ERC7399 Flash Lender Wrappers

This repository contains contracts that work as ERC7399 entry points for popular flash lenders.

How Do These Wrappers Work

sequenceDiagram
  title ERC3156Wrapper
    Borrower->>Wrapper: ERC7399.flash(to,token,amt,data,callback)
    Wrapper->>Lender: lender specific flashLoan call
    Lender-->>Wrapper: transfer loan amount
    Lender->>Wrapper: lender specific callback()
    Wrapper -->>Wrapper: bridgeToCallback()
    Wrapper-->>Borrower: transfer loan amount
    Wrapper->>Borrower: callback()
    Borrower -> Borrower: Borrower does stuff
    Borrower -->> Wrapper: transfer loan amount + fee †
    Borrower ->> Wrapper: callback return
    Wrapper --> Wrapper: approves token repayment to lender †
    Wrapper -->> Lender: lender calls transferFrom(wrapper, amount + fee) †

Loading

† For the BalancerWrapper and Uniswap v3 the borrower transfers the repayment to the lender and the wrapper skips the repayment approval.

Deployments

Lender	Address	Networks	Gas	Fees	Contract
Aave v2			262190	0.05%	AaveWrapper
Aave v3	0x9D4D2C08b29A2Db1c614483cd8971734BFDCC9F2	Arbitrum One, Optimism, Polygon	212569	0.05%	AaveWrapper
Aave v3 (Permissioned)	0x0c86c636ed5593705b5675d370c831972C787841	Ethereum, Gnosis	229742	0	AaveWrapper
Aerodrome	0x69b6E55f00d908018E2D745c524995bc231D762b	Base	163919	Variable	SolidlyWrapper
Balancer v2	0x9E092cb431e5F1aa70e47e052773711d2Ba4917E	Ethereum, Arbitrum One, Optimism, Polygon, Gnosis	113032	0	BalancerWrapper
Balancer v2	0xD534400B0555F8441c5a3e0E9e585615B54fB2F4	Base	113032	0	BalancerWrapper
Balancer + Compound v2			836719	0	CompoundWrapper
Balancer + Moonwell	0x6207ec38da68902CC60D3760c9fe3EB64B426207	Base	1183309	0	CompoundWrapper
Balancer + Pendle	0xC1Ea6a6df39D991006b39706db7C51f5A1819da7	Arbitrum One	525422	0	BalancerPendleWrapper
Balancer + Silo	0x0F9104Fec1a5C91e63632E215e8F5c57C8f32c77	Arbitrum One	1025824	1	SiloWrapper
Balancer + Silo	0xAa8F3BF0C9e1aD581547D9803066084E57907a33	Optimism	1025824	1	SiloWrapper
Camelot	0x5E8820B2832aD8451f65Fa2CCe2F3Cef29016D0d	Arbitrum One	80679	0.01%	AlgebraWrapper
Camelot + Pendle	0xC9d66F655b7B35A2B4958bE2FB58E472736Bbc47	Arbitrum One	506792	0.01%	AlgebraPendleWrapper
Dolomite	0x54F1ce5E6bdf027C9a6016C9F52fC5A445b77ed6	Arbitrum One	459815	0	DolomiteWrapper
Gnosis Safe			109223	Variable	GnosisSafeWrapper
MakerDAO			313172	0	ERC3156Wrapper
MorphoBlue	0xa0Cb4e1222d813D6e4dE79f2A7A0B7759209588F	Ethereum	132114	0	MorphoBlueWrapper
MorphoBlue	0xd0953257A5a2603Bf9fCA8aF1F2ecdac60EB8F52	Base	132114	0	MorphoBlueWrapper
MorphoBlue + Pendle	0xE1f9e06006B2592dDe5b1bBA3ae2DD34DF557007	Ethereum	558536	0	MorphoPendleWrapper
Spark	0x8cB701df93f2Dae295aE8D7beE5Aa7e4D40CB397	Ethereum, Gnosis	212569	0	AaveWrapper
Uniswap v3	0x319300462C37AD2D4f26B584C2b67De51F51f289	Arbitrum One, Polygon, Ethereum	94720	Variable	UniswapV3Wrapper
Uniswap v3	0xfFD51f0631E79c39646A09318B2E18432E788B75	Optimism	94720	Variable	UniswapV3Wrapper
Canonical	0x6962ba38D6493B9Ed7E0a4b74624c43D844E1438	Optimism	94720	Variable	UniswapV3Wrapper
Uniswap v3 + Pendle	0xa353Fd50210786F0E038ddD574A21d0CCefb3163	Arbitrum One	497567	Variable	UniswapV3PendleWrapper
Velodrome	0xcF13CDdbA3aEf757c52466deC310F221e06238d6	Optimism	163919	Variable	SolidlyWrapper
ZeroLend	0xA48Cc0e4159C51d73B42c824f1444D1C1cbdA531	Ethereum, Linea	212569	Variable	AaveWrapper
ZeroLendBTC	0xB21a09be03Ce5318b3f3089665D917aFfA0aeA90	Ethereum	212569	Variable	AaveWrapper
ERC3156 (DAI, GHO, FlashMint)	0x255bAFe2122722FC35E33cd503f4f0E722AB98fC	Ethereum	279102	Variable	AaveWrapper

