Overview
- Base’s sequencer, operated by Coinbase, stopped producing blocks on June 25, 2026 after an invalid/problematic block caused a consensus failure and froze transaction processing for roughly two hours.
- Engineers identified and isolated the problematic block, restarted sequencing, and said internal nodes were syncing while ecosystem node operators were advised to restart to recover service.
- Lead builder Jesse Pollak and official status updates repeatedly confirmed that user funds were secure throughout the outage and that the team is still investigating the root cause.
- The halt came hours before Base’s scheduled Beryl upgrade but the team has not confirmed any link to the upgrade, and the network has not yet published a full post-incident report.
- The incident highlights the ongoing risk from Base’s single, Coinbase-run sequencer and adds pressure for decentralization work such as Appchains, the Reth migration and other resilience efforts that have not yet removed the single-point-of-failure.