26-8-2025 – Ethereum’s Fusaka Devnet 5 is slated for release next Wednesday, September 3, 2025, according to Christine Kim, Vice President of Research at Galaxy, who shared the update on social media. The testnet marks a critical step in preparing for the Fusaka mainnet launch, targeted for early November 2025.The Fusaka upgrade, combining the Fulu consensus layer and Osaka execution layer, aims to enhance Ethereum’s scalability and efficiency.
Devnet 5 will focus on testing validator custody features, distributed blob building, and data column sidecars, building on prior devnets’ progress. These features are designed to optimize Layer 2 data throughput and improve smart contract execution, with key Ethereum Improvement Proposals (EIPs) like PeerDAS under scrutiny. Developers have emphasized rigorous testing to ensure stability, especially after dropping complex proposals like EIP-7907 to avoid delays.
The November mainnet target hinges on successful devnet and public testnet phases, with client teams working to align consensus and execution layer implementations. Recent discussions highlighted the need to prioritize Fusaka over the subsequent Glamsterdam upgrade to meet the tight timeline, particularly with Devconnect looming in November. Any setbacks in Devnet 5 could push the schedule into 2026, impacting Ethereum’s scaling roadmap.
