Ark — Ark Protocol¶

Ark protocol wallet: offchain payments, boarding, and settlements.

Import: package:bull_sdk/ark.dart

ArkWallet¶

Core class for Ark protocol operations.

Initialization¶

final wallet = await ark.ArkWallet.init(
  secretKey: secretKey,      // List<int> (32 bytes)
  network: 'mainnet',        // or 'testnet'
  esplora: 'https://esplora.blockstream.info',
  server: 'https://arkserver.example.com',
  boltz: 'https://boltz.exchange',
);

Addresses¶

// Offchain Ark address
final offchainAddr = wallet.offchainAddress();

// Onchain boarding address
final onchainAddr = wallet.onchainAddress();

// Boarding address (same as onchain, for boarding UTXOs)
final boardingAddr = wallet.boardingAddress();

Sending¶

// Send offchain (Ark-to-Ark, instant)
final txid = await wallet.sendOffChain(
  address: 'ark1q...',
  sats: BigInt.from(100000),
);

// Send onchain (standard Bitcoin/Liquid transaction)
final txid = await wallet.sendOnChain(
  address: 'bc1q...',
  sats: BigInt.from(100000),
);

Settlements¶

// Settle pending offchain transactions
await wallet.settle(selectRecoverableVtxos: true);

// Settle boarding transactions (onchain → offchain)
final status = await wallet.settleBoardingTransactions(
  selectRecoverableVtxos: true,
);

// Check boarding status
final boardingStatus = await wallet.getBoardingStatus();
final canSettle = await wallet.canSettleBoarding();

Balance and History¶

final balance = await wallet.balance();
// Returns ArkBalance

final history = await wallet.transactionHistory();
// Returns List<ArkTransaction>

ArkTransaction¶

Union type representing different transaction states:

enum ArkTransaction {
  Boarding {
    String txid;
    int sats;
    int? confirmedAt;
  },
  Commitment {
    String txid;
    int sats;
    int createdAt;
  },
  Redeem {
    String txid;
    int sats;
    bool isSettled;
    int createdAt;
  },
}

Variant	Meaning
`Boarding`	Onchain UTXO awaiting settlement to offchain
`Commitment`	Offchain commitment created
`Redeem`	Offchain redemption (settled or pending)

Server Info¶

final info = wallet.serverInfo();
// Returns ServerInfo with server details

Gotchas¶

Secret key: Must be exactly 32 bytes. Store securely — it controls the wallet.
Boarding delay: Boarding transactions require confirmation before they can be settled. Check canSettleBoarding() before attempting settlement.
Recoverable VTXOs: When selectRecoverableVtxos: true, the wallet selects UTXOs that can be recovered if the server goes offline.
Network strings: Ark uses string network identifiers ('mainnet'/'testnet'), not enum values like LWK.