> For the complete documentation index, see [llms.txt](/llms.txt).

[BitTasker](https://bittasker.com/) is a freelance marketplace on Bitcoin and Nostr. 
The BitTasker app provides an embedded rBTC wallet for the Rootstock Mainnet.

The open-source [`@bittasker/wallet-core`](https://www.npmjs.com/package/@bittasker/wallet-core) package is the TypeScript SDK behind that wallet. 
Install it in your web or mobile app to manage rBTC on Rootstock and route Lightning and Liquid swaps through [Boltz](https://boltz.exchange/). 
The SDK also supports Rootstock Testnet and Regtest for development.

For the complete API reference, see the [wallet-core repository README](https://github.com/BitTasker/wallet-core).

## When to use this SDK

Use `@bittasker/wallet-core` when you need:

- BIP39/BIP44 HD wallets on Rootstock mainnet, testnet, or regtest
- rBTC balances, transfers, and transaction history on Rootstock
- Lightning and Liquid swaps into rBTC through [Boltz](https://boltz.exchange/)
- A TypeScript library for React Native, Capacitor, Ionic, or web

## Prerequisites

- Node.js 18+
- A BIP39 mnemonic stored securely (never hardcode in source)
- For testnet work: [tRBTC from the faucet](https://faucet.rootstock.io/)

## Wallet compatibility

| Feature | Value |
| :--- | :--- |
| EIP-55 checksums | Yes |
| Derivation path | `m/44'/60'/0'/0/0` |
| Customizable dPath | No |
| Rootstock networks | Mainnet (BitTasker app); Wallet SDK also supports Testnet and Regtest |
| BitTasker app platforms | Android (Google Play, Zapstore), Web (iOS coming soon) |

:::info[Roadmap]

BitTasker does not currently support MetaMask, hardware wallets, Bitcoin, USDT, or rBTC/USDT swaps. These features are on the roadmap. 
Check the [wallet-core repository](https://github.com/BitTasker/wallet-core) for future releases.

:::

## Get Started

### Installation

```bash
npm install @bittasker/wallet-core
```

### Quick Start

Import `WalletManager`, pass your network and mnemonic, then read balances or send rBTC.

```javascript

const walletManager = new WalletManager({
  network: 'testnet',
  mnemonic: await getSecureMnemonic(),
});

await walletManager.initialize();

const balances = await walletManager.getBalances();
console.log('rBTC:', balances.rsk.rbtc);

const txHash = await walletManager.rskWallet.send(
  '0x742d35Cc6634C0532925a3b844Bc9e7595f0bEb',
  '0.01',
);
console.log('Transaction:', txHash);
```

Replace `getSecureMnemonic()` with your app’s secure storage. Load mnemonics from a keystore, OS secure enclave, or equivalent. Do not commit seed phrases to source control.

### Read addresses and balances

```javascript
const addresses = walletManager.getAddresses();
console.log('Rootstock address:', addresses.rsk);

const rskBalance = await walletManager.rskWallet.getBalance();
console.log('Balance:', rskBalance.formatted, 'rBTC');
```

### Custom Rootstock RPC

Point the SDK at your own node or an RPC provider when the default endpoints are not enough.

```javascript
const walletManager = new WalletManager({
  network: 'mainnet',
  mnemonic: await getSecureMnemonic(),
  rskConfig: {
    rpcUrl: 'https://public-node.rsk.co',
    explorerApiUrl: 'https://rootstock.blockscout.com/api',
  },
});
```

See [Rootstock RPC API](/developers/rpc-api/rootstock/setup/) for provider options.

### Lightning and Liquid swaps

The SDK routes Lightning and Liquid swaps through Boltz. Users hold rBTC on Rootstock as the settlement asset, in the same role L-BTC plays on Liquid in wallets such as Aqua.

```javascript
const swap = await walletManager.reverseSwapService.createReverseSwap({
  amountSats: 100000,
  rbtcAddress: walletManager.rskWallet.getAddress(),
  walletSigner: walletManager.rskWallet.getWallet(),
});

console.log('Pay this Lightning invoice:', swap.invoice);
console.log('Swap ID:', swap.swapId);
```

Check swap limits before you build production flows:

```javascript
const limits = await walletManager.getSwapLimits();
console.log('Lightning min:', limits.lightning.minimal, 'sats');
```

## Security Best Practices

Refer to the [BitTasker Wallet Core Security Best Practices](https://github.com/BitTasker/wallet-core#security-best-practices).

- Store mnemonics in secure storage, not in plain text or environment variables checked into git.
- Validate recipient addresses with `ethers.isAddress()` before you send rBTC.
- Test on Rootstock Testnet before mainnet deployments.
- Report security issues to [security@bittasker.com](mailto:security@bittasker.com).

## Resources

Use these links for the BitTasker app, source code, and npm package.

- [BitTasker app](https://bittasker.com/)
- [wallet-core on GitHub](https://github.com/BitTasker/wallet-core)
- [@bittasker/wallet-core on npm](https://www.npmjs.com/package/@bittasker/wallet-core)

## Next steps

- [Configure MetaMask for Rootstock](/dev-tools/wallets/metamask/) if your dApp also supports browser extension wallets
- [rBTC concepts](/concepts/rbtc/) for peg mechanics and gas
- [Rootstock RPC API](/developers/rpc-api/rootstock/setup/) for production RPC endpoints