Introduction

Why Flame Exists

Building documentation sites often means wrestling with heavyweight frameworks, slow tooling, and complex configuration. Flame takes a different approach: minimal, runtime-agnostic, and React-first. It is designed to let you focus on writing content while providing a fast, developer-friendly foundation — whether you use Bun, Node.js, or Deno.

Overview

Flame is a lightweight runtime for building documentation websites using React, MDX, and filesystem-based routing. The toolchain runs on Bun, Node.js, or Deno — the final output is pure static HTML.

• React-first — JSX/TSX, hooks, component composition
• MDX content — write Markdown with embedded React components
• Filesystem routing — auto-discover pages from docs/ folder
• Lightweight SSR — server-side rendering without a heavy framework
• Client hydration — interactive islands for sidebar, TOC, and MDX components
• HMR — instant reload on content changes during development
• Static build — pre-render all pages to static HTML for deployment
• Built-in search — full-text search index generated at build time
• Plugin system — extend the build pipeline and dev server with hooks
• Config-driven themes — switch presets or use custom colors via docu.json
• Runtime-agnostic — the same CLI, the same output, on Bun, Node.js, or Deno

Technology Stack

• Runtime — Bun, Node.js >= 20.11, or Deno >= 2.x (auto-detected)
• React 19 + React DOM — rendering (SSR + client hydration)
• @docubook/core — MDX compilation, rehype/remark plugins
• @docubook/runt — runtime adapters (Bun.serve, Node HTTP, Deno HTTP)
• @docubook/ui-react — reusable UI components (sidebar, TOC, navbar)
• @docubook/themes-colors — config-driven color system
• Tailwind CSS v4 + daisyUI v5 — styling
• Lucide React — icons

Architecture

The runtime is only needed for the build toolchain and local dev server:

graph TD
    MDX["MDX (.mdx)"]
    CORE["@docubook/core<br/><small>compile pipeline</small>"]
    FLAME["@docubook/flame<br/><small>SSR + hydration + plugins</small>"]
    BUN["Bun<br/><small>Bun.serve + native TS</small>"]
    NODE["Node.js<br/><small>Node HTTP + esbuild</small>"]
    DENO["Deno<br/><small>Deno HTTP + esbuild</small>"]
    STATIC["Static HTML<br/><small>deploy to any CDN or static host</small>"]

    MDX --> CORE
    CORE --> FLAME
    FLAME --> BUN
    FLAME --> NODE
    FLAME --> DENO
    BUN --> STATIC
    NODE --> STATIC
    DENO --> STATIC

Build vs Dev Server