OP Labs

Welcome to Optimism, Akosh! Akosh Farkash is joining as a Senior Software Engineer with over six years of blockchain experience, including at Aztec, Matter Labs, and Protocol Labs. He’s a full stack engineer who’s been programming since 2004. Excited to have you onboard.

Upgrade 20 is here. The OP Stack fault proof system is getting ready for interoperability. This upgrade lays the groundwork for all OP chains to interact as one. The key upgrade: U20 replaces each chain's output root with a super root, a timestamp-based commitment built to

Article Upgrade 20: Preparing the Fault Proof System for Interop Upgrade 20 delivers a major upgrade to the OP Stack fault proof system to lay the groundwork for supporting interop. Proposals move from the single-chain output roots to the multi-chain capable super

Subblocks go live on OP Sepolia Monday, Aug 17. Preconfirmations move from 250ms to 200ms. Four payload fields are set to their zero value: - state_root - block_hash - withdrawals_root - withdrawals to their zero value For teams consuming the subblock stream directly: - Optimism Documentation From docs.optimism.io

Upgrade 19, the Karst hard fork, is scheduled to activate on Mainnet OP Stack chains Wed, Jul 8, 2026 at 16:00:01 UTC. Please refer to the notice page for full details and required actions. Optimism Documentation From docs.optimism.io