LWK — Liquid Wallet Kit¶

Liquid network wallet operations: addresses, transactions, balances, and PayJoin.

Import: package:bull_sdk/lwk.dart

Wallet¶

Core class for Liquid wallet management.

Initialization¶

final wallet = await lwk.Wallet.init(
  network: lwk.LiquidNetwork.mainnet,
  dbpath: '/path/to/wallet.db',
  descriptor: descriptor,
);

Addresses¶

// Get address at specific index
final addr = await wallet.address(index: 0);

// Get last unused address
final addr = await wallet.addressLastUnused();

Syncing¶

await wallet.sync_(
  electrumUrl: 'blockstream.info:995',
  validateDomain: false,
  stopAtIndex: null,    // null = sync all
  timeout: null,        // no timeout
);

Balances¶

final balances = await wallet.balances();
// Returns List<Balance> — one per asset

Building Transactions¶

L-BTC Transaction¶

final pset = await wallet.buildLbtcTx(
  sats: BigInt.from(100000),
  outAddress: 'lq1qq...',
  feeRate: 1.0,
  drain: false,  // true = send all (drain wallet)
);

Asset Transaction¶

final pset = await wallet.buildAssetTx(
  sats: BigInt.from(5000),
  outAddress: 'lq1qq...',
  feeRate: 1.0,
  asset: 'asset-id-here',
);

PayJoin Transaction¶

final payjoinTx = await wallet.buildPayjoinTx(
  sats: BigInt.from(5000),
  outAddress: 'lq1qq...',
  asset: 'asset-id',
  network: lwk.LiquidNetwork.mainnet,
  isSendAll: false,
);

// Review server fee before signing
print('Server fee: ${payjoinTx.serverFee}');

Signing¶

final signedPset = await wallet.signTx(
  network: lwk.LiquidNetwork.mainnet,
  pset: pset,
  mnemonic: mnemonic,
);

Transaction History¶

final txs = await wallet.txs();
// Returns List<Tx>

UTXOs¶

final utxos = await wallet.utxos();
// Returns List<TxOut>

Descriptor¶

Wallet descriptor for address generation.

final descriptor = await lwk.Descriptor.fromString(
  desc: 'descriptor-string',
);

Supporting Types¶

Type	Description
`LiquidNetwork`	`mainnet` or `testnet`
`Address`	Liquid address with index
`Balance`	Asset balance (asset ID + amount)
`Tx`	Transaction details
`TxOut`	Transaction output (UTXO)
`PayjoinTx`	PayJoin transaction result with server fee

Gotchas¶

Database path: The dbpath must be writable. On mobile, use the app's documents directory.
Sync before operations: Always call sync_() before building transactions or checking balances.
PayJoin fee review: Always review the serverFee in PayjoinTx before signing and broadcasting.
Asset IDs: Liquid assets are identified by hex strings. Use the correct asset ID for asset transactions.