Ethereum core developers have announced that the Fusaka upgrade will be implemented on the mainnet on December 3rd, provided testing goes as planned. The date was announced during the call for developers ACDC #165, considered the main reference for coordinating network changes.
Before its final launch, Fusaka will undergo testing in different environments. Activation on the Holesky testnet is scheduled for October 1st, followed by Sepolia on October 14th, and finally, Hoodi on October 28th. According to the developers, the final epoch parameters and timings are yet to be reconfirmed.
The goal of the update is to expand scalability without compromising decentralization and security. One of the most talked-about features is Peer Data Availability Sampling (Peer DAS), a mechanism that allows validators to verify large volumes of data through small samples from peer nodes, eliminating the need to download complete sets of data known as blobs. Blob capacity is expected to double within two weeks of activation.
Among other changes, the hard fork proposes raising the block gas limit from 30 million to 150 million units, expanding transaction capacity. The update also integrates Verkle Trees, a structure that optimizes data storage with more compact proofs, as well as improvements to the EVM (Ethereum Virtual Machine), accelerating smart contract execution.
As part of the preparation, the Ethereum Foundation launched a four-week audit competition. The program offers up to $2 million in rewards to security researchers who identify critical flaws before the official launch.
Developers have already indicated that the next major update after Fusaka will be Glamsterdam, scheduled for 2026. This upcoming hard fork is expected to introduce additional scalability improvements, such as full implementation of the EVM Object Format (EOF) and faster block times, solidifying the roadmap for improvements for the second-largest blockchain in the cryptocurrency market.