/bootstrap.yml and .bk.yaml configure the main Buildkite pipeline (including a bootstrap Docker image in .buildkite/Dockerfile), while .github/workflows covers release publishing, docs deploys, lint jobs and bot automation.
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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**:
   - Isolate interactive UI state to leaf components. Keep core pages lightweight and performant.
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 (SQLite): 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.