What if EOAs could get the powers of Smart Accounts?! Now it's possible with: Fusion Module Bringing SA capabilities to EOAs such as ⛓️Chain Abstraction ⛽Gasless Transactions 📦Transaction Batching 🤖Automated Transactions Let's do a deep dive into how it works🧵👇

The best part? The Fusion Module can be implemented right away — no need to wait for the 7702 Pectra protocol upgrade, while remaining fully compatible when it goes live. Our in-depth deep dive is now live on ETH Research: For a quick primer, read on👇

Our innovation enables the virtual merging of EOA and SCA into a single entity. Without requiring users to upgrade their EOA or manually transfer funds to a new SCA address Thus, eliminating one of the biggest friction points hindering SCA adoption!

The idea is to attach an ERC4337 "companion account" to the user’s EOA This companion account is invisible to the user - they continue using the EOA as their primary wallet. While the companion SCA handles all instructions (UserOps) with a single singature!

That's where the Fusion magic lies! User signs just once to - 1. Transfer tokens to the companion Smart Contract Account and 2. Provide the bundlers with the necessary instructions (UserOps) for their intent / desired action

Thus, Fusion Module provides a full EOA-like experience to the user while utilising funds from their EOA as if they were directly using the smart account! Bringing Smart Account capabilities to an EOA, without any changes to a normal EOA user's behaviour!

To implement this, we leverage the fact that arbitrary data can be appended to the callData field of an EVM transaction, while still keeping the transaction valid. This data can be the UserOp(s) hash to be executed by bundlers. Read more:

The user's signature covers the entire transaction, including all appended extra data. Achieveing both actions simultaneously with a single signature, for e.g. 1. Transfer 100 $USDC to the companion SCA on Base 2. Extra data (UserOps) to bridge it to Optimism & swap to $OP

The key requirement for this to function is that the user's companion SCA contains a module capable of verifying the userOp(s) in this appended data of the signed & serialized EVM transactions That's what the Fusion modules does, which we have developed!

Once the Fusion module has done the verification, the userOp(s) can be executed by any entity willing to pay for gas costs. But collecting this gas fee back from the user is a separate headache, as the current 4337 infrastructure can't handle it. That's where MEE comes in!

The MEE (Modular Execution Environment) stack supports diverse gas payment models, including scenarios where Fusion Module manages EOA assets through companion SCA. Dive deeper into how Fusion Modules act as first-class citizens within the MEE stack:

MEE uses supertransactions instead of standard transactions. Each supertransaction, identified by a single hash, can bundle multiple userOps. This aligns perfectly with Fusion Modules, enabling users to execute complex interactions by signing one root hash.

Thus, the Fusion Module enable users to use their EOA like a Smart Account, without knowing about the SCA's existence! They can execute multi-step actions, directly approving & spending funds from their EOA, while the companion SCA handles the execution behind the scenes.

The Fusion module is fully compatible with major wallets such as @MetaMask, @Rabby_io & @TrustWallet! Ready to enable smart contract capabilities on the EOA for your dapp or wallet? Reach out here: