Ethereum Fusaka Upgrade Boosts Scalability and Security
The Ethereum network has undergone one of its biggest infrastructure updates in history, known as Fusaka. This update went live on December 3, 2025, and brought significant changes to how smart contracts execute, data blocks are carried, and developers write code on the network.
Fusaka combined twelve Ethereum Improvement Proposals (EIPs) across consensus and execution layers, including PeerDAS, which allows validator nodes to verify blob data without downloading it all. The update also introduced a block size cap and per-transaction gas cap to prevent large blocks from overwhelming validators as throughput increases.
Another key feature of Fusaka is the EVM Object Format (EOF), which restructures how Ethereum smart contracts separate code from data. This makes contracts easier to validate before execution, reduces runtime errors, and opens the door for faster JIT-style execution in future client implementations.
The impact of Fusaka on developers building against Ethereum smart contracts today requires them to retest gas assumptions against new opcode and code-size limits, monitor rollup fee behavior, and watch official client release notes. Contract addresses, balances, and existing deployments remain unaffected by the upgrade itself.