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Overview

The BitcoinModule provides native Bitcoin operations including message signing, PSBT signing, sending Bitcoin, and balance queries. Access it via DynamicSDK.instance.bitcoin.

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Prerequisites

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Get Balance

Query the Bitcoin balance (in satoshis) for a wallet. 
final sdk = DynamicSDK.instance;
final wallet = sdk.wallets.userWallets.first;

final balance = await sdk.bitcoin.getBalance(
  walletId: wallet.id,
);
print('Balance: $balance satoshis');

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Sign a Message

Sign a message using the connected Bitcoin wallet. Supports optional protocol and addressType parameters. 
final signature = await sdk.bitcoin.signMessage(
  walletId: wallet.id,
  message: 'Hello, Bitcoin!',
);
print('Signature: $signature');

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With Protocol and Address Type

// Using BIP-322 simple protocol with payment address
final signature = await sdk.bitcoin.signMessage(
  walletId: wallet.id,
  message: 'Hello, Bitcoin!',
  protocol: 'bip322-simple', // or 'ecdsa'
  addressType: 'payment',     // or 'ordinals'
);
ParameterTypeDescription
walletIdStringThe wallet ID to sign with
messageStringThe message to sign
protocolString?Signing protocol: ecdsa or bip322-simple
addressTypeString?Address type: payment or ordinals

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Send Bitcoin

Send Bitcoin to a recipient address. The amount is specified in satoshis. 
final txId = await sdk.bitcoin.sendBitcoin(
  walletId: wallet.id,
  recipientAddress: 'bc1qxy2kgdygjrsqtzq2n0yrf2493p83kkfjhx0wlh',
  amount: '10000', // in satoshis
  feePriority: 'medium', // optional: 'high', 'medium', or 'low'
);
print('Transaction ID: $txId');
ParameterTypeDescription
walletIdStringThe wallet ID to send from
recipientAddressStringThe recipient Bitcoin address
amountStringAmount in satoshis
feePriorityString?Fee priority: high, medium, or low

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Build a PSBT

Build an unsigned Partially Signed Bitcoin Transaction (PSBT) without broadcasting it. 
final unsignedPsbt = await sdk.bitcoin.buildPsbt(
  walletId: wallet.id,
  recipientAddress: 'bc1qxy2kgdygjrsqtzq2n0yrf2493p83kkfjhx0wlh',
  amount: '10000',
  feePriority: 'medium',
);
print('Unsigned PSBT (base64): $unsignedPsbt');

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Sign a PSBT

Sign a PSBT using the connected wallet. 
final signedPsbt = await sdk.bitcoin.signPsbt(
  walletId: wallet.id,
  request: {
    'unsignedPsbtBase64': unsignedPsbt,
  },
);
print('Signed PSBT: $signedPsbt');

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Sign Multiple PSBTs

Batch-sign multiple PSBTs in a single call. 
final signedPsbts = await sdk.bitcoin.signPsbts(
  walletId: wallet.id,
  requests: [
    {'unsignedPsbtBase64': psbt1},
    {'unsignedPsbtBase64': psbt2},
  ],
);
print('Signed ${signedPsbts.length} PSBTs');

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Send Raw Transaction

Broadcast a raw transaction hex to the Bitcoin network. 
final txId = await sdk.bitcoin.sendRawTransaction(
  walletId: wallet.id,
  rawTransaction: '0200000001...', // raw tx hex
);
print('Transaction ID: $txId');

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Complete Example

import 'package:dynamic_sdk/dynamic_sdk.dart';

Future<void> bitcoinExample() async {
  final sdk = DynamicSDK.instance;
  final wallet = sdk.wallets.userWallets.first;

  // Check balance
  final balance = await sdk.bitcoin.getBalance(walletId: wallet.id);
  print('Balance: $balance satoshis');

  // Sign a message
  final signature = await sdk.bitcoin.signMessage(
    walletId: wallet.id,
    message: 'Verify wallet ownership',
  );
  print('Signature: $signature');

  // Build and sign a PSBT
  final unsignedPsbt = await sdk.bitcoin.buildPsbt(
    walletId: wallet.id,
    recipientAddress: 'bc1q...',
    amount: '5000',
  );

  final signedPsbt = await sdk.bitcoin.signPsbt(
    walletId: wallet.id,
    request: {'unsignedPsbtBase64': unsignedPsbt},
  );
  print('Signed PSBT: $signedPsbt');

  // Or send directly
  final txId = await sdk.bitcoin.sendBitcoin(
    walletId: wallet.id,
    recipientAddress: 'bc1q...',
    amount: '5000',
    feePriority: 'medium',
  );
  print('Sent! TX: $txId');
}

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API Reference

MethodReturnsDescription
getBalanceFuture<String>Get wallet balance in satoshis
signMessageFuture<String>Sign a message
sendBitcoinFuture<String>Send BTC, returns transaction ID
buildPsbtFuture<String>Build unsigned PSBT (base64)
signPsbtFuture<String>Sign a single PSBT
signPsbtsFuture<List<String>>Sign multiple PSBTs
sendRawTransactionFuture<String>Broadcast raw transaction hex

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Next Steps