Starknet, an Ethereum layer 2 network built on zero knowledge rollup technology, has experienced another episode of mainnet downtime, adding to a growing list of reliability concerns following multiple outages in 2025. The latest disruption comes as the project moves into 2026, raising fresh questions around network stability at a time when usage across decentralized finance and blockchain gaming continues to expand.
Network Halt Reported on X
The Starknet team confirmed the issue in a post on X, stating that the mainnet was facing downtime and that engineers were actively investigating the cause. The team said efforts were underway to restore full functionality as quickly as possible, but no immediate explanation was given for the outage. At the time of writing, the disruption had lasted for a little over two hours, with block production reportedly stalled during that period.
Users and developers relying on the network for smart contract execution and application activity were unable to process transactions while the issue persisted. External network trackers also showed signs of halted or delayed block creation, consistent with previous Starknet incidents.
What Starknet Does and Why It Matters
Starknet is a ZK rollup based scaling solution that processes transactions offchain before submitting cryptographic proofs to Ethereum. This design is meant to reduce congestion on Ethereum while offering lower fees and faster transaction throughput, all while inheriting the security guarantees of the Ethereum base layer.
Starknet mainnet is down. Source: Voyager Online
The network supports a range of use cases, including decentralized finance platforms, gaming applications, and experimental smart contracts. In recent months, Starknet has also highlighted its ambitions around Bitcoin DeFi, often referred to as BTCFi, positioning itself as infrastructure that could help bridge Bitcoin related financial activity into the Ethereum ecosystem.
Despite the disruption, the price of Starknet’s native STRK token remained largely stable at the time of reporting, suggesting limited immediate market reaction.
Not an Isolated Incident
This is not the first time Starknet has faced mainnet issues. Throughout 2025, the network experienced several outages that drew increased scrutiny from developers and users. One of the most serious incidents occurred in September, following the rollout of a major upgrade known as Grinta version 0.14.0.
That upgrade led to an extended halt in block production and required two chain reorganizations. Around an hour of onchain activity was reverted, forcing affected users to resubmit transactions. The disruption lasted for roughly nine hours, according to Starknet’s own incident report.
Earlier in the year, the network also faced a separate multi hour outage linked to sequencer problems. Independent monitoring services recorded multiple instances of slow or stalled block creation across 2025, painting a picture of recurring operational challenges.
Lessons From the 2025 Outages
In its postmortem of the September incident, the Starknet team cited a chain of technical issues, including failures at Ethereum RPC providers and software bugs that affected sequencer behavior. The report acknowledged shortcomings in monitoring and fault tolerance, and outlined plans for architectural improvements and better incident detection.
Those commitments included changes to reduce reliance on single points of failure and to improve how the network responds under stress. The latest downtime suggests that some of those challenges may still be unresolved, or that new issues have emerged as the network continues to evolve.
Team Response and What Comes Next
A Starknet representative said the team was working to repair the latest incident and restore normal operations. As of now, there has been no detailed explanation of the root cause, nor a timeline for a full post incident report.
For developers and users, the repeated disruptions underline the trade offs that still exist in newer layer 2 systems, particularly those pushing advanced cryptographic designs at scale. How Starknet addresses these reliability concerns in the coming months may play a key role in determining whether it can maintain developer confidence and compete with other Ethereum scaling networks.
