safeSchnorr Schnorr signatures come with big potential but limited support in the Ethereum ecosystem. Here's a reminder of the advantages they have in a multisignature setup: one EVM address signer - even if your multisig is composed of 10 signers, on-chain that is represented by a single EVM address. You get privacy as on-chain nobody knows who the real signers are gas efficiency - all the signatures are aggregated into one off-chain, allowing the user to send the final, aggregated one on-chain. Verification is handled by ecrecover (~3000 gas) + a bit of math computation beforehand, bringing the total gas cost to ~3300 gas. Nevertheless, they are not so popular and probably the main reason for this is the lack of hardware support and the difficult off-chain setup you need to handle them. Here, I'll demonstrate how to enable and use these schnorr signatures as a Safe module. Here' the github repository

ERC-4337 represents an array of challenges, some of which are present or not depending on the initial design decisions you decide to go with. For example: Should we deploy the SA (smart account, the official term for a smart contract wallet) the moment the user's address is calculated or later Should we sponsor the deployment or ask the user to pay it How do we give permissions to the EntryPoint to execute transactions And the list goes on. As a developer, I feel nothing but excitement for the freedom a wallet has in making its own design decisions and tackling them along the way. So, to understand what the challenge is and how we tackled it, the starting point is understanding the decisions we've made for our wallet. And we should start with a couple of main points:

Abstract Multi-signatures are one of the most powerful constructs in Web3. Other than enabling DAOs and corporate treasuries, they also serve to improve personal security in the form of multi-factor authentication, for example signing a transaction on your laptop and mobile phone, which with modern secure enclaves can rival hardware wallets in terms of security, if not surpass them. Historically there have been multiple ways to implement multi-signatures, from the naive on-chain multisig code, like Gnosis Safe, to multi-party computation on ECDSA. However, there is a way to do it that is cheap to verify on-chain, easy to implement, and extremely flexible: Schnorr signatures. We propose a JS library that can construct Schnorr aggregate signatures that can be verified on-chain for the cost of a regular ecrecover. Currently, the library is in prototype stage. Why Schnorr signatures + account abstraction is a powerful combo