Nuxt is a production-grade, open-source meta-framework for building full-stack web applications with Vue.js. It provides a comprehensive developer experience with file-based routing, server-side rendering (SSR), static site generation (SSG), incremental static regeneration (ISR), and a powerful module ecosystem. The repository is a monorepo containing the core framework (`@nuxt/nuxt`), a toolkit for module authors (`@nuxt/kit`), configuration schema (`@nuxt/schema`), and multiple builder integrations (Vite, Webpack, Rspack) plus a Nitro-based server engine (`@nuxt/nitro-server`). Architecturally, Nuxt operates in two phases: build-time and runtime. At build time, it loads configuration, installs modules, scans components and pages, generates optimized code (auto-imports, route definitions, plugin arrays), and bundles the application using the configured builder. At runtime, it handles SSR/CSR rendering, data fetching via `useFetch`/`useAsyncData`, state management with `useState`, routing with vue-router, and server-side logic via Nitro. The framework is highly extensible through hooks, modules, and layers, allowing customization at every level. Key entry points include `createNuxt`, `loadNuxt`, and `build` from `@nuxt/kit`, the CLI (`nuxi`), and runtime composables like `useFetch`, `useAsyncData`, `useHead`, and `useRouter`. External dependencies include Vue 3, Vite/Webpack/Rspack, Nitro, unhead, ufo, devalue, and many others. The codebase is actively maintained with a large test suite (unit, integration, e2e) and a sophisticated diagnostics system for developer feedback.