EtherFi Liquid Restaking Integration
EtherFi — largest liquid restaking protocol by TVL ($5B+). Key differentiator: non-custodial approach — validator keys remain with stakers, not EtherFi. Achieved through Distributed Validator Technology (DVT) and specialized key management.
EtherFi Tokens
eETH: native liquid restaking token. Rebasing — balance grows with time receiving rewards.
weETH: wrapped eETH, value-accruing version. Exchange rate weETH/eETH grows. Used in most DeFi protocols (Aave, Morpho, Pendle).
Technical Interfaces
Deposit ETH and Get eETH
interface ILiquidityPool {
function deposit() external payable returns (uint256);
function deposit(address _referral) external payable returns (uint256);
}
// Deposit ETH, get eETH
ILiquidityPool liquidityPool = ILiquidityPool(ETHERFI_LIQUIDITY_POOL);
uint256 eETHAmount = liquidityPool.deposit{value: ethAmount}(referralAddress);
Wrap/Unwrap eETH ↔ weETH
interface IWeETH {
function wrap(uint256 _eETHAmount) external returns (uint256);
function unwrap(uint256 _weETHAmount) external returns (uint256);
function getWeETHByeETH(uint256 _eETHAmount) external view returns (uint256);
function getEETHByWeETH(uint256 _weETHAmount) external view returns (uint256);
}
// Conversion for DeFi protocols
IWeETH weETH = IWeETH(WEETH_ADDRESS);
uint256 weETHAmount = weETH.wrap(eETHAmount);
Withdrawal Request
interface IWithdrawRequestNFT {
function requestWithdraw(uint256 amount, address recipient) external returns (uint256);
}
// Get NFT with pending withdrawal
uint256 requestId = withdrawRequestNFT.requestWithdraw(eETHAmount, msg.sender);
// Wait for finalizeWithdraw (several days)
Chainlink Price Feed for weETH
When using weETH as collateral in DeFi, need price feeds:
// Chainlink weETH/ETH feed
AggregatorV3Interface priceFeed = AggregatorV3Interface(WEETH_ETH_PRICE_FEED);
(, int256 price,,,) = priceFeed.latestRoundData();
// price — in wei per 1 weETH
EtherFi also provides getRate() on weETH contract to get current exchange rate.
EtherFi Points and Loyalty System
EtherFi uses points system for bootstrapping liquidity. API allows verifying and displaying points of users. EtherFi referral programs work via on-chain referral tracking.
Integration of EtherFi into DeFi protocol or wallet — 1-3 weeks. Main work — correct handling of exchange rates and withdrawal flow.