antfu/nitro

> The skill is based on Nitro v3 (beta), generated at 2026-06-22.

Nitro is a framework-agnostic, deployment-agnostic server toolkit powered by H3 v2, unstorage, and Vite/Rolldown/Rollup. It powers Nuxt and works standalone. From one codebase it builds optimized output for Node.js, Bun, Deno, Cloudflare, Vercel, Netlify, and more.

Key capabilities:

• Filesystem routing with H3 v2 event handlers, dynamic params, and method suffixes.
• Route rules for declarative caching, headers, redirects, proxying, and auth.
• Caching layer (cached handlers/functions, SWR) on top of unstorage KV.
• Runtime config overridable via NITRO_* env vars.
• Tasks (on-demand + scheduled/cron), WebSockets/SSE, a SQL database layer, and OpenAPI auto-docs.
• Plugins & lifecycle hooks, custom renderer/server entry, and portable deployment presets.

> Nitro v3 renamed the package nitropack → nitro and adopts H3 v2 (web-standard Request/Response). If unsure about v2-vs-v3 APIs, read advanced-migration first.

Core

| Topic | Description | Reference | |-------|-------------|-----------| | Routing | File-based routes, defineHandler, params, middleware, route rules, errors | core-routing | | Configuration | nitro.config.ts, defineConfig, key options, runtime config | core-configuration | | Storage | unstorage KV, mount points, drivers, dynamic mounts | core-storage | | Cache | defineCachedHandler, defineCachedFunction, SWR, invalidation | core-cache | | Assets | Public assets, compression, server assets via storage | core-assets | | Rendering | Renderer (HTML/SSR), server entry, framework integration | core-rendering |

Features

| Topic | Description | Reference | |-------|-------------|-----------| | Plugins & Hooks | definePlugin, runtime lifecycle hooks, error capture | features-plugins | | Tasks | On-demand & scheduled (cron) tasks, runTask | features-tasks | | WebSocket & SSE | defineWebSocketHandler, pub/sub, namespaces, event streams | features-websocket | | Database | Built-in SQL layer via db0, useDatabase, connectors | features-database | | OpenAPI | Auto spec from defineRouteMeta, Scalar/Swagger UIs | features-openapi |

Advanced / Deployment

| Topic | Description | Reference | |-------|-------------|-----------| | Deployment Presets | Runtimes & providers, compatibility dates, platform integration | deploy-presets | | v2 → v3 Migration | Package rename, nitro/* imports, H3 v2 API, preset changes | advanced-migration |