Ethereum’s Glamsterdam upgrade hits its first public testnet
Updated: 6 days ago
TL;DR: Ethereum’s next major hard fork, Glamsterdam, reached its first public testnet on 6 October 2026, moving the network a step closer to enshrined proposer-builder separation.
What happened
Glamsterdam activated on the Sepolia testnet on 6 October 2026. It is a hard fork, meaning all node operators must update both their execution-layer and consensus-layer clients, and the Sepolia run targets a 200 million gas limit that could allow more transactions per block.
No mainnet date has been set. One will follow only after a successful testnet run, and Ethereum’s upgrade schedule has slipped before, so the timeline remains open.
Why the upgrade is significant
The headline change reported for Glamsterdam is enshrined proposer-builder separation, or ePBS, alongside features such as block-level access lists and revised gas pricing. ePBS bakes into the protocol a separation that currently relies on outside middleware.
That matters because it reshapes how blocks are built and reduces the network’s dependence on third-party infrastructure — a structural change rather than a cosmetic one.
The bigger roadmap
Glamsterdam is one of Ethereum’s most consequential structural upgrades in years, and the following fork, informally called Hegotá, is targeted for 2027 and has been described as potentially one of the network’s last ‘normal’ forks.
For businesses building on Ethereum, the practical signal is stability-through-change: the base layer keeps hardening, which lowers long-term platform risk even as each upgrade requires operators to keep their infrastructure current.
Quick FAQ
What is Glamsterdam?
It is Ethereum’s next major hard fork, which reached the Sepolia testnet on 6 October 2026. Its headline feature is enshrined proposer-builder separation (ePBS), along with changes such as block-level access lists and revised gas pricing.
When will it reach mainnet?
No mainnet date is set. A mainnet launch will follow a successful testnet run, and Ethereum’s schedules have slipped before.
Why does ePBS matter?
It moves proposer-builder separation into the protocol itself, reshaping how blocks are built and reducing reliance on outside middleware.
Ethereum keeps doing the unglamorous work of hardening its base layer, and that’s exactly why serious builders stay. Each upgrade is a maintenance cost today in exchange for lower platform risk tomorrow — a trade-off any business choosing long-term infrastructure should understand and value. — Daniel Nikolla, Founder of Merx Marketing
Enshrining proposer-builder separation is a structural upgrade, not a cosmetic one — the base layer keeps hardening, lowering long-term platform risk for builders.
How much does the long-term stability of the underlying platform weigh in your build-vs-buy decisions?
If you would like to know more about this topic, please contact us on danieln@merxmarketing.co.uk
Sources: Cointelegraph and 24/7 Wall St.
Related reading
Written by Daniel Nikolla, Founder of Merx Marketing Ltd and Marketing Minute