Disclaimer: The gas costs are calculated for calling flashLoan on each wrapper for an arbitrarily chosen token and loan amount. Gas refunds are not taken into account and might be significant in some cases. Calling the underlying flash lender directly may have larger gas savings in some instances than others. Requesting loans for different tokens or amounts might have different gas costs. For AMMs the fees often vary according to pool parameters and state.

Gnosis Safe Wrapper

The Gnosis Safe Wrapper is intended for individual users to flash lend their own assets held in a Gnosis Safe and earn a fee. To enable it, from your own Gnosis Safe, execute a transaction bundle to enable the GnosisSafeWrapperFactory and set the fees for individual assets.

safe.enableModule(gnosisSafeWrapperFactory);
gnosisSafeWrapperFactory.lend(asset, fee);
...

or an override to lend all assets in the safe:

safe.enableModule(gnosisSafeWrapperFactory);
gnosisSafeWrapperFactory.lendAll(fee);
...

The fee parameter can be zero for free flash loans. To disable lending, execute from your safe the following command:

gnosisSafeWrapperFactory.disableLend(asset);
...

If you set a lending override, you can disable it to go back to individual asset configuration:

gnosisSafeWrapperFactory.disableLendAll();
...

Gnosis Safe Wrapper

The Gnosis Safe Wrapper is intended for individual users to flash lend their own assets held in a Gnosis Safe and earn a fee. To enable it, from your own Gnosis Safe, execute a transaction bundle to enable the GnosisSafeWrapperFactory and set the fees for individual assets.

safe.enableModule(gnosisSafeWrapperFactory);
gnosisSafeWrapperFactory.lend(asset, fee);
...

or an override to lend all assets in the safe:

safe.enableModule(gnosisSafeWrapperFactory);
gnosisSafeWrapperFactory.lendAll(fee);
...

The fee parameter can be zero for free flash loans. To disable lending, execute from your safe the following command:

gnosisSafeWrapperFactory.disableLend(asset);
...

If you set a lending override, you can disable it to go back to individual asset configuration:

gnosisSafeWrapperFactory.disableLendAll();
...

Flash Loans

For detail on executing flash loans, please refer to the ERC7399 EIP.

Safety

This is experimental software and is provided on an "as is" and "as available" basis.

While care has been taken during development, and most contracts have seen significant use, we do not give any warranties and will not be liable for any loss incurred through any use of this codebase.

Using This Repository

This is a list of the most frequently needed commands.

Build

Build the contracts:

$ forge build

Clean

Delete the build artifacts and cache directories:

$ forge clean

Compile

Compile the contracts:

$ forge build

Coverage

Get a test coverage report:

$ forge coverage

Deploy

Deploy to Anvil:

$ forge script script/Deploy.s.sol --broadcast --fork-url http://localhost:8545

For this script to work, you need to have a MNEMONIC environment variable set to a valid BIP39 mnemonic.

For instructions on how to deploy to a testnet or mainnet, check out the Solidity Scripting tutorial.

Format

Format the contracts:

$ forge fmt

Gas Usage

Get a gas report:

$ forge test --gas-report

Lint

Lint the contracts:

$ pnpm lint

Test

Run the tests:

$ forge test

Notes

1. Foundry uses git submodules to manage dependencies. For detailed instructions on working with dependencies, please refer to the guide in the book
2. You don't have to create a .env file, but filling in the environment variables may be useful when debugging and testing against a fork.

License

This project is licensed under MIT.