Ethereum successfully activated its Fusaka upgrade on Wednesday, 3 December, introducing a set of execution-layer refinements aimed at improving client performance and preparing the network for further enhancements in 2026.
The upgrade went live at slot 13,164,544, marking the latest milestone in Ethereum’s steady upgrade cycle.
Fusaka followed Ethereum’s regular biannual cadence and delivered a range of stability and efficiency improvements across client implementations.
Although not a headline-changing fork like Dencun or Shanghai, the upgrade played an important role in maintaining compatibility and alignment across the execution layer.
What Fusaka introduced
The upgrade introduced several technical adjustments aimed at maintaining client team synchronization and ensuring seamless network operation. These included:
- Refinements to specific opcode edge-case handling
- Minor optimizations to block validation paths
- Under-the-hood client performance improvements
- Foundational adjustments preparing for upcoming EIPs expected in 2026
- Fusaka’s scope remained intentionally conservative, focusing on stability rather than major feature rollout.
Post-upgrade network conditions remained stable
Shortly after activation, Ethereum’s validator ecosystem continued operating normally. According to beaconcha.in data recorded immediately after the upgrade:
- Active validators: 995,908
- Staked ETH: 35.63M ETH
- Avg. validator balance: 35.84 ETH
- Joining / Exiting in past 30 days: 643K / 1,382K ETH
No meaningful dip in participation was observed during the first epoch following Fusaka, and block proposals continued uninterrupted.


Source: Beaconcha.in
The staking ecosystem remained dominated by Lido, Binance, Coinbase, ether.fi, and Figment — with Rocket Pool, Kiln, StakeWise, and several smaller operators contributing to overall decentralization.
The presence of “Unknown” validators reflects continued permissionless growth in the staking landscape.
ETH price rose ahead of the upgrade
ETH traded above $3,150 following the upgrade, extending a multi-day recovery. The market appeared to be pricing in a clean activation, with ETH breaking through the $3,000 psychological barrier and showing renewed bullish momentum.


Source: TradingView
The chart structure indicates:
- Strong bounce from ~$2,620 support
- Breakout above short-term resistance
- A shift in sentiment ahead of December macro events
Market reactions to execution-layer upgrades are typically muted unless disruptions occur — and Fusaka followed that pattern with a neutral-to-positive response.
Final Thoughts
- Fusaka’s successful activation reinforces Ethereum’s track record of reliable scheduled upgrades and strong coordination among client teams.
- With no post-fork instability detected, attention now shifts to upcoming EIPs in 2026 and the continued growth of rollup-centric infrastructure.
Source: https://ambcrypto.com/ethereum-completes-fusaka-upgrade-with-stable-network-performance/