The Complete Dart SDK for Polkadot & Substrate

Build powerful blockchain applications with type-safe Dart & Flutter

Get started in minutes • Perfect for Flutter apps • Production ready

---

Polkadart is a comprehensive Dart/Flutter SDK that provides everything you need to build decentralized applications on Polkadot, Substrate, and other compatible blockchain networks. With type-safe APIs, automatic code generation, and Flutter-first design, it's the most developer-friendly way to integrate blockchain functionality into your Dart applications.

This library is funded by Web3 Foundation via their Open Grants Program

✨ Why Polkadart?

🚀 Developer-First Experience

• Type-Safe Everything: Auto-generated types from chain metadata ensure compile-time safety
• Flutter Ready: Built from the ground up for mobile and cross-platform development
• Intuitive APIs: Clean, idiomatic Dart interfaces that feel natural to use
• Comprehensive Docs: Extensive documentation with real-world examples

⚡ Feature Complete

• Universal Compatibility: Works with any Substrate-based blockchain
• Smart Contracts: Full support for ink! smart contract interactions
• Real-time Subscriptions: WebSocket support for live blockchain data
• Complete Cryptography: All signature schemes (sr25519, ed25519, ecdsa) included
• Advanced Features: Batch transactions, multi-sig, custom RPCs, and more

🔒 Production Ready

• Battle-Tested: Powers production wallets and dApps with millions of transactions
• High Performance: Optimized SCALE codec with minimal overhead
• Security First: Comprehensive key management and secure signing
• Active Maintenance: Regular updates and active community support
• Web3 Foundation Backed: Official grant recipient ensuring long-term sustainability

🚀 Quick Start

1. Install Polkadart

dependencies:
  polkadart: ^0.7.0
  polkadart_keyring: ^0.7.0

2. Connect & Query

import 'package:polkadart/polkadart.dart';

// Connect to Polkadot
final provider = Provider.fromUri(Uri.parse('wss://rpc.polkadot.io'));
final api = await ApiPromise.create(provider);

// Query account balance
final account = '15oF4uVJwmo4TdGW7VfQxNLavjCXviqxT9S1MgbjMNHr6Sp5';
final balance = await api.query.system.account(account);

print('Free balance: ${balance.data.free}');

3. Send Transactions

import 'package:polkadart_keyring/polkadart_keyring.dart';

// Create a wallet
final keyring = Keyring();
final alice = await keyring.fromMnemonic('//Alice');

// Send a transfer
final tx = api.tx.balances.transfer(
  dest: '14E5nqKAp3oAJcmzgZhUD2RcptBeUBScxKHgJKU4HPNcKVf3',
  value: BigInt.from(10).pow(12), // 1 DOT
);

final hash = await tx.signAndSend(alice);
print('Transaction hash: $hash');

📦 Packages

This repository is a monorepo containing the complete Polkadart ecosystem:

Core Packages

Package	Description	Version
polkadart	Main SDK for Substrate/Polkadot interaction
polkadart_keyring	Key management and account handling

Developer Tools

Package	Description	Version
polkadart_cli	Generate typed APIs from chain metadata
ink_cli	Generate typed interfaces for smart contracts

Low-Level Primitives

Package	Description	Version
polkadart_scale_codec	SCALE codec implementation
substrate_metadata	Runtime metadata parsing
ink_abi	ink! ABI encoding/decoding

Cryptography

Package	Description	Version
sr25519	Schnorrkel signature scheme
secp256k1_ecdsa	ECDSA operations
ss58	SS58 address encoding
substrate_bip39	BIP39 mnemonic generation

📚 Documentation

Getting Started

• Installation Guide
• Quick Start Tutorial
• API Reference
• Examples

Advanced Topics

• Type Generation
• Smart Contracts
• Custom RPCs
• Multi-signature

Package Documentation

• polkadart
• polkadart_cli
• polkadart_keyring
• polkadart_scale_codec
• substrate_metadata
• ink_abi
• ink_cli
• sr25519
• secp256k1_ecdsa
• ss58
• substrate_bip39

🤝 Community & Support

Get Help 💬 Matrix Chat - Developer discussions 📖 API Documentation - Complete reference 🐛 Issue Tracker - Report bugs 💡 Discussions - Feature requests

Showcase 📱 Encointer Wallet - Production wallet 🏛️ Polkadot Forum - Official announcement 🎮 Example Apps - Sample code 🚀 Your App Here! - Share your project

🎯 Contributing

We welcome contributions from developers of all skill levels! Here's how you can help:

🐛 Report & Fix Report bugs Fix issues Improve tests Update docs

✨ Enhance Add features Write examples Create tutorials Translate docs

🚀 Share Star the repo Share projects Write articles Join discussions

Every contribution matters! Check our Contributing Guide for details.

👥 Contributors

A heartfelt thank you to all the amazing contributors who have helped build Polkadart! emoji key

Leonardo Custodio 💻 ⚠️ 👀 💬 🚧 💡 📖 🐛	justkawal 💻 ⚠️ 👀 🚧 💡 🐛	Lohann Paterno Coutinho Ferreira 💻 ⚠️ 👀 💡 🐛	Gabriel Okura 💻 ⚠️ 💡	clangenb 💻 ⚠️ 🐛 💬	Bruno Pastre 👀	weiwei 💻 🐛
Burnww 💻 🐛	Aviv Eyal 💻 🐛	jpnovochadlo 💼 🎨 📖	Talles 💻 📖	Burak 💻	vjrj 💻

This project follows the all-contributors specification. Contributions of any kind welcome! ❤️

📜 License

This project is licensed under the Apache 2.0 License

🚀 What's Next?

Ready to build your next blockchain application? Here's where to go:

• 📖 Read the Documentation - Complete guides and tutorials
• 💻 Explore Examples - Working code samples
• 💬 Join the Community - Get help and share ideas
• ⭐ Star the Project - Show your support!

---

Build the future of Web3 with Dart & Flutter 🚀