@lombard.finance/sdk

@lombard.finance/sdk

The official Lombard SDK for Bitcoin staking and LBTC operations across Bitcoin, EVM, Solana, Sui, and Starknet.

Installation

npm install @lombard.finance/sdk

Peer Dependencies

The SDK requires these peer dependencies:

npm install axios@^1 bignumber.js@^9 @bitcoinerlab/secp256k1@1.2.0 bitcoinjs-lib@6.1.5 @layerzerolabs/lz-v2-utilities@3.0.17

Note: viem is included as a direct dependency and does not need to be installed separately.

Quick Start

import { createLombardSDK, Chain, AssetId } from '@lombard.finance/sdk';

// Initialize SDK
const sdk = await createLombardSDK({
  env: 'prod',
  providers: {
    evm: () => window.ethereum,
    bitcoin: () => window.btc,
  },
});

// Create a BTC Stake action
const stake = sdk.chain.btc.stake({
  assetOut: AssetId.LBTC,
  destChain: Chain.ETHEREUM,
});

// Listen to events
stake.on('status-change', (status) => console.log('Status:', status));
stake.on('progress', (progress) => console.log('Progress:', progress));

// Execute the action lifecycle
await stake.prepare({ amount: '0.001', recipient: '0x...' });
await stake.authorize(); // If required
await stake.generateDepositAddress();

// User sends BTC to stake.depositAddress
// Funds auto-mint to LBTC

Configuration

The SDK provides two approaches:

Full SDK (Recommended)

// SDK initialization is async (fetches config)
const sdk = await createLombardSDK({
  env: 'prod',
  providers: { evm: () => window.ethereum },
});

Architecture

The SDK uses an action-based architecture where each operation (stake, unstake, deploy, etc.) is represented as an action object with a consistent lifecycle:

create → prepare → execute → complete

Available Actions

Chain	Action	Description
BTC	sdk.chain.btc.stake()	Stake BTC → LBTC
BTC	sdk.chain.btc.deposit()	Deposit BTC → BTC.b
EVM	sdk.chain.evm.stake()	Stake BTC.b → LBTC
EVM	sdk.chain.evm.unstake()	Burn LBTC → BTC or BTC.b
EVM	sdk.chain.evm.deposit()	Deposit BTC.b → LBTC
EVM	sdk.chain.evm.redeem()	Redeem BTC.b → BTC
EVM	sdk.chain.evm.deploy()	Deploy LBTC/BTC.b to DeFi vaults
EVM	sdk.chain.evm.withdraw()	Withdraw vault shares → LBTC
Solana	sdk.chain.solana.stake()	Stake BTC.b → LBTC
Solana	sdk.chain.solana.unstake()	Burn LBTC → BTC or BTC.b
Solana	sdk.chain.solana.redeem()	Redeem BTC.b → BTC
Sui	sdk.chain.sui.unstake()	Burn LBTC on Sui
Starknet	sdk.chain.starknet.unstake()	Burn LBTC on Starknet

Data API

Query deposits, unstakes, points, and exchange rates:

const deposits = await sdk.api.deposits(address);
const unstakes = await sdk.api.unstakes(address);
const points = await sdk.api.points(address);
const rate = await sdk.api.exchangeRatio();

Playground

Try the SDK interactively at lombard.finance/playground.

The playground provides:

• Live code examples for all actions
• Real wallet connections
• Testnet and mainnet environments
• Step-by-step action execution

Documentation

• Getting Started
• Action Lifecycle
• Migration from v3.x
• Full Documentation Index

Non-EVM Chains

For Solana, Sui, and Starknet, install the chain-specific modules:

# Solana
npm install @lombard.finance/sdk-solana

# Sui
npm install @lombard.finance/sdk-sui

# Starknet
npm install @lombard.finance/sdk-starknet

Register modules when creating the SDK:

import { solanaModule } from '@lombard.finance/sdk-solana';
import { suiModule } from '@lombard.finance/sdk-sui';

const sdk = await createLombardSDK({
  env: 'prod',
  modules: [solanaModule(), suiModule()],
  providers: {
    solana: () => window.solana,
    sui: () => suiWallet,
  },
});

Requirements

• TypeScript: 5.0+
• Node.js: 18+ (ESM support required)
• Browser: Modern browsers with ES2020 support

Environment

Environment	Description	Use For
prod	Production mainnet	Live deployments
testnet	Public testnet	Integration testing
stage	Staging environment	Internal testing

License

MIT Lombard Finance