nuxt

Use useFetch or useAsyncData instead of calling $fetch directly in setup. These composables fetch on the server, serialize the result into the payload, and hydrate on the client without a second request.

Nuxt 4 sets the default srcDir to app/, so Vue code like components, composables, and pages lives under app/ while server/, shared/, and nuxt.config.ts stay at the root. The ~ and @ aliases now point to app/, and ~~ or @@ point to the project root.

Define a module with defineNuxtModule from @nuxt/kit, then use utilities like addComponent, addImports, addPlugin, and addServerHandler to register runtime assets. Use createResolver(import.meta.url) for path resolution and declare moduleDependencies for other modules.

Hydration mismatches occur when server-rendered HTML differs from the client render, often from browser APIs like localStorage, random values, or time-based output in setup. Use useCookie, useState, or ClientOnly to keep server and client output consistent.

Yes, Nuxt uses Nitro as its server engine, which supports platform presets. Set the preset in nuxt.config.ts or via NITRO_PRESET, for example cloudflare-pages, vercel, or netlify, then build and deploy the generated output.

Use runtimeConfig for secrets and values overridable by environment variables, with public keys exposed to the client. Use app.config for public build-time tokens like theme settings that support hot module replacement but not env overrides.