Starknet Experiences Nearly Three-Hour Outage Following Grinta Mainnet Upgrade

Ethereum Layer 2 solution Starknet announced the launch of its Grinta (v0.14.0) upgrade on its Mainnet, touting it as "a major milestone toward decentralization" and "a massive UX upgrade for everyone," according to a tweet from the official Starknet account. However, the deployment on September 2, 2025, was quickly followed by a significant network outage lasting nearly three hours, which halted transaction processing and raised concerns about the platform's stability.

The Grinta upgrade was designed to introduce several pivotal advancements aimed at enhancing the network's performance and decentralization. Key features include a decentralized sequencer architecture, implementing three independent sequencers operating with Tendermint consensus, and sub-second pre-confirmations for significantly faster transaction feedback. Additionally, the update brought a new fee market for L2 gas, inspired by Ethereum's EIP-1559, and an upgraded mempool prioritizing transactions based on tip amount.

The disruption, which lasted approximately three hours, was attributed to a sequencer failure and incompatibility with Cairo0 code. This critical issue led to a dramatic slowdown in block creation and necessitated a chain reorganization from block 1,960,612. This reorg effectively wiped out nearly an hour of network activity, requiring users to resubmit transactions sent during that period. This incident marks the second significant outage for Starknet in less than two months, prompting fresh scrutiny over its reliability.

The network's native token, STRK, experienced a decline of over 3% following the outage. Starknet confirmed that the network was back online and fully operational, with block production returning to normal. The team acknowledged that transactions submitted between 2:23 AM and 4:36 AM UTC were not processed and committed to publishing a detailed retrospective analysis of the incident.

Despite the immediate challenges posed by the outage, the Grinta upgrade is a crucial step in Starknet's long-term strategy to decentralize its core infrastructure and improve scalability. The platform, developed by StarkWare, aims to provide a high-performance Layer 2 solution for Ethereum, with ongoing efforts towards full decentralization, including plans for decentralized validation and further performance enhancements through technologies like Cairo-Native.