19.09.2025 16:00

According to internet sources, Ethereum's core developers have officially announced the activation date for the highly anticipated Fusaka upgrade: December 3rd. This major protocol enhancement is designed to improve network scalability while driving down transaction costs.

Following successful trial runs on the Holesky, Sepolia, and Hoodi test networks in October, the stage is now set for the mainnet deployment. Further bolstering the upgrade's security, the Ethereum Foundation, in collaboration with Gnosis and Lido, initiated a $2 million audit contest on September 15th, hosted on Sherlock, to identify vulnerabilities prior to the mainnet launch. This contest, running for four weeks, underscores the commitment to a secure and robust upgrade.

The December 3rd launch date was determined during All Core Developers Consensus (ACDC) Call #165. A key component of Fusaka is the introduction of Peer Data Availability Sampling (PeerDAS) via EIP-7594. This innovative mechanism enables nodes to verify only portions of large data blobs, minimizing bandwidth demands and scaling blob storage, which is crucial for Layer-2 rollup efficiency.

Currently, data from Blockworks Research reveals that blob utilization for major rollups is consistently high, with Arbitrum One and OP Mainnet registering 99.6% and 99.2% respectively. With median blob fees ranging from $0.49 to $3.05 per MiB, Fusaka's Blob Parameter Only (BPO) forks are intended to alleviate this congestion by expanding blob limits.

Two BPO forks are slated for deployment post-Fusaka activation. The initial fork, expected around December 17th, will increase the maximum blob count from 9 to 15. A subsequent fork, planned for January 7th, 2026, will further increase the limit to 21. According to Ethereum researcher Christine Kim, these forks represent lightweight adjustments to blob parameters and will not necessitate client updates.