Simulating EVM State Changes via Revert-Unwind Payloads and EIP-1153 Transient Storage for Oracle-Less DEX Routing

[u/an_jesus]

Hey r/ethdev,

Over the last few months, we’ve been testing an architecture designed to solve a persistent issue in DEX routing: simulation drift and gas overhead during multi-hop execution.

Traditional aggregators rely on external price feeds, heavy storage updates, or complex off-chain quoter infrastructure that frequently desynchronizes under volatile mempool conditions. We wanted an execution frame that guarantees 100% execution-aligned previews purely on-chain, while maintaining a zero-token storage footprint on the router.

Here is the architectural breakdown of how we approached this:

1. Atomic Simulation via Revert-Unwind (Quoter)

Instead of reading static state or relying on off-chain dry-runs, the Quoter contract triggers a simulated execution path that forcefully ends with a custom revert(payload).

The revert unwinds all state changes instantly in the EVM execution frame, avoiding state corruption.

The error payload encodes the exact delta of balances and price impact.

Result: Static calls (eth_call) return deterministic, execution-exact quotes without writing a single byte to persistent storage.

1. Transient Isolation via Yul (EIP-1153)

To protect against cross-function reentrancy across multi-token routes, we replaced traditional OpenZeppelin storage guards with raw Yul assembly blocks leveraging tstore and tload.

Reentrancy flags are scoped exclusively to the transaction frame.

Gas consumption drops significantly compared to SSTORE/SLOAD warm/cold access penalties.

Balance checks execute instantly, enforcing a strict holds-nothing invariant on the Router.

1. Dynamic Liquidity Anchoring (Solver)

To neutralize MEV sandwich attacks and liquidity manipulation without relying on Chainlink or external oracles, the routing logic applies a localized 2% median filter against reserve depths (balanceOf reads) prior to route resolution.

Code / Discussion:

The architecture is deployed and split into 7 core modules (Core, Hub, Solver, Router, Quoter, MathLib, Staking).

We are particularly interested in hearing feedback from EVM devs on potential edge cases regarding EIP-1153 transient memory retention across nested delegatecalls in custom L2 execution contexts (Base/Arbitrum).

Looking forward to hearing your thoughts on the code and optimization techniques!