Optimism Superchain Upgrade Clears Path for Interoperability

The Optimism network has completed voting on an upgrade that will enable its Superchain to eventually become interoperable. The Upgrade 20, approved by Optimism's governance on September 16, moves its fault-proof system closer to the architecture required for future cross-chain interactions.

The update shifts the way chains challenge incorrect state before withdrawals are finalized back to Ethereum, using timestamps instead of Output Root Dispute Games. This change is seen as a prerequisite for interoperability because it will eventually allow Super Roots to represent multiple chains at the same timestamp.

Mainnet execution of the upgrade is scheduled for September 24, if the new system completes a healthy seven-day testnet soak. The release also includes changes to Optimism's contracts manager and SystemConfig, including safeguards around upgrade sequencing and cleanup of legacy configuration functions following issues identified during Upgrade 19.