Optimism collaborates with Flashbots to enhance sequencing capabilities on OP Stack

August 21, 2025 Adam Forsyth

Key Takeaways

Optimism and Flashbots have partnered to deliver advanced sequencing tools for the OP Stack, enabling chain differentiation and faster scaling.
The Superchain, representing over 60% of Ethereum layer 2 activity, will benefit from features like 200ms confirmations and programmable block building.

Optimism has teamed up with Flashbots to enhance sequencing capabilities across the OP Stack, providing builders with tools for chain differentiation, value capture, and faster scaling, the companies announced Thursday.

Optimism is partnering with Flashbots to bring fast, verifiable sequencing to the Superchain 🔴

Faster confirmations = smoother user experience. pic.twitter.com/85NQQGSVBe

— Optimism (@Optimism) August 21, 2025

The Superchain, which comprises networks like Base, Unichain, World Chain, Ink, and Soneium, currently accounts for more than 60% of all Ethereum layer 2 activity as of August 2025.

The collaboration with Flashbots, the R&D group behind MEV-Boost, BuilderNet, and Flashblocks, is expected to take the stack’s performance and flexibility to a new level.

Through this partnership, OP Stack builders will gain access to a suite of sequencing features that have been battle-tested on Ethereum and refined for layer 2 environments, including 200ms confirmations through Flashblocks, which is already operational on Base and Unichain and will soon expand to OP Mainnet and other Superchain chains.

Other features include programmable block building, verifiable fairness using secure enclaves, responsible MEV capture, and enhanced spam resistance.

These capabilities enable builders to customize latency, fairness, and scalability for specific use cases, retain sequencer revenues within their ecosystem, and accelerate time-to-market with proven components.

“With Flashbots as a core technology partner, we’re accelerating the roadmap for fast, cheap, and customizable sequencing across the OP Stack,” said Sam McIngvale, Head of Product at OP Labs. “This is part of our broader mission: giving builders the freedom to design their chains their way, with infrastructure that’s open, flexible, and battle-tested in production.”

The partnership will focus on expanding Flashblocks across the Superchain while implementing advanced sequencing options as configurable features.