haikukoten / EthIstanbulContracts

MeowLend Protocol PoC

Lending protocol for memecoins https://ethglobal.com/showcase/meowlend-qgv91

Deploys

polygonZK addresses (mainnet)

lend 0x2a958EFb0dCd381c036675D564c08eB1909C38AC

oracle 0x97eaA69F210426eaC3A391d6d4377cfe85443494

shib 0x7a1adc8340C00AA3Ecdd4Ecf36182Eed5D1BAb0B

accessControlSingleton 0x708071C080E5ceb3cc0fb8fb4fD1034766eAef24

oracleAggregator 0xDF2e747Ae22Ea80B5f6C8f8BA8FDC2FAAC996762

ArbitrumOne addresses (mainnet)

lend 0x6b2cD9F0Eb10E377c718753575B319D8C38Ad33c

oracle 0x519dD028CE0c4B20ae647619487C9512A845C64A

shib 0x59f867dBb335A0E51e8ce010F0Db17eD8c2D935c

accessControlSingleton 0x5121232FA8DC5c49a9a320567813809bbCC06cB9

oracleAggregator 0x79F93C0778c53Ce9dC306cC28aa145e2379d97e2

Celo addresses (testnet)

lend 0x2a958EFb0dCd381c036675D564c08eB1909C38AC

oracle 0x97eaA69F210426eaC3A391d6d4377cfe85443494

shib 0x7a1adc8340C00AA3Ecdd4Ecf36182Eed5D1BAb0B

accessControlSingleton 0x708071C080E5ceb3cc0fb8fb4fD1034766eAef24

oracleAggregator 0xDF2e747Ae22Ea80B5f6C8f8BA8FDC2FAAC996762

Chiliz addresses (testnet)

lend 0x4274163619a3E4EA3C310a93C4B2f827F07FC5a4

oracle 0x11F9724E795Ce0CD9E0366286eA45C1BC578E984

shib 0x43bf5867544FebB4E89139b01ef15DCbC9E5A674

accessControlSingleton 0xDF2e747Ae22Ea80B5f6C8f8BA8FDC2FAAC996762

oracleAggregator 0x7a1adc8340C00AA3Ecdd4Ecf36182Eed5D1BAb0B

Scroll addresses (testnet)

lend 0x2a958EFb0dCd381c036675D564c08eB1909C38AC

oracle 0x97eaA69F210426eaC3A391d6d4377cfe85443494

shib 0x7a1adc8340C00AA3Ecdd4Ecf36182Eed5D1BAb0B

accessControlSingleton 0x708071C080E5ceb3cc0fb8fb4fD1034766eAef24

oracleAggregator 0xDF2e747Ae22Ea80B5f6C8f8BA8FDC2FAAC996762

Mantle addresses (testnet)

lend 0x2a958EFb0dCd381c036675D564c08eB1909C38AC

oracle 0x97eaA69F210426eaC3A391d6d4377cfe85443494

shib 0x7a1adc8340C00AA3Ecdd4Ecf36182Eed5D1BAb0B

accessControlSingleton 0x708071C080E5ceb3cc0fb8fb4fD1034766eAef24

oracleAggregator 0xDF2e747Ae22Ea80B5f6C8f8BA8FDC2FAAC996762

Base addresses

lend 0x2a958EFb0dCd381c036675D564c08eB1909C38AC

oracle 0x97eaA69F210426eaC3A391d6d4377cfe85443494

shib 0x7a1adc8340C00AA3Ecdd4Ecf36182Eed5D1BAb0B

accessControlSingleton 0x708071C080E5ceb3cc0fb8fb4fD1034766eAef24

oracleAggregator 0xDF2e747Ae22Ea80B5f6C8f8BA8FDC2FAAC996762

Developer Feedback

Chronicle:

• Can’t find any example of oracle usage. For example what changed if we want to use Chronicle instead of Chainlink.
• Not clear why we need to whitelist address to be able to call latestRoundData
• It will be helpful to test if there was also all contract addresses on mainnet (not only Sepolia)
• At first it was not so clear what is oracle and what is feed
• Cool, that there is a good usage as Chainlink

Neon:

• https://proxy.devnet.neonlabs.org/solana returns HeadersTimeoutError: Headers Timeout Error
• https://devnet.neonevm.org RPC returns:
  • Error HH110: Invalid JSON-RPC response received: <title>502 Bad Gateway</title>
• Cool faucet
• Contract verification isn't supported by default by hardhat

Base:

• Very slow deploy on testnet. As in another chains we don't set gas, but 10 minutes after starting deploy it happens nothing
• Mainnet deploy work fast
• Faucet for Base Goerly didn't work, so we need to use Base Sepolia
• Contract verification isn't supported by default by hardhat

Mantle

• Only faucet with bridge works for me (https://faucet.testnet.mantle.xyz/), it's complex, but the bridge works fast, that was very good
• Contract verification isn't supported by default by hardhat

Celo

• Great faucet
• It's bad that there is no injected in hardhat verifier, but it's cool that there is hardhat-celo. Not many chain do that.

