La Cartera
"La Cartera" is a smart contract wallet that makes sending and receiving pesos (and other crypto) in Mexico, as easy as a SPEI (Bank ACH transfer equivalent).
Project Description
"LaCartera" app creates a smart contract wallet that is capable of handling gasless transactions to transfer the token $XOC and integrates easy on-ramp.
Demo of gasless transaction to pay Ethereum México Travel Expenses Scholarship: https://www.loom.com/share/4f83af2d45b7496dacc1728aa7fab657?sid=bc1e316a-eaca-4dd9-95d0-b840210e4ae2
$XOC is a decentralized stablecoin currently on Polygon (POS) with soft peg to the Mexican peso integrated to the second most used on-off ramp in Mexico called Suarmi.
The goal is to make transferring, and receiving pesos (or XOC) in crypto as easy as current web2 base fintech banks in Mexico.
The gasless transactions currently are configured to only allow transfers of $XOC, but it could be extended to allow usage with other DeFi applications without the need to have MATIC the native token.
The keys of the smart contract wallet can be generated through the Privy authorization kit which allows the user to create MPC keys utilizing regular web2 social logins as an option instead. Optionally, a user who is already savy with private keys could decide to handle their smart contract wallet with their existing preferred key(s) / wallet(s).
We tested "LaCartera" during Ethereum México, sending small $XOC amounts to different people and checking their new $XOC balances. After a few small tests, we were able to pay a scholarship for an assistant for 1000 $XOC (which is $1000 pesos), using gasless transactions, to help with travel expenses.
In summary we want "La Cartera" to make onboarding to Web3 in Mexico as simple as possible to all users without giving the burden of worrying about native gas, and or private key management.
How it's Made
Our first objective is to simplify private key management for the user. To achieve this, we've seamlessly integrated the auth-kit from Privy. Privy is a service that enables users without a private key to create an MPC wallet using their existing web2 social logins. Optionally, Privy also offers users with existing wallets the ability to use them for authorization.
The subsequent step involved creating a smart contract wallet. Due to the proven track record of the (Gnosis) Safe protocol, we opted to implement this through the Safe Protocol Kit SDK, which we use to deploy a proxy Safe contract.
Within our app, we retrieve the linked Safe contract associated with a wallet using the Safe API Service.
Once a user has a Safe wallet, we facilitate gasless transactions with the "La Cartera" native wallet using the Relayer Kit from Safe.
Our front-end is a PWA built using Next, and we use several web3 technologies such as Wagmi, Viem and Safe Core Kit. ChakraUI was used for components.
