Flutter SDK v6 Migration Guide

This guide upgrades Embedded Wallets Flutter SDK integrations from v3 through v5 directly to v6.

AI-assisted migration

For the best results, install the MetaMask Embedded Wallets skill and MCP server before you migrate. See Build with AI for setup (npx skills add web3auth/skill and MCP at https://mcp.web3auth.io).

Copy the prompt below into your AI coding assistant (Cursor, Claude Code, Codex, Antigravity, or similar):

Migrate my MetaMask Embedded Wallets Flutter (web3auth_flutter) project to v6.

Before changing code:
1. Use the web3auth skill and MCP tools (search_docs, get_doc, get_example, get_sdk_reference).
2. Read the migration guide: https://docs.metamask.io/embedded-wallets/migration-guides/flutter-v6
3. Detect my current SDK version from pubspec.yaml and list which breaking changes apply.

Then migrate my codebase directly to v6:
- Update web3auth_flutter to ^6.1.2 in pubspec.yaml.
- Set Android minSdkVersion to 26 and compileSdkVersion to 34.
- Replace getSignResponse() with the response returned from request().
- Remove any setResultUrl calls (removed in v4).
- Use Web3AuthFlutter.setCustomTabsClosed() on Android for login cancellation handling.
- Configure platform-specific redirectUrl (Android: {SCHEME}://{HOST}/auth, iOS: {bundleId}://auth).
- Do not change my Client ID or Sapphire network unless I ask; that would change wallet addresses.

After migrating, list every file you changed and any manual dashboard steps I still need to do.

tip

Use planning mode (where available) for the initial prompt. Review the plan before generating code; config mistakes can change wallet addresses in production.

Install v6

Update pubspec.yaml:

dependencies:
  web3auth_flutter: ^6.1.2

Or run:

flutter pub add web3auth_flutter

Set Android minSdkVersion to 26 and compileSdkVersion to 34:

android {
    compileSdkVersion 34

    defaultConfig {
        minSdkVersion 26
    }
}

Add JitPack to your project-level Gradle file and configure platform redirects. See the Flutter SDK get started for Android and iOS setup.

Breaking changes

Apply the sections below that match your current version. If you're already on v5, focus on the v6 changes.

setResultUrl removed (from v4)

v4 removes setResultUrl. On Android, use Web3AuthFlutter.setCustomTabsClosed() in your app lifecycle observer to detect when the user closes the custom tab:

@override
void didChangeAppLifecycleState(final AppLifecycleState state) {
  if (state == AppLifecycleState.resumed) {
    Web3AuthFlutter.setCustomTabsClosed();
  }
}

Register the observer in initState with WidgetsBinding.instance.addObserver(this).

request and sign response (from v4, updated in v6)

From v4, use Web3AuthFlutter.request() with ChainConfig for templated signing screens. From v6, getSignResponse() is removed. Read the result from request() directly:

try {
  List<dynamic> params = [];
  params.add("Hello, Web3Auth from Flutter!");
  params.add("<User Address in Hex>");

  final response = await Web3AuthFlutter.request(
    ChainConfig(
      chainId: "0x1",
      rpcTarget: "https://mainnet.infura.io/v3/<YOUR_KEY>",
    ),
    "personal_sign",
    params,
  );

  log(response.toString());
} on UserCancelledException {
  log("User cancelled.");
} catch (e) {
  log("Unknown exception occurred");
}

v6 changes

• getSignResponse() removed: use the return value of request() (see example above).
• Minimum Android SDK 26: update minSdkVersion in your app-level Gradle file.

v6 also adds support for Web3Auth Auth Service v9 and Wallet Services v3 (including swap in the prebuilt wallet UI).

New APIs (non-breaking)

These APIs were added in v4. If you're upgrading from v3, adopt them as part of your v6 migration.

API	Added in	Purpose
enableMFA()	v4	Initiate MFA setup for logged-in users
launchWalletServices()	v4	Open the templated wallet UI
request()	v4	Sign transactions with confirmation screens
SMS Passwordless login	v4	Provider.sms_passwordless with login_hint
Farcaster login	v4	Provider.farcaster

Example launchWalletServices:

await Web3AuthFlutter.launchWalletServices(
  ChainConfig(
    chainId: "0x1",
    rpcTarget: "https://mainnet.infura.io/v3/<YOUR_KEY>",
  ),
);

See Wallet Services and MFA for usage details.

Summary table

Area	v3 and earlier	v4–v5	v6
setResultUrl	Used on Android	Removed	Removed
Sign result	N/A	getSignResponse()	Return value of request()
Android minSdk	24	24	26
Wallet Services	N/A	Available	Wallet Services v3

Next steps

• Flutter SDK get started
• Build with AI for ongoing integration help
• Release notes