PolygonZK

• Mainnet works fast
• Comfortable native bridge
• It'll be nice if I can natively bridge matic from polygon to eth to polygonZK
• Contract verification isn't supported by default by hardhat

Chiliz

• Faucet: Not clear why we need to create a tweet, why not to do like in another faucets - x CHZ is free, if we only connect github/Alchemy/twitter => we get (n * x) CHZ
• But it's good that there is a lot of mocked tokens available in testnet faucet
• Deploy works fast
• Contract verification isn't supported by default by hardhat

Arbitrum

• Only tried on mainnet, but it works perfect and fast
• It's very good that there is hardhat verification with Arbitrum mainnet and testnet

The product

Meowlend: Dive into high-risk, high reward crypto lending with Meowlend. Enjoy high APRs on deposits & easy 1-click borrowing. User-friendly interface for hassle-free loans & repayments. Isolated Risk for each memecoin.

Lending Protocol Specification

Overview

The lending protocol facilitates two main activities for users:

1. Deposit and Earn Interest: Users can deposit a specific ERC20 token into the pool to earn interest.
2. Borrow Against Collateral: Users can deposit ETH as collateral to borrow the ERC20 tokens.

Key Components

ERC20 Token Pool

• Users deposit ERC20 tokens into the pool.
• Depositors earn interest based on pool utilization.

ETH Collateral

• Users deposit ETH as collateral to borrow ERC20 tokens.
• The amount that can be borrowed is dependent on the Loan-to-Value (LTV) ratio.

Interest Rate Calculation

• Interest rates for borrowers are determined based on the pool utilization rate.
• Higher utilization leads to higher interest rates.

Loan and Repayment

• Users borrow ERC20 tokens against their ETH collateral.
• The borrowed amount of ERC20 tokens remains constant; however, the ETH collateral returned upon repayment will be less, accounting for the interest paid in ETH.
• Borrowers must maintain a minimum loan size to ensure the viability of the liquidation process (covering gas costs).

Liquidation Process and Incentives

• In the event of under-collateralization, the loan becomes eligible for liquidation.
• The protocol uses the ETH collateral to purchase ERC20 tokens via Uniswap to cover the debt.
• A portion of the ETH collateral (a small percentage) is awarded to the caller of the liquidation function as an incentive to cover their transaction (gas) costs.

Functionalities

depositTokens(tokenAmount)

• Allows users to deposit ERC20 tokens into the pool.
• Updates the user's deposit balance and total token deposits in the pool.

withdrawTokens(tokenAmount)

• Allows users to withdraw their deposited ERC20 tokens along with accrued interest.

depositCollateral() (payable)

• Users deposit ETH as collateral.
• The amount of ETH deposited is tracked as the user's collateral balance.

borrowToken(tokenAmount)

• Users can borrow ERC20 tokens against their ETH collateral, subject to a minimum loan size to ensure the liquidation process is gas cost-effective.
• Checks the LTV ratio to determine the maximum and minimum borrowable amounts.

repayLoanAndWithdraw(tokenAmount)

• Users repay the borrowed ERC20 tokens.
• The interest for the loan is paid in ETH, and the remaining ETH collateral (minus interest) is returned to the user.

liquidateLoan(borrower)

• Can be called on under-collateralized loans.
• Converts the borrower's ETH collateral into ERC20 tokens via Uniswap to cover the debt.
• Awards a percentage of the ETH collateral to the liquidator to cover gas costs.

Additional Considerations

• Security Measures: Implement reentrancy guards and other security best practices.
• Dynamic Interest Rates: The interest rate model should be robust to handle rapid changes in market conditions.
• Uniswap Price Feeds: May require integration with oracle services for accurate ETH to ERC20 conversion rates.
• Regulatory Compliance: Be aware of legal and regulatory requirements in jurisdictions where the protocol operates.