Base Goes Stale for Two Hours, Comes Back Fresh-Faced Just in Time for Beryl 🚧

Base, the Coinbase-incubated Ethereum layer-2 network, resolved a roughly two-hour outage on Thursday that halted block production on mainnet, with the Base engineering team later identifying a sequencer bug as the root cause in a Saturday post-mortem. The network first posted to X around 12:20 p.m. ET on Thursday that "Base Mainnet is currently halted while the team works on an issue with block production," adding that "all funds are secure, and we'll update below once resolved."

According to Base's status page, the team at 5:21 p.m. UTC said it "isolated a consensus problem that caused an invalid block to be sequenced. This prevented new blocks from being created." By just before 6 p.m. UTC, the network reported it had "recovered healthy blockbuilding" and that ecosystem-wide infrastructure was syncing. The post-mortem stated that the first incident lasted 116 minutes and a second outage the following day lasted 20 minutes, both involving a complete halt of new layer-2 blocks while sequencer and validator nodes could not progress past the invalid block.

The post-mortem said a sequencer block-building logic bug allowed "stale journal state" to persist after a transaction validation failure: "An invalid transaction was received by the block builder and failed during execution, as expected, but erroneously did not clear the journal state that contained the accounts and storage slots that had been accessed." The team applied a patch to ensure the journal state was properly updated during execution, noting that mitigation took longer than expected "due to infrastructure conditions unrelated to the original bug," and that a subsequent "race condition" after the system reset caused the second outage.

Base creator Jesse Pollak wrote on X that "All funds are/were safe. But a halt is not okay, and we'll use this to continue to level up Base as a platform for global, 24/7 finance." The network said it plans to improve protocol "fuzz testing" and build "graceful recovery" so validator nodes do not require manual restarts during future incidents. Base runs a single sequencer, a centralized component that determines transaction order and has been responsible for prior outages on layer-2 chains including Arbitrum, OP Mainnet and zkSync Era.

The Thursday downtime occurred hours before Base's scheduled Beryl hardfork upgrade at 6 p.m. UTC, which was completed two hours later at 8 p.m. UTC and introduced a new token standard for stablecoins and tokenized real-world assets while aiming to reduce withdrawal delays. Base previously experienced a 17-minute block production halt in September 2024 and a roughly 33-minute outage in August 2025, and reported around 30 hours of withdrawal delays in May. Base is the second-largest layer-2 network by total value secured at just under $11 billion, according to L2beat.