Ethereum Sepolia Upgrade
Ethereum schedules Glamsterdam upgrade for Sepolia testnet testing on October 6, 2026.
Anonymous
Key Points
1
Glamsterdam combines two upgrade tracks: “Gloas” for consensus-layer changes and “Amsterdam” for execution-layer changes, following Ethereum’s convention for naming major upgrades.
2
The proposed Sepolia activation is scheduled for October 6, 2026, at 13:53 UTC, although the timing remains part of the testnet rollout plan rather than a finalized mainnet schedule.
3
Enshrined proposer-builder separation is intended to reduce Ethereum’s reliance on off-protocol MEV relays, which currently coordinate validators and block builders but introduce additional centralization and trust risks.
4
Nethermind’s benchmark completed all 2,302 block-level access-list tests, processing 570.7 billion gas in three minutes and 15 seconds—about 2.9 billion gas per second—though the result measured client execution rather than full-network performance.
5
Developers said existing defenses generally switch to locally built blocks only after several missing payloads, and they are considering ways for clients to reject individual builders more effectively so attackers cannot easily return with new identities after being blocked.
Ethereum developers have scheduled the Glamsterdam upgrade for testing on the Sepolia testnet on October 6, 2026, marking the next major step toward a network overhaul designed to reduce fees and cut reliance on external builders CoinCodex. The upgrade combines consensus-layer and execution-layer improvements, with a tentative second test planned for October 27 and a broader fourth-quarter mainnet target KuCoin.
The changes include enshrined proposer-builder separation to reduce centralization risks and block-level access lists that could slash transaction fees by up to 78.6% for common operations Crypto-Economy. However, developers warned that attackers could exploit inexpensive test ether and temporary builder identities to disrupt the testnet without risking real funds.
Glamsterdam Combines Two Upgrade Tracks into One
Glamsterdam merges two separate Ethereum improvement projects. Gloas handles consensus-layer changes while Amsterdam addresses execution-layer upgrades CoinCodex. This combined approach follows Ethereum's naming convention for major releases and streamlines development across the protocol's two main components.
New Builder Separation Could Cut Out Middlemen
The upgrade introduces enshrined proposer-builder separation directly into the protocol. Today, external MEV relays coordinate validators and block builders but add centralization and trust risks Crypto-Economy. The new approach removes this middleman layer and gives the network more control over block creation.
Access Lists Enable Dramatic Fee Reductions
Block-level access lists are set to unlock parallel transaction processing on Ethereum. Recent devnet testing raised the gas limit from 60 million to 200 million without losing finality Yahoo Tech. One estimate projects a 78.6% fee reduction for common operations once deployed to mainnet.
Nethermind completed a benchmark running 2,302 access-list tests and processed 570.7 billion gas in three minutes and 15 seconds. This speed — roughly 2.9 billion gas per second — demonstrates client-level performance but does not yet reflect full-network conditions CoinCodex.
Developers Brace for Fake Builder Attacks on Testnet
Ethereum developers warned that attackers could use free test ether to fund block auctions with disposable builder identities. These bad actors could withhold transaction payloads and disrupt Sepolia testing without endangering real funds KuCoin. The attack requires minimal cost since testnet ether has no value.
Current defenses switch to locally built blocks only after multiple missing payloads occur. Developers are considering stronger safeguards to let clients reject individual builders more quickly and prevent attackers from returning with new identities Crypto-Economy. Client teams must release Sepolia-compatible software by September 29.
Sentiment
Mostly PositiveNEGATIVENEUTRALPOSITIVE
Publishers
21
Articles
3
Reach
24
A
AnonymousAuthor
