The Complete Dart/Flutter SDK

Build Cross-Platform Blockchain Apps with Polkadot

Type-safe, performant, and production-ready SDK for building decentralized applications on Polkadot and Substrate-based chains. One codebase for mobile, web, and desktop.

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11 Packages

13+ Contributors

100% Dart Native

Web3 Foundation Grant

import 'package:polkadart/polkadart.dart';

void main() async {
    final uri = Uri.parse('wss://rpc.polkadot.io');
    final provider = Provider.fromUri(uri);

    final stateApi = StateApi(provider);
    final runtimeVersion = await stateApi.getRuntimeVersion();

    print(runtimeVersion.toJson());
}

Why Developers Choose Polkadart

Polkadart is a comprehensive Dart/Flutter SDK for Polkadot, providing everything you need to build robust blockchain applications with type safety and excellent developer experience.

Developer-First Design

Built by developers for developers, with intuitive APIs, excellent documentation, and comprehensive examples.

100% Type-Safe

Auto-generated types from chain metadata ensure compile-time safety and eliminate runtime errors.

True Cross-Platform

Write once, deploy everywhere. Native performance on iOS, Android, Web, macOS, Windows, and Linux.

Lightning Fast

Native Dart compilation and optimized SCALE codec deliver exceptional performance on all platforms.

Smart Contract Ready

Full support for ink! smart contracts with type-safe contract calls and event handling.

Well-Maintained

Actively developed with comprehensive test coverage, regular updates, and responsive community support.

Type Safety Meets Blockchain

Never Ship Runtime Errors Again

Polkadart generates strongly-typed APIs from chain metadata, ensuring your code is always in sync with the blockchain runtime. Catch errors at compile-time, not in production.

Auto-Generated Types

Every pallet, extrinsic, and storage item is type-safe. IDE auto-completion guides you through the entire API, making blockchain development as easy as traditional app development.

import 'package:demo/generated/polkadot/polkadot.dart';
import 'package:polkadart/polkadart.dart' show Provider;

Future<void> main(List<String> arguments) async {
  final provider = Provider.fromUri(Uri.parse('wss://rpc.polkadot.io'));
  final polkadot = Polkadot(provider);
  final runtime = await polkadot.rpc.state.getRuntimeVersion();

  print(runtime.toJson());
}

import 'package:polkadart_keyring/polkadart_keyring.dart';

Future<void> main(List<String> arguments) async {
  final keyring = Keyring();
  final keyPair = await keyring.fromUri('//Alice');

  print('Alice address: ${keyPair.address}');
}

Secure by Design

Built with security best practices, including secure key management, proper signature verification, and protection against common blockchain vulnerabilities.

Getting Started with Polkadart

Install Dependencies

dart pub add polkadart polkadart_cli

Choose Your Blockchain

polkadart:
  output_dir: lib/generated
  chains:
    polkadot: wss://rpc.polkadot.io

Generate Blockchain Code

dart run polkadart_cli:generate -v

Start Building

View Full Guide

import 'package:polkadart/polkadart.dart';
import 'package:ss58/ss58.dart';
import './generated/polkadot/polkadot.dart';
import './generated/polkadot/types/frame_system/account_info.dart';

Future<void> main(List<String> arguments) async {
  final address = '1zugcag7cJVBtVRnFxv5Qftn7xKAnR6YJ9x4x3XLgGgmNnS';
  final provider = Provider.fromUri(Uri.parse('wss://rpc.polkadot.io'));
  final api = Polkadot(provider);

  Address wallet = Address.decode(address);
  AccountInfo accountInfo = await api.query.system.account(wallet.pubkey);

  print("""
    Free balance: ${accountInfo.data.free}
    Reserved balance: ${accountInfo.data.reserved}
    Nonce: ${accountInfo.nonce}
  """);
}

Works with Every Substrate Chain

Universal Compatibility

Connect to Polkadot, Kusama, or any Substrate-based parachain. Auto-generate types specific to each chain's runtime for perfect compatibility.

import 'package:polkadart/provider.dart';
import './generated/assethub/assethub.dart';
import './generated/people/people.dart';
import './generated/polkadot/polkadot.dart';

