aws-amplify

AWS Amplify Gen2

Build and deploy full-stack applications using AWS Amplify Gen2's TypeScript code-first approach. This skill covers backend resource creation, frontend integration across 8 frameworks, and deployment workflows.

Prerequisites

• Node.js ^18.19.0 || ^20.6.0 || >=22 and npm
• AWS credentials configured (aws sts get-caller-identity succeeds)
• For sandbox: npx ampx --version returns a valid version
• For mobile: Platform-specific tooling (Xcode, Android Studio, Flutter SDK)

Defaults & Assumptions

When the user does not specify a framework:

• Web: Default to React (Vite) and explain the choice.
• Mobile: Ask which platform (Flutter, Swift, Android, or React Native) — there is no universal mobile default, so guessing leads to wasted effort.
• Neither specified: If the user says "build an app" without clarifying web vs. mobile, ask before proceeding — the framework choice affects every subsequent step.
• Backend only: If only backend changes are requested and no frontend framework is mentioned, skip the frontend integration step entirely.

When the user does not specify tooling or strategy:

• Package manager: Default to npm unless the user specifies yarn or pnpm.
• Language: Default to TypeScript. Gen2 backends are TypeScript-only; frontends should follow the project's existing language.
• Next.js: Default to App Router unless the user specifies Pages Router.
• React Native: Ask whether the user uses Expo or bare React Native CLI.
• Auth: You MUST ask which login method the user wants (email/password, social login, SAML, passwordless, etc.). Do not assume a default.
• Data authorization: default to publicApiKey (allow.publicApiKey()) — this is the starter template default. When auth is added, switch to owner-based (allow.owner()) with defaultAuthorizationMode: 'userPool'.

Quick Start — Route to the Right Reference

Step 1: Identify the Task Type

Step 2: Backend Features

Read the corresponding reference for each backend feature you need:

Each backend feature file is self-contained. Load only what you need.

Routing note: These files apply for both adding and modifying features. Route to the same file whether the user says "add auth" or "change auth config" — each reference covers the full define surface.

Step 3: Frontend Integration

After configuring backend resources, connect the frontend. Choose by platform and feature:

Web (React, Next.js, Vue, Angular, React Native):

Mobile (Flutter, Swift, Android):

Note: AI and Functions frontend patterns are included in ai.md and functions-and-api.md respectively — they are not split into separate web/mobile files.

Core Concepts

Amplify Gen2 Architecture

• Code-first: All backend resources defined in TypeScript under amplify/
• Main config: amplify/backend.ts imports and combines all resources via defineBackend()
• Resource files: amplify/auth/resource.ts, amplify/data/resource.ts, amplify/storage/resource.ts, amplify/functions/<name>/resource.ts
• Generated output: amplify_outputs.json — consumed by frontend Amplify.configure(). Gitignored — generated by npx ampx sandbox (local dev) or npx ampx pipeline-deploy (CI/CD), never committed.

Directory Structure

amplify/ and src/ must be siblings under the project root — placing them at different directory levels breaks sandbox detection. (Exception: in monorepos, amplify/ may be in a packages/ subdirectory — the key is that amplify_outputs.json must be accessible from the frontend entry point.)

project-root/
├── amplify/
│   ├── backend.ts            # defineBackend({ auth, data, ... })
│   ├── auth/resource.ts      # defineAuth({ ... })
│   ├── data/resource.ts      # defineData({ schema })
│   ├── storage/resource.ts   # defineStorage({ ... })
│   └── functions/
│       └── my-func/
│           ├── resource.ts   # defineFunction({ ... })
│           └── handler.ts    # export const handler = ...
├── src/                      # Frontend code
├── amplify_outputs.json      # Generated, gitignored — never edit or commit
└── package.json

Key APIs

Framework Setup

These patterns apply to every web task — not just new projects. Verify each one before implementing any feature.

Gen2 Detection

Before modifying any code, check if the project is already Gen2:

1. amplify/ directory exists with backend.ts
2. @aws-amplify/backend in package.json devDependencies

If both are true, the project is already Gen2 — skip to feature implementation. If amplify/.config/ exists instead, this is a Gen1 project — do not proceed (requires separate migration skill).

Frontend Configuration

Import the generated outputs and configure Amplify in the correct entry point for your framework. Placing this in the wrong file causes silent failures — Amplify API calls return undefined or empty responses with no error.

WARNING: amplify_outputs.json must exist before the app can compile — without it, the build fails with a module-not-found error. Run npx ampx sandbox (or npx ampx sandbox --once) first to generate it. See scaffolding.md for the correct sequence.

React (Vite) — src/main.tsx:

import { Amplify } from 'aws-amplify';
import outputs from '../amplify_outputs.json';
Amplify.configure(outputs);

Next.js (App Router) — app/layout.tsx:

Important: layout.tsx is a server component in App Router. Use the ConfigureAmplifyClientSide client component pattern below instead.

