Optimism tests stake-based gas priority on OP mainnet

Optimism’s OP mainnet has begun a four-week experiment that lets users boost transaction priority by staking at least 100,000 OP, marking the first time its sequencer has deviated from pure gas-fee ordering.

According to an official announcement from Optimism, OP mainnet has “adjusted its transaction sorting rules for the first time,” adding an experimental stake‑based priority track to the long‑standing “highest priority gas fee first” mechanism that currently governs the network’s sequencer. OP users can now voluntarily participate in a four‑week pilot, running through June 23, by staking no less than 100,000 OP into the new PolicyEngine Staking contract.

The goal, as outlined in Optimism governance discussions, is to test whether stake‑based ordering can dampen toxic arbitrage traffic, create new demand for OP, and give sophisticated users a more predictable way to secure blockspace during volatile periods. For now, the experiment runs in parallel to the existing priority gas auction (PGA), and transaction ordering for non‑participants remains unchanged, preserving standard fee‑based competition for block inclusion.

Two-phase design: FIFO to stake‑weighted gas

The pilot is structured in two distinct phases, each probing a different piece of the ordering puzzle. In phase one, covering the first week, all participating addresses that meet the 100,000 OP threshold are treated equally under a strict first‑in, first‑out (FIFO) rule, meaning that “exceeding the minimum staking amount will not affect priority,” according to Optimism’s description of the rollout.

From weeks two through four, the mechanism shifts to a “priority gas multiplier” that is explicitly “weighted by staking duration,” so that the longer an address has locked its OP in the PolicyEngine contract, the higher its effective gas‑priority weight becomes when competing for ordering. In practice, this gives long‑term stakers an edge in securing inclusion for latency‑sensitive flows such as arbitrage, liquidations or high‑frequency trading strategies, a design that resembles the way some exchanges reward resting liquidity over opportunistic takers.

Crucially, the rest of the network stays on the familiar rails. Users who do not opt into the experiment continue to be ordered solely by the PGA system that OP mainnet has used “for many years,” with no change in how standard wallet transactions compete on gas price alone. That parallel track helps isolate the behavioral impact of the new staking queue while reducing the risk that a flawed design could disrupt day‑to‑day activity on one of Ethereum’s most used layer‑2s.

Broader L2 and staking context

The Optimism pilot lands at a moment when Ethereum layer‑2s are experimenting aggressively with new ways to price and allocate blockspace, from shared sequencer proposals to intent‑based architectures and order‑flow auctions. Similar to how liquid staking protocols such as Lido Finance have used incentives to pull staked assets onto networks like Optimism and Arbitrum, OP’s PolicyEngine design explicitly tries to turn governance tokens into a lever for transaction priority rather than just voting power or emissions farming.

The OP ecosystem has also been positioning itself as a core venue for both DeFi and speculative flows, vying with other layer‑2 and sidechain environments that pitch lower fees or specialized features. That competition has helped drive experimentation across the stack, from token economics to sequencer design, and echoes earlier phases of infrastructure innovation that saw protocols from Bitcoin to Ethereum re‑think everything from fee markets to MEV capture.