Optimism Taps Flashbots to Supercharge OP Stack Sequencing

Optimism is teaming up with Flashbots to revamp how transactions get processed across its OP Stack ecosystem, aiming to make some of Ethereum’s most popular layer-2 networks faster and more customizable.

The partnership centers on sequencing, the behind-the-scenes process that determines how quickly a transaction confirms, which trades are prioritized, and how much users ultimately pay. Optimism says Flashbots’ infrastructure, which is already responsible for building more than 90% of Ethereum’s blocks, will now bring near-instant confirmations and user-friendly transaction ordering to every chain in the so-called Superchain.

This matters because the OP Stack underpins more than 60% of all Ethereum layer 2 activity, the Optimism team claims, including some of the most well-known layer-2 chains like Base, Unichain, World Chain, Ink and Soneium. Until now, advanced sequencing features such as ultra-fast settlement, frontrunning protection and custom compliance rules were only available to the largest chains with resources to build them in-house. With Flashbots on board, those features will be available via tools for any project building on Optimism’s OP stack.

Flashbots is best known for its work on MEV, or maximal extractable value, where its MEV-Boost tool has reshaped how blocks are produced.

Some of Flashbots’ sequencing technology is already live on OP Stack chains: Base and Unichain use “Flashblocks” to deliver block times as low as 200 milliseconds, while Unichain and World Chain are experimenting with verifiable transaction ordering and priority blockspace, which proves transactions are ordered fairly and prevents frontrunning.

In the coming months, Optimism and Flashbots plan to roll out the flashblocks and advanced sequencing R&D to Optimism’s mainnet and other chains using the OP Stack.

“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.”

Read more: Optimism’s Jing Wang and the Widely Adopted OP Stack