Why did Base experience two network outages?

Base experienced two outages because a bug in its sequencer block-building logic allowed stale journal state to persist after an invalid transaction failed validation. The software issue halted block production, with the first outage lasting 116 minutes and the second lasting 20 minutes.

What are sequencers on the Base layer-2 network?

Sequencers on the Base layer-2 network are responsible for ordering transactions and producing new blocks. Because Base currently operates a single sequencer, a critical fault affecting it can interrupt block production across the network.

How is Base preventing similar sequencer failures in the future?

Base said it has deployed a software patch to ensure journal state is updated correctly during transaction execution. The engineering team also plans to expand protocol fuzz testing and introduce graceful recovery mechanisms to reduce future outage risks.

What does the race condition mean for the Base network outage?

The race condition occurred after Base reset the system following the first outage and prevented sequencers from catching up. This issue caused a second outage lasting 20 minutes even after the original software bug had been addressed.

Why are the recent outages significant for Base?

The recent outages are significant because Base is the second-largest layer-2 network by total value secured and relies on a single sequencer for block production. The incidents also follow earlier sequencer-related outages in September 2024 and August 2025.

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Base identifies sequencer bug behind dual outages

Written by Isaac FrancisPublished Jun 29, 2026, 2:16 AM

Base said a bug in its sequencer block-building logic caused two network outages that disrupted block production last week.
The first outage lasted 116 minutes, while a second 20-minute outage was triggered by a race condition during system recovery.
The engineering team has deployed a patch and plans to strengthen testing and recovery processes to reduce the risk of future incidents.

Base said a bug in its sequencer block-building logic caused two separate outages on its layer-2 network last week, interrupting block production and preventing validator nodes from progressing until the issue was resolved.

According to a post-mortem published by the engineering team, an invalid transaction triggered a transaction validation failure but failed to clear a stale journal state, allowing outdated account and storage data to persist within the sequencer.

The first outage lasted 116 minutes before engineers restored block production by deploying a patch that correctly updates the journal state during transaction execution.

A second outage lasting 20 minutes occurred after the system reset because a race condition prevented sequencers from catching up, extending the recovery process beyond the initial software fix.

Base said infrastructure conditions unrelated to the original software bug also contributed to the longer-than-expected recovery time following the first incident.

The engineering team said it will expand protocol fuzz testing to better identify software faults and develop graceful recovery mechanisms that allow validator nodes to recover without requiring manual restarts.

The outages were the latest sequencer-related disruptions affecting Base, which previously experienced network interruptions in September 2024 and August 2025 and remains the second-largest layer-2 network by total value secured.