Future<void> main(List<String> arguments) async {
  final polkadot =
      Polkadot(Provider.fromUri(Uri.parse('wss://rpc.polkadot.io')));
  final people = People(
      Provider.fromUri(Uri.parse('wss://polkadot-people-rpc.polkadot.io')));
  final assetHub = Assethub(
      Provider.fromUri(Uri.parse('wss://polkadot-asset-hub-rpc.polkadot.io')));

  print('${await polkadot.query.session.validators()}');
  print('${await people.query.identity.registrars()}');
  print('${await assetHub.query.assets.nextAssetId()}');
}

Smart Contract Development

Deploy, call, and listen to events from ink! smart contracts with full type safety and automatic ABI parsing.

import 'dart:typed_data';
import 'package:polkadart/polkadart.dart';
import 'generated_flipper.dart';

Future<void> main(List<String> arguments) async {
  final contract = Address.decode('5DXR2MxThkyZvG3s4ubu9yRdNiifchZ9eNV8i6ErGx6u1sea')
  final provider = Provider.fromUri(Uri.parse('ws://127.0.0.1'));

  final contract = Contract(
    provider: provider,
    address: contract.pubkey,
  );

  // Call the get method
  print('Get value: ${await contract.get()}');
}

Build for Any Screen

Create responsive applications that adapt seamlessly across mobile, tablet, and desktop. With Flutter's powerful UI framework and Polkadart's blockchain capabilities, deploy everywhere your users are.

import 'package:flutter/material.dart';
import 'package:polkadart_keyring/polkadart_keyring.dart';

class PolkadotApp extends StatefulWidget {
  const PolkadotApp({super.key});

  @override
  State<PolkadotApp> createState() => _PolkadotAppState();
}

class _PolkadotAppState extends State<PolkadotApp> {
  final keyring = Keyring();
  List<Account> accounts = [];

  generateNewAccount() async {
    final derivationPath =
        '//Alice${accounts.isNotEmpty ? '//${accounts.length}' : ''}';

    final wallet = await keyring.fromUri(derivationPath, addToPairs: true);
    final account = Account(wallet.address, derivationPath);

    setState(() {
      accounts.add(account);
    });
  }

  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      debugShowCheckedModeBanner: false,
      theme: ThemeData(
        primarySwatch: MaterialColor(0xFFFF2670, <int, Color>{
          50: polkadotPink,
          100: polkadotPink,
          200: polkadotPink,
          300: polkadotPink,
          400: polkadotPink,
          500: polkadotPink,
          600: polkadotPink,
          700: polkadotPink,
          800: polkadotPink,
          900: polkadotPink,
        }),
        elevatedButtonTheme: ElevatedButtonThemeData(
          style: ElevatedButton.styleFrom(
            foregroundColor: Colors.white,
            backgroundColor: polkadotPink,
            textStyle: TextStyle(
              color: Colors.white,
              fontSize: 14,
              fontWeight: FontWeight.w500,
            ),
          ),
        ),
      ),
      home: Scaffold(
        body: Column(
          crossAxisAlignment: CrossAxisAlignment.center,
          children: [
            Padding(
              padding: const EdgeInsets.only(top: 20, bottom: 3),
              child: Text('Generate wallets by clicking on the button'),
            ),
            Divider(),
            Expanded(
              child: ListView.builder(
                itemCount: accounts.length,
                itemBuilder: (BuildContext context, int index) {
                  return Column(
                    mainAxisSize: MainAxisSize.min,
                    children: [
                      ListTile(
                        minTileHeight: 10,
                        enabled: true,
                        title: Text(
                          accounts[index].encodedAddress,
                          style: const TextStyle(fontSize: 13),
                        ),
                        subtitle: Text(
                          accounts[index].derivationPath,
                          style: TextStyle(fontSize: 10),
                        ),
                      ),
                      const Divider(),
                    ],
                  );
                },
              ),
            ),
            Padding(
              padding: const EdgeInsets.only(bottom: 12.0),
              child: ElevatedButton(
                onPressed: () async => await generateNewAccount(),
                child: const Text('Generate a new account'),
              ),
            ),
          ],
        ),
      ),
    );
  }
}

class Account {
  final String encodedAddress;
  final String derivationPath;

  Account(this.encodedAddress, this.derivationPath);
}

Color polkadotPink = const Color(0xFFFF2670);

void main() {
  runApp(const PolkadotApp());
}