Light Protocol Dart SDK

Light Protocol SDK for Dart

License Dart Tests

A Dart/Flutter SDK for Light Protocol ZK Compression on Solana.

The Story

I was building a mobile app that needed cheap token transfers on Solana. When I discovered Light Protocol's ZK Compression (1000x cheaper!), I was excited—until I realized there was no Dart SDK. Only TypeScript and Rust.

So I ported it. This is a Dart implementation of @lightprotocol/stateless.js and @lightprotocol/compressed-token, built for Flutter developers who want to use ZK compression without leaving the Dart ecosystem.

What This SDK Does

  • Compress SOL → Store SOL in compressed accounts (way cheaper)
  • Transfer Compressed SOL → Move compressed SOL between accounts
  • Decompress SOL → Convert back to regular SOL when needed
  • Compressed Tokens → Same operations for SPL tokens

Installation

dependencies:
  light_sdk:
    git:
      url: https://github.com/Lightprotocol/light-protocol.git
      path: dart-light

Note: This package depends on the solana package from espresso-cash.

Quick Start

import 'package:light_sdk/light_sdk.dart';
import 'package:solana/solana.dart';

void main() async {
  // Connect to RPC with compression API support
  final rpc = Rpc.create(
    'https://mainnet.helius-rpc.com?api-key=YOUR_KEY',
  );

  // Your wallet
  final wallet = await Ed25519HDKeyPair.fromMnemonic('your mnemonic...');

  // Compress 1 SOL
  final signature = await compress(
    rpc: rpc,
    payer: wallet,
    lamports: BigInt.from(1000000000),
    toAddress: wallet.publicKey,
  );
  print('Compressed! Signature: $signature');

  // Check compressed balance
  final balance = await rpc.getCompressedBalanceByOwner(wallet.publicKey);
  print('Compressed balance: $balance lamports');

  // Transfer to someone
  final recipient = Ed25519HDPublicKey.fromBase58('...');
  await transfer(
    rpc: rpc,
    payer: wallet,
    owner: wallet,
    lamports: BigInt.from(100000),
    toAddress: recipient,
  );
}

API Overview

High-Level Actions

// Compress SOL
await compress(rpc: rpc, payer: wallet, lamports: amount, toAddress: recipient);

// Transfer compressed SOL
await transfer(rpc: rpc, payer: wallet, owner: wallet, lamports: amount, toAddress: recipient);

// Decompress back to regular SOL
await decompress(rpc: rpc, payer: wallet, lamports: amount, recipient: recipient);

RPC Methods

// Get compressed accounts
final accounts = await rpc.getCompressedAccountsByOwner(owner);

// Get compressed balance
final balance = await rpc.getCompressedBalanceByOwner(owner);

// Get validity proof (needed for transactions)
final proof = await rpc.getValidityProof(hashes: [accountHash]);

// Get token balances
final tokens = await rpc.getCompressedTokenBalancesByOwner(owner);

Compressed Tokens

// Create token pool (one-time setup per mint)
final poolInstruction = CompressedTokenProgram.createSplInterface(
  payer: wallet.publicKey,
  mint: mintPubkey,
);

// Mint compressed tokens
final mintInstruction = CompressedTokenProgram.mintTo(
  payer: wallet.publicKey,
  mint: mintPubkey,
  authority: mintAuthority.publicKey,
  amount: BigInt.from(1000000),
  toPubkey: recipient,
  outputStateTreeInfo: treeInfo,
);

// Transfer compressed tokens
final transferInstruction = CompressedTokenProgram.transfer(
  payer: wallet.publicKey,
  inputCompressedTokenAccounts: inputAccounts,
  toAddress: recipient,
  amount: BigInt.from(1000),
  recentInputStateRootIndices: proof.rootIndices,
  recentValidityProof: proof.compressedProof,
);

Examples

Check out the example/ directory:

  • basic_usage.dart - Compress, transfer, and decompress SOL
  • compressed_tokens.dart - Working with compressed SPL tokens
  • advanced_usage.dart - Manual transaction building, validity proofs
  • flutter_integration.dart - Patterns for Flutter apps

Requirements

  • Dart SDK ≥ 3.7.0
  • An RPC endpoint with compression API support (e.g., Helius)

How It Works

Light Protocol uses ZK compression to store account state in Merkle trees instead of on-chain accounts. This means:

  1. No rent - Compressed accounts don't pay rent
  2. Cheaper transactions - State changes are smaller
  3. Same security - Zero-knowledge proofs ensure validity

The trade-off is that you need an indexer (like Photon) to query compressed state. This SDK handles that automatically through the RPC layer.

Contributing

Contributions welcome! Please read CONTRIBUTING.md first.

License

Apache 2.0 - see LICENSE

Built with ☕ and frustration that there was no Dart SDK.

Libraries

light_sdk
Light Protocol SDK for Dart