Holesky disappears: Ethereum's most used testnet unexpectedly shuts down after Fusaka's switch

The unexpected shutdown of Holesky, the most widely used testnet by Ethereum developers, raises questions about the next steps and the impact of the switch to Fusaka. Here's everything you need to know.

Ethereum officially bids farewell to Holesky, its largest and most widely used testnet, after announcing its permanent shutdown following the Fusaka fork. The Ethereum Foundation confirmed that Hoodi will be the new test network in the coming weeks, marking a strategic shift in its roadmap. 

While Holesky's closure announcement may seem abrupt, it is part of a technical evolution aimed at improving efficiency and preparing for upcoming milestones for the blockchain protocol.

Holesky: The Starting Point for a New Era in Ethereum Validation

Since its launch in 2023, Holesky has become Ethereum's most robust test environment, designed to simulate large-scale validation operations. Its purpose was clear: to offer a network capable of more faithfully replicating mainnet behavior, especially in staking contexts and critical upgrades like Dencun and Pectra. 

For over two years, developers, node operators, and infrastructure teams have relied on Holesky to validate their deployments before bringing them to production on the mainnet.

However, the activation of the Pectra testnet earlier this year exposed technical limitations that compromised its functionality. According to the Ethereum Foundation, issues of congestion, prolonged downtime, and difficulties in node synchronization were encountered. These problems, which began to accumulate, affected the reliability of the environment. The Foundation acknowledged these drawbacks in a release recent official, indicating that Holesky had served his term and that it was time to move on.

Thus, despite the flaws presented, Holesky is leaving an important legacy. The organization emphasized that this testnet provided key learnings on mass validation and protocol testing, directly contributing to Hoodi's design and improving testing practices across the ecosystem. Therefore, its closure is not a failure, but rather a transition to a more agile infrastructure, prepared for the challenges ahead.

Hoodi Takes Over: A New Era of Ethereum Testing

The arrival of Hoodi marks the beginning of a new phase in Ethereum's testnet strategy. Designed to overcome Holesky's limitationsThis network aims to offer greater stability, compatibility with the latest updates, and a more fluid experience for developers and validators. Its launch is planned for the coming weeks, and the Ethereum Foundation has already begun recommending the migration of tools and workflows to this new network.

“Staking operators and infrastructure providers should migrate to Hoodi, which was launched specifically to address Holesky limitations. Hoodi provides a new set of validators, supports all Pectra features, and will enable future protocol upgrades, including the upcoming Fusaka hard fork.”, the Foundation noted. 

Hoodi not only addresses the technical issues of its predecessor but also aligns with the requirements of Fusaka, the upcoming Ethereum hard fork. This compatibility is key to ensuring that Fusaka's pre-deployment testing is conducted in a reliable and representative environment. Additionally, Hoodi incorporates improvements in synchronization architecture, node management, and load simulation, making it a more robust option for infrastructure testing.

For developers of smart contracts and decentralized applications, the Foundation suggests continuing to use sepolia as the main testnet. Hoodi, on the other hand, is positioned as the ideal environment for staking testing, validation, and protocol updates. This segmentation responds to a more refined testing logic, where each network fulfills a specific function within the ecosystem.

The transition to Hoodi involves not only a technical change, but also an evolution in the way Ethereum approaches experimentation and validation. With a more modular and resilient architecture, Hoodi promises to become the new standard for large-scale testing, paving the way for the advancements that Fusaka will bring.

Fusaka and the future of Ethereum

Fusaka represents much more than a simple technical update: it is The next big leap in Ethereum's evolutionScheduled for November, this update, which will be implemented as a hard fork, seeks to improve data availability for rollups, reduce transaction costs, and accelerate the execution of operations on the main network. In other words, Fusaka is the answer to the demands for scalability and efficiency that have dominated the ecosystem's agenda in recent years.

In essence, Fusaka takes the concept of the data blobs, initially implemented in the Dencun upgrade, and takes it to a new level of optimization. These blobs are essential for improving the functionality of rollups, which are second-layer solutions responsible for grouping multiple transactions into a single package. Thanks to this improvement, rollups will be able to operate much faster and with significantly reduced transaction costs, bringing Ethereum closer to the long-awaited vision of a scalable and accessible network for everyone.

In addition, Fusaka introduces improvements to execution logic and cross-layer interaction, which will directly impact the end-user experience.

In this context, testnets like Holesky and Hoodi have been instrumental, allowing each technical step to be validated before implementation on the mainnet, reducing risks and ensuring that updates work as expected. The shutdown of Holesky and the transition to Hoodi are not isolated events, but rather part of a broader narrative: that of a network that constantly evolves, learning from its mistakes and adapting to new demands.

Looking to the future, Fusaka, along with Hoodi, represents the Ethereum ecosystem's commitment to growth that is not only technological, but also more mature, efficient, and decentralized. Every technical decision and every upgrade is part of a story that continues to redefine what it means to build and trust this blockchain ecosystem.