{ ssr: true } is a Next.js-only option (not needed by Vue, Angular, or React SPA). Both App Router and Pages Router use it, but apply it differently:

• App Router — set globally in ConfigureAmplifyClientSide client component
• Pages Router — set per-file where server-side access is needed

Next.js App Router: Client-Side Configuration

Next.js App Router requires a dedicated client component to configure Amplify for browser-side operations:

// components/ConfigureAmplifyClientSide.tsx
"use client";
import { Amplify } from "aws-amplify";
import outputs from "@/amplify_outputs.json";

Amplify.configure(outputs, { ssr: true });

export default function ConfigureAmplifyClientSide() {
  return null;
}

Import in your root layout:

// app/layout.tsx
import ConfigureAmplifyClientSide from "@/components/ConfigureAmplifyClientSide";

export default function RootLayout({ children }: { children: React.ReactNode }) {
  return (
    <html>
      <body>
        <ConfigureAmplifyClientSide />
        {children}
      </body>
    </html>
  );
}

Why? In App Router, layout.tsx is a server component. Client components need Amplify.configure() to run in the browser. Without this, you get "Auth UserPool not configured" errors.

Vue — src/main.js:

import { Amplify } from 'aws-amplify';
import outputs from '../amplify_outputs.json';
Amplify.configure(outputs);

Angular — src/main.ts:

import { Amplify } from 'aws-amplify';
import outputs from '../amplify_outputs.json';
Amplify.configure(outputs);

Next.js Pages Router

Pages Router does NOT need { ssr: true } in _app.tsx. Instead, configure per-file where you need server-side access:

// pages/api/protected.ts or getServerSideProps
import { Amplify } from 'aws-amplify';
import outputs from '@/amplify_outputs.json';
Amplify.configure(outputs, { ssr: true });

Key difference: App Router uses a global client component. Pages Router configures per-file.

<Authenticator.Provider> is required in layout.tsx for auth context.

React Native

React Native uses the same aws-amplify JS package as web frameworks (it is part of amplify-js, not the native mobile SDKs). All web APIs apply to RN with the additions below.

Required Packages

npm install aws-amplify @aws-amplify/react-native \
  @react-native-async-storage/async-storage \
  react-native-get-random-values

@react-native-async-storage/async-storage is required — the Amplify SDK uses it for token persistence and will fail at runtime without it.

Configure Entry Points

No plugin registration needed — configure only.

React Native (Expo) — App.tsx:

import 'react-native-get-random-values';  // MUST be first
import { Amplify } from 'aws-amplify';
import outputs from './amplify_outputs.json';
Amplify.configure(outputs);

React Native (Bare CLI) — index.js (before AppRegistry.registerComponent):

import 'react-native-get-random-values';  // MUST be first
import { Amplify } from 'aws-amplify';
import outputs from './amplify_outputs.json';
Amplify.configure(outputs);

React Native Pitfalls

• Import order: react-native-get-random-values must be the FIRST import in the entry file, before aws-amplify. Reversing the order causes cryptographic failures at runtime.
• Missing AsyncStorage: Without @react-native-async-storage/async-storage, auth tokens are not persisted and users must re-authenticate on every app restart.

SvelteKit

Configure Amplify in the client hooks file:

// src/hooks.client.ts
import { Amplify } from 'aws-amplify';
import outputs from '../amplify_outputs.json';

Amplify.configure(outputs);

Note: No @aws-amplify/ui-* components exist for Svelte. Use core APIs directly.

Unsupported Frameworks (Astro, Solid, etc.)

For frameworks without official Amplify support:

1. Use npm create amplify@latest -y to scaffold the backend (works in any project)
2. Configure Amplify inside a client-side component (not at build time)

Astro

Amplify is client-side only in Astro. Create a React component (no Astro syntax):

// src/components/AuthenticatedApp.tsx
import { Amplify } from 'aws-amplify';
import { Authenticator } from '@aws-amplify/ui-react';
import outputs from '../amplify_outputs.json';

Amplify.configure(outputs);

export default function AuthenticatedApp() {
  return (
    <Authenticator>
      {({ signOut, user }) => <main>Hello {user?.username}</main>}
    </Authenticator>
  );
}

Use in an Astro page with client:only:

---
// src/pages/index.astro — no Amplify imports here
---
<html>
  <body>
    <AuthenticatedApp client:only="react" />
  </body>
</html>

Must use client:only="react" (NOT client:load) to avoid SSR hydration errors.

Links

All documentation links use react as the default platform slug. Replace /react/ in any URL with your target framework:

• Amplify Docs for LLMs
• Amplify Docs
• How Amplify Works
• CLI Commands
• React Quickstart
• Next.js Quickstart
• Angular Quickstart
• Vue Quickstart
• React Native Quickstart