Lux Docs

Burning Tokens (Source Chain)

Call bridgeBurn() on the Bridge contract deployed on the source chain. All destination parameters are committed into the on-chain event.

function bridgeBurn(
    address token,      // Whitelisted ERC20B token
    uint256 amount,     // Amount to transfer
    uint256 toChainId,  // Destination chain ID
    address recipient,  // Recipient on destination chain
    bool vault          // Whether to deposit into vault
) external returns (bytes32 burnId);

The contract emits a BridgeBurned event:

event BridgeBurned(
    bytes32 indexed burnId,
    address indexed token,
    address indexed sender,
    uint256 amount,
    uint256 toChainId,
    address recipient,
    bool vault,
    uint256 nonce
);

Requesting a Signature

Submit the burn transaction hash to the API service. The service parses the on-chain event and returns an EIP-712 signature from the MPC oracle.

// POST /api/signature
const response = await fetch('/api/signature', {
  method: 'POST',
  headers: { 'Content-Type': 'application/json' },
  body: JSON.stringify({
    burnTxHash: '0x...',  // 32-byte hex
    fromChainId: 96369,
    logIndex: 0,
  }),
});

const { claimId, signature, ...claimData } = await response.json();

Minting Tokens (Destination Chain)

Submit the claim data and oracle signature to bridgeMint() on the destination chain.

function bridgeMint(
    ClaimData calldata claim,
    bytes calldata signature
) external returns (bytes32 claimId);

The contract verifies the EIP-712 signature against an authorized oracle address, checks replay protection via the claim ID, and mints tokens to the recipient.

API Endpoints

Endpoint	Method	Description
`/api/signature`	POST	Request claim signature for a burn tx
`/api/claim/:claimId`	GET	Check claim status
`/health`	GET	Service health check

Rate Limits

The API enforces 100 requests per 15 minutes per IP address. All sensitive operations use POST to keep parameters out of URLs and server logs.

Development

# Build and test contracts
cd contracts && pnpm install && pnpm test

# Run API service
cd api && pnpm install && pnpm build && pnpm start

# Run MPC service
cd mpc && pnpm install && pnpm build && pnpm start

Token Transfers