Ethereum will activate the Fusaka upgrade on mainnet on Dec. 3, 2025, aiming to relieve pressure on rollups by introducing PeerDAS, BPO forks, and history expiry tweaks. This upgrade aligns with the roadmap of Merge, Surge, Verge, Purge, and Splurge, focusing on scalability and data availability improvements.

Fusaka is the first upgrade to target all aspects of Ethereum’s roadmap at once, scaling data for rollups, history expiry, and lighter sync. It sets a goal for a modular Ethereum stack to achieve more than 100,000 transactions per second by combining L2 throughput with L1 settlement.

The core scaling change in Fusaka is EIP-7594, PeerDAS, which reduces bandwidth and storage by splitting rollup data into smaller cells and using sampling. BPO forks allow for smaller and more frequent capacity increases over time, while gas and block size updates create more flexibility for complex transactions.

Fusaka introduces user experience improvements, security enhancements, and developer tools such as deterministic proposer lookahead, P-256 support, and a count leading zeros opcode. History expiry extensions and optimizations aim to speed up sync for new validators, while making the protocol more efficient.

Analysts predict that Fusaka could reduce L2 data fees by 40%-60% over time, benefiting high-throughput use cases like DeFi and gaming. Node operators and validators will see lighter loads due to sampling and history expiry, but well-provisioned validators may shoulder more upload bandwidth with higher blob counts.

The next upgrade after Fusaka, Glamsterdam, is expected in 2026 with features like enshrined proposer builder separation and block-level access lists. Fusaka marks a turning point in Ethereum’s roadmap towards a coherent and value-aware scaling program, aiming to support a 100,000 TPS modular stack while maintaining decentralization.

Read more at Coin Telegraph: How the Fusaka Upgrade Advances Ethereum’s Long-Term Roadmap in 2025