Ethereum’s Fusaka upgrade went live on the Hoodi testnet on Tuesday at around 18:53 UTC, on its final testnet ahead of mainnet launch. ETH’s Fusaka mainnet activation is expected before the end of the year.
After successive activations on Holesky and Sepolia earlier this month, Ethereum’s hard fork activation on Hoodi represents the third and final testnet deployment this year. The Ethereum Foundation previously predicted that Fusaka’s mainnet launch would begin at least 30 days after the Hoodi testing.
Ethereum’s next major upgrade, Fusaka, is now live on the Hoodi network! ✅
Fusaka mainnet activation is scheduled for December 3rd.
Fusaka introduces multiple EIPs to improve scalability, strengthen security, and reduce costs. The upgrade will unlock the next phase of rollup… pic.twitter.com/VQkosIouZQ
— Consensys.eth (@Consensys) October 28, 2025
Ethereum core developers had also scheduled the hard fork for December 3. The developers announced the launch date of the upgrade in the ACDC #165 developer call. The hard fork was activated on the Holesky testnet on October 1 and on the Sepolia testnet on October 14.
Ethereum’s latest hard fork on the Ethereum Virtual Machine (EVM) is aimed at establishing backend improvements to boost the efficiency, scalability, and security of the largest smart contract blockchain. Fusaka aims to increase ETH’s block gas limit from 30 million to 150 million units, aimed at supporting more transactions. The upgrade also seeks to expand blob capacity and introduce new node security features.
Fusaka will also include about a dozen Ethereum Improvement Proposals. The upgrade will primarily include EIP-7594, which introduces Peer Data Availability Sampling, also known as PeerDAS. PeerDAS enables validators to verify large datasets, or blobs, by sampling small portions from peer nodes instead of downloading entire datasets. The upgrade enables validators to survey data blocks rather than full blobs, thereby improving data availability for Ethereum’s Layer 2 ecosystem.
The next hard fork follows the audit contest for Fusaka launched by the Ethereum Foundation four weeks ago. The contest offered up to $2 million in rewards for security researchers who detect bugs before the hard fork reaches mainnet.
The audit contest, which ran from September 15 through October 13, was hosted on Web3 security platform Sherlock and co-sponsored by Gnosis and Lido. The Ethereum Foundation revealed that the contest also came with 2x rewards multipliers in week one and 1.5x in week two.
Ethereum’s last major upgrade, Pectra, was launched approximately six months before the introduction of the Fusaka hard fork. According to bi-weekly core dev calls, Ethereum researchers are already planning the roadmap for the next major protocol upgrade, Glamsterdam. The next hard fork will focus on faster block times and scalability enhancements, including the full EVM Object Format.
Tomasz K. Stanczak, the Ethereum Foundation’s co-executive director, previously urged core teams to prioritize the Fusaka hard fork and pause forward-looking debates about Glamsterdam. The Glansterdam upgrade is scheduled for early 2026.
In August, Stanczak called for coordination among the Ethereum community to ensure there are no delays to Fusaka. He warned at the time that slippage in coordination was putting deadlines at risk.
“I have suggested coordinators a few weeks ago to stop discussing Glamsterdam and focus on the delivery of Fusaka. Maybe sometimes less ACD calls may help with the process? Maybe the future fork calls should not be happening when the current fork testnet timelines are at risk?”
–Tomasz Stanczak, Co-Executive Director at the Ethereum Foundation.
The Glamsterdam upgrade is expected to include headline items such as enshrined proposer-builder separation (ePBS) at the protocol level—the upgrade blocks level access lists (EIP-7928) on the execution side.
Fusaka upgrade explainer for enterprises event in New Yorkhttps://t.co/3RThDKMac4
— Tomasz K. Stańczak (@tkstanczak) October 28, 2025
The Ethereum Foundation launched the Fusaka Upgrade Explainer for Enterprise event in New York on Tuesday. The event, slated for Friday, October 31, is offering an exclusive executive-level session with the Ethereum Foundation and the Protocol Guild to unveil what’s next for the network.
According to the report, the event will include a fireside chat between Trent from the Ethereum Foundation, Protocol Guild, and Redwan Meslem from the Enterprise Ethereum Alliance (EEA). The event also aims to delve into how Ethereum’s roadmap is evolving to meet the needs of global institutions and applications.
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