Ethereum completed the Hoodi testnet fork on October 28, marking the final preparatory phase before the Fusaka upgrade launches in December with expanded blob capacity and new data structures designed to improve Layer-2 scalability, according to Nethermind, a leading Ethereum execution client.
The testnet activation represents the final preparatory phase before Fusaka’s mainnet rollout in December, solidifying Ethereum’s progress toward enhanced scalability and network efficiency.
Despite the milestone, Ether (ETH) prices dipped over 2% to around $4,000, as traders remained cautious amid the U.S. Federal Open Market Committee (FOMC) meeting, which could influence global liquidity and risk sentiment. Historically, risk assets such as ETH exhibit volatility around interest rate decisions.
“The Hoodi Fork marks a key milestone on the road to Fusaka,” Nethermind developers said in a post on X.
The Ethereum fusaka upgrade is widely expected to usher in significant protocol changes that expand data capacity and optimize Layer-2 interactions, continuing Ethereum’s trajectory as the most decentralized and developer-active blockchain.
Ethereum fusaka upgrade builds on Pectra’s foundation
The Hoodi Fork follows earlier successful test deployments on Sepolia and Holesky networks earlier in October. Sepolia’s upgrade was executed on October 14, while Holesky testing began on October 1 before being decommissioned after verification.
The Ethereum fusaka upgrade succeeds the Pectra upgrade, which went live on the mainnet in May 2025. Pectra introduced pivotal improvements, including streamlined validator operations, account abstraction via EIP-7702, and increased blob capacity per block reducing Layer-2 transaction costs and boosting throughput.
Blobs, short for “binary large objects,” enable rollups to post transaction data more efficiently onto Ethereum, effectively lowering fees and expanding the network’s capacity. With Fusaka, developers plan to further increase Ethereum’s blob capacity and integrate new cryptographic data structures to improve scalability.
Ethereum’s roadmap is entering its next phase with Fusaka, said Christine Kim, Research Analyst at Galaxy Digital. Each upgrade brings us closer to a modular, scalable architecture capable of supporting global-scale applications.
Fusaka to introduce blob parameter forks and Verkle Trees
The Ethereum fusaka upgrade will be implemented in three key stages, beginning with mainnet activation on December 3. The initial rollout will introduce Peer Data Availability Sampling (PeerDAS) through EIP-7594, a feature designed to improve how nodes access and verify Layer-2 data.
Fusaka will also integrate Verkle Trees, an advanced data structure that offers more compact and efficient state proofs, allowing nodes to verify network state with less computational load. This upgrade is complemented by a higher block gas limit, which will improve overall throughput at the base layer.
Two subsequent Blob Parameter Only (BPO) forks will follow. The first, scheduled for December 17, will raise the number of blobs per block to 10 (maximum 15). The second, set for January 7, 2026, will further increase the blob count to 14 (maximum 21), effectively doubling Ethereum’s data capacity and reinforcing its Layer-2 scalability.
“These iterative forks are designed to ensure stability while steadily increasing network efficiency,” said Tim Beiko, Ethereum Foundation core developer. “The gradual approach reduces upgrade risk and provides time for ecosystem adaptation.”
Developers and traders await mainnet launch
The Ethereum fusaka upgrade is the culmination of years of development focused on scalability and decentralization. Following the successful Hoodi testnet, developers will now monitor network metrics, ensuring stability ahead of the December mainnet deployment.
While ETH’s price remained subdued amid macroeconomic uncertainty, analysts believe the upgrade could strengthen Ethereum’s long-term fundamentals. By boosting blob capacity, improving data sampling, and implementing Verkle Trees, Fusaka sets the stage for future performance gains and reduced transaction costs.
The Ethereum fusaka upgrade represents a critical infrastructure step toward mass adoption, said Alex Thorn, Head of Research at Galaxy Digital. Ethereum continues to set the standard for open innovation in blockchain.
The Ethereum Foundation has confirmed its long-term commitment to iterative network enhancements, aligning with Ethereum’s broader “rollup-centric roadmap” which is an approach that decentralizes scaling through Layer-2 ecosystems while maintaining the integrity of the base layer.
As the Ethereum fusaka upgrade moves toward mainnet activation, it will mark one of the most significant technical advancements since The Merge, reinforcing Ethereum’s position as the backbone of decentralized finance and Web3 innovation.
