@lendguard/sdk

Framework-agnostic TypeScript SDK for the LendGuard native lending protocol on Solana — built on Ika dWallets for cryptographically-provable cross-chain collateral (SOL and native Bitcoin via Secp256k1 dWallets) and Encrypt FHE for private, anti-MEV risk monitoring.

Install

npm install @lendguard/sdk @solana/web3.js

Peer deps: @solana/web3.js >= 1.95.

What's in 0.3.0

• SOL collateral path — buildBorrowAgainstCollateralIx, buildRepayBorrowIx, buildLiquidatePositionIx, plus admin helpers
• 🆕 BTC collateral path (native Bitcoin via Ika Secp256k1 dWallets) — 8 new instruction builders:
  • buildRegisterBtcVaultIx
  • buildVerifyBtcCustodyProofIx
  • buildRefreshBtcCustodyProofIx
  • buildAttestBtcBalanceIx
  • buildBorrowAgainstBtcCollateralIx
  • buildRepayBtcBorrowIx
  • buildLiquidateBtcPositionIx
  • buildFinalizeBtcLiquidationIx
• All BTC PDA helpers: deriveBtcVaultPda, deriveBtcAttestationPda, deriveBtcBorrowPositionPda, deriveIkaCpiAuthority
• Account decoders for LendingPool, BorrowPosition, AdminPriceFeed, ProtocolState

Quick start — borrow LGUSD against SOL collateral

import {
  buildBorrowAgainstCollateralIx,
  deriveVaultPda,
  LGUSD_MINT_DEVNET,
} from "@lendguard/sdk";
import { Connection, Transaction, PublicKey } from "@solana/web3.js";

const connection = new Connection("https://api.devnet.solana.com", "confirmed");
const owner = wallet.publicKey;
const [vaultPda] = deriveVaultPda(owner, ikaDwalletPubkey);

const { ix } = await buildBorrowAgainstCollateralIx({
  owner,
  vaultPda,
  borrowAssetMint: LGUSD_MINT_DEVNET,
  poolTokenVault,
  borrowerTokenAccount,
  amount: 25_000_000n, // 25 LGUSD (6-decimal)
});

const sig = await connection.sendTransaction(new Transaction().add(ix), [wallet]);

Quick start — register a Bitcoin testnet vault

import {
  buildRegisterBtcVaultIx,
  buildVerifyBtcCustodyProofIx,
  deriveBtcVaultPda,
} from "@lendguard/sdk";

const { ix: registerIx, btcVaultPda } = await buildRegisterBtcVaultIx({
  owner: wallet.publicKey,
  ikaDwallet: ikaDwalletAccount,        // 32-byte Ika dWallet pubkey
  dwalletPubkey: compressedSecp256k1,   // 33 bytes
  bitcoinAddress: "tb1q...",
});

const verifyIx = await buildVerifyBtcCustodyProofIx({
  owner: wallet.publicKey,
  btcVaultPda,
  messageApprovalPda,                   // produced by Ika DKG/signing flow
});

// Combine register + verify in a single transaction.
const tx = new Transaction().add(registerIx, verifyIx);

Quick start — borrow against attested BTC

After an authorized keeper has posted a BitcoinBalanceAttestation:

import { buildBorrowAgainstBtcCollateralIx, LGUSD_MINT_DEVNET } from "@lendguard/sdk";

const { ix } = await buildBorrowAgainstBtcCollateralIx({
  owner: wallet.publicKey,
  btcVaultPda,
  borrowAssetMint: LGUSD_MINT_DEVNET,
  poolTokenVault,
  borrowerTokenAccount,
  amount: 50_000_000n, // 50 LGUSD
});

To repay everything at once (debt + accrued interest, with on-chain dust forgiveness):

import { buildRepayBtcBorrowIx } from "@lendguard/sdk";

const ix = await buildRepayBtcBorrowIx({
  /* ...accounts... */
  amount: (1n << 64n) - 1n,             // u64::MAX → repay everything
});

Devnet program IDs

| Component | Address | |---|---| | LendGuard program | LGUARDxJP9G4QH7uW2GuV5KKqPRkrCZcZ8jKqcQVUWJ | | LGUSD mint | LGUSDcMv5sH6KEqMW9P5GE52f72NgaT9CrLuFA3JTH4 | | Ika dWallet program | 87W54kGYFQ1rgWqMeu4XTPHWXWmXSQCcjm8vCTfiq1oY |

Project links

• Repository: https://github.com/abhishekplus/LendGuard
• Live demo: https://lendguard.vercel.app
• Protocol docs: see /docs in the repo