Ethereum is about to get.. Faster, Cheaper, and Infinitely More Scalable. The Fusaka hard fork goes live today. Here’s everything you need to know 🧵👇

@ethereum 1/ What Fusaka Actually Is? Fusaka is Ethereum’s newest hard fork - a lean, efficiency-focused upgrade designed to boost rollups, reduce data costs, and improve validator performance. It’s not a flashy overhaul. It’s a scaling accelerator engineered for the 100,000+ TPS future.

2/ Why This Upgrade Matters Ethereum is now on a six-month upgrade cycle. After Pectra (May 2025), Fusaka continues the momentum: • Cheaper data for L2s • Bigger blob capacity • Stronger cryptography • Faster base layer throughput This is how Ethereum stays ahead of Solana + high-TPS L1s without compromising decentralization.

3/ It Goes Live TODAY Fusaka activates December 3, 2025, following: • Holesky testnet passed: Oct 1 • Sepolia + Sepolia-2 runs: September–October • Devnet finalization: Late November • Client lock-ins: October 14 + 28 All major clients (Geth, Prysm, Lighthouse, Besu, Teku) support it. Exchanges will auto-upgrade, zero user action needed.

4/ The Core Upgrade : PeerDAS (EIP-7594) This is the big one. Peer Data Availability Sampling massively boosts blob scaling. Direct impact: L2 fees (Arbitrum, Optimism, Base, zkSync) are expected to drop 40-60% This is the upgrade that unlocks mass rollup throughput.

5/ Cryptography Upgrades (EIP-7951) Support for secp256r1 is finally here. Why this matters: • It’s the dominant curve in Web2 • Used by Apple, Google, and hardware wallets • Enables Web2 → Web3 onboarding • Strengthens bridge + identity integrations Ethereum becomes more interoperable with legacy systems.

6/ Gas & Throughput Improvements Fusaka includes: • Incremental gas limit increases • Execution-layer optimizations • Better validator load handling • Faster block processing Ethereum’s base layer capacity moves toward 420+ TPS (pre-L2). The ecosystem-wide TPS jumps much higher.

7/ EVM Upgrades → Fusaka brings quiet but major improvements to the Ethereum Virtual Machine: → EOF (EVM Object Format): Cleaner contract structure → safer, cheaper, easier to optimize. → New Opcode (CLZ): Speeds up cryptographic operations and ZK proofs. → secp256r1 Support: Enables future FaceID / fingerprint-level login for Ethereum apps. A lean upgrade today that unlocks smoother UX tomorrow.

8/ Developer Benefits Developers get: • Early EOF improvements • Cheaper contract deployment • More predictable execution • Better tooling stability • Rollup-friendly architecture End result: Safer contracts, lower gas, simpler verification.

9/ What This Means for L2s Rollups are the biggest winners: • Cheaper blobs • More blobs • Faster proof verification • Higher DA bandwidth • Based rollups become more viable Arbitrum, Optimism, Base, zkSync, StarkNet...all see reduced costs.

10/ Economic Effects for ETH Three major impacts: 1️⃣ More blob usage = more ETH burn (EIP-1559 extends into rollup data) 2️⃣ More L2 activity = higher validator rewards (based sequencing + MEV flows) 3️⃣ Higher throughput = increased demand for staking Indirectly bullish ETH not because of the fork, but because of the activity it unleashes.