Polygon suffers hour-long outage weeks after complex hard fork

Polygon went dark for over an hour on Wednesday after a validator left the network, triggering an unexpected bug. The protocol is live now that developers found a patch.

According to the Polygon Foundation, there was a “temporary disruption” to Polygon’s Heimdall system used to run validators, maintain consensus, and link to the Ethereum mainchain. Heimdall, named after a prominent god in Norse mythology, is one of the two primary layers of the Polygon PoS network, alongside Bor, which produces blocks.

“Approximately 4 hours ago, Heimdall experienced a temporary disruption that led to a one-hour halt in chain progression, caused by a validator exit,” the foundation said. “Bor remained fully operational throughout, continuing to produce blocks without interruption.”

Notably, the consensus bug comes just weeks after Heimdall was upgraded to CometBFT and Cosmos SDK v0.50 to reduce finality times and improve scalability on July 10. Polygon has referred to the Heimdall v2 update as its “most technically complex” hard fork since 2020.

Polygon is one of the largest and most influential Ethereum Layer 2s with over $1.1 billion in total value locked. Once dominant, the network has been losing influence amid a growing field of L2 competition. POL is trading at $0.22, down about 1% on the day, according to The Block’s data page.

The largest blockchain-based prediction market, Polymarket, is primarily housed on Polygon. An error warning on Polymarket’s website briefly showed that the market was experiencing errors.

Polygon’s error site shows that the bug was detected shortly before 10:00 am ET and resolved at 11:01 am ET. Polygon said the network’s block-producing Bor layer remained unaffected, suggesting regular transactions on the Polygon network continued without interruption.

“To be clear: the Polygon PoS chain has remained live, but due to RPC issues, users may experience disruptions accessing various apps,” the foundation said. “We are now actively collaborating with RPC providers to accelerate resolution and restore user-facing services.”

The network is not the only to suffer outages. On Tuesday, Hyperliquid suffered an API outage reportedly caused by a “spike in traffic.” It’s also not the first time Polygon has gone down.