Ethereum to shut down its biggest testnet Holešky after Fusaka fork
Ethereum’s largest testnet, Holešky, will be retired in the coming weeks as part of a planned shutdown and migration following the network’s Fusaka upgrade. The Ethereum Foundation announced that Holešky will be taken offline two weeks after Fusaka is finalized, and testing and infrastructure teams will stop supporting the network thereafter.
Holešky was launched in September 2023 to test staking infrastructure and validator operations. Over the last two years it enabled thousands of validators to trial major protocol upgrades, including Dencun and the more recent Pectra release, helping developers and operators prepare for mainnet changes.
In early 2025 Holešky experienced significant “inactivity leaks” that produced a large exit queue for validators. Although the network eventually recovered, the Foundation introduced a new testnet called Hoodi in March to provide a cleaner environment free of those issues. The plan is to migrate Holešky’s staking operators and supporting infrastructure to Hoodi, which already supports Pectra and will host future upgrades such as Fusaka.
For developers building smart contracts and decentralized applications, the Foundation recommended using Sepolia as the primary testnet while the migration takes place.
Fusaka (Fulu–Osaka) is scheduled to go live on mainnet in early November and is designed to improve how rollups access and store data by distributing data availability work more efficiently across validators. The upgrade — composed of multiple Ethereum Improvement Proposals — aims to make running nodes easier, strengthen decentralization and boost Layer‑2 scalability by helping rollups process transactions faster and at lower cost.
Looking further ahead, the Glamsterdam upgrade under EIP‑7782 is planned for 2026. One proposal under consideration would halve block times to six seconds by separating block validation from execution, giving zero‑knowledge EVM provers more time to generate proofs.
The Foundation framed these changes as part of a broader focus on improving user experience across the protocol stack, alongside ongoing work on staking, decentralization and scalability. Recent protocol progress has also coincided with increased institutional interest in Ether, which industry observers say has contributed to strong price moves this year.
Source: Cointelegraph