4337-7702 Migration

For years, the dominant path to account abstraction in Ethereum was ERC-4337. It allowed smart contract wallets to operate via off-chain bundlers, paymasters, and a middleware layer (EntryPoint) without needing to change the core protocol. But it comes with complexity: dependency on bundlers, higher gas overhead, coordination with paymaster infrastructure, and friction for atomic multi-step or cross-chain flows.

Sail chose to migrate to ERC-7702 / EIP-7702 because it unlocks a cleaner, more native abstraction that aligns better with what we want: autonomous, non-custodial swaps & bridges without breaking the model of user-owned accounts.

What ERC-7702 Enables

• Delegated execution at transaction level 7702 introduces a new transaction type where an Externally Owned Account (EOA) can include a contract_code or authorization_list that temporarily delegates execution to smart contract logic within that transaction, without permanently converting the account.

• Native atomic execution Because 7702 brings execution of contract logic into the transaction itself, agents can bundle cross-step actions (swaps, bridging, reallocations) atomically, reducing risk from partial execution or MEV exposure.

• Cross-chain delegations The authorization in 7702 can include chain identifiers, allowing code delegation across specific chains. That means the same account can be functional across networks (when the agent is allowed) without requiring multiple addresses or forks.

• Gas sponsorship / abstraction 7702 supports scenarios where transactions can be sponsored — for example, a protocol or agent covering gas — because the logic is internal to the transaction. Circle, for instance, highlights that 7702 will enable gasless USDC transactions without requiring smart contract deployment.

• Simplified infrastructure Without needing bundlers and paymasters for every move, the execution layer becomes leaner and lower-latency. The fewer moving pieces, the fewer points of failure or contention.

Why This Matters for Non-Custodial Swaps & Bridges

Because Sail’s agents must move funds across chains and assets without ever giving up custody, 7702 is a foundational enabler:

1. No fund transfer to third-party contracts Under 7702, the account itself is capable of executing the logic, so we don’t need to wrap user funds into a central contract that then routes them.

2. Atomic safety Swap + bridge + reallocation can all happen in one transaction (or fail fully) — critical for user safety and trust.

3. Permissioned autonomy Using session keys and delegated logic with 7702, agents can operate automatically but within safe limits (e.g. maximum slippage, allowed routes).

4. Lower friction, better UX Users don’t need to think about deploying contracts, migrating addresses, or complex gas flows. Everything can feel like a native wallet action, even across chains.

By migrating to 7702, Sail becomes one of the first systems capable of autonomous, non-custodial cross-chain reallocation — truly letting money move itself under guardrails.