RoboSaver turns your Gnosis Pay card into an automated savings account!
Unused EURE on your card gets deposited into a liquidity pool, where it collects yield and swapping fees. As soon as your card's balance gets below a certain threshold, the RoboSaver will withdraw some EURE from the pool for you and top up your card. Thus creating the perfect balance between having EURE ready for spending and putting EURE to work!
Only a single smart contract is needed; RoboSaverVirtualModule. The module is "virtual", since it doesn't get installed on the Gnosis Pay Safe directly, but on the Delay module instead. This way all of its transactions still respect the necessary delay needed to eventually settle with Visa.
This PoC assumes that the safe has liquidity in the Balancer stEUR/EURE pool to begin with.
The safeTopup function exists to build the necessary calldata for the EURE withdrawal, and sends that payload to the delay module by passing it to execTransactionFromModule. After the cooldown has passed, executeNextTx can then be called (permissionlessly) on the delay module to actually execute it.
This process is then wrapped in the checker function; it either returns the payload necessary to call safeTopup or to call executeNextTx. A Gelato worker can then constantly poll checker, to know if it should top up the safe balance or execute a queued transaction.
This process can be observed to successfully work in the TopupTest.t.sol test. We were also able to successfully run this onchain:
safeTopupcall to queue up the withdrawal: https://gnosisscan.io/tx/0x97fadc58880278486e505fc9706a7cfcf5e0e0405446d0912e457bb961e65763#eventlogexecuteNextTxcall after the cooldown to actually withdraw: https://gnosisscan.io/tx/0x7852741c5b0e936703c5e0b3f69de368440ee1b1b54e2a8fd487f37fd743a68e
Note that the safe's EURE balance going below the threshold of 10 EURE triggered the Gelato worker to queue up the transaction automatically!
Roles: https://gnosisscan.io/address/0xa7882cd617b53ac5832acceec0e786dbd38fec4b#codeDelay: https://gnosisscan.io/address/0x60bea2e60ac91d354cad23391100bc24ebc9450e#codeBouncer: https://gnosisscan.io/address/0x40049dec4466fbdc52ec0c21c47c65a6315cf3e7#codeRoboSaverVirtualModule: https://gnosisscan.io/address/0xe49c90547399f592e92dd28a149a448b17cf3b2a#code
After cloning the repo, run forge build to initiate a compilation and fetch necessary dependencies.
Compilation of the contract at the end will raise some errors; this is because currently the delay-module requires a separate installation of dependencies. To fix this, run yarn install --cwd lib/delay-module.
Finally, copy .env.example to .env and populate it.
Run forge test -vvvv.