Glamsterdam, Ethereum's next major protocol upgrade, is expected to go live in November 2026.
This isn't just another update.
Glamsterdam will introduce structural changes to how Ethereum operates, improving the way the network handles execution, scalability and efficiency.
As ETH continues to gain momentum, attention will inevitably shift toward what's coming next.
And what's next is Glamsterdam. 🐻
Glamsterdam with EIP-7928 (Block-Level Access Lists) is approaching the final mile, and things look great:
* Significant throughput increase thanks to parallelism
* Faster and simpler sync via snap v2
* Future-compatible with zkEVMs, partially stateful nodes, inclusion lists, and trie migrations
When we started working on the idea, we saw it as a nice scaling feature and didn’t yet realize that adding state diffs would have a bunch of positive side effects: making tracing faster, improving inclusion list quality under FOCIL (EIP-7805), and helping nodes catch up faster after being offline.
Glamsterdam will be one of the biggest forks we’ve seen, and it took correspondingly long, but the result will be worth it.
It's official. ♦️🐻
Glamsterdam is confirmed for Q4 2026.
The next major Ethereum upgrade is coming.
You can follow the development directly on Ethereum's official website.
Glamsterdam is getting closer.
🔓 Ethereum Foundation Details Glamsterdam Upgrade Progress, Announces Protocol Cluster Leadership Changes
The Ethereum Foundation released its May 2026 Protocol Cluster update, confirming advancements in testing and preparations for the upcoming Glamsterdam upgrade during an interop event in Svalbard, Norway.
Leadership changes within the Protocol Cluster were also announced, with Barnabé Monnot and Tim Beiko departing the Foundation, and Alex Stokes taking a sabbatical. Will Corcoran, Kev Wedderburn, and Fredrik will assume the roles of new Protocol Cluster leads.
$200 buyback of $GLAMSTERDAM has been executed.
On top of that, we airdropped supply to @VitalikButerin , bringing the creator of Ethereum into the Glamsterdam narrative.
More strategic buybacks are coming.
The Pectra Grants Round funded 10+ projs to help the ecosystem prepare for Pectra. Now we're doing it again for Glamsterdam.
If you work on Ethereum tooling, validator tools, monitoring, research, etc. to help prepare for the Glamsterdam upgrade, we want to hear from you.
👇👇
Finally, the block building pipeline.
In Glamsterdam, Ethereum is getting ePBS, which lets proposers outsource to a free permissionless market of block builders.
This ensures that block builder centralization does not creep into staking centralization, but it leaves the question: what do we do about block builder centralization? And what are the _other_ problems in the block building pipeline that need to be addressed, and how? This has both in-protocol and extra-protocol components.
## FOCIL
FOCIL is the first step into in-protocol multi-participant block building. FOCIL lets 16 randomly-selected attesters each choose a few transactions, which *must* be included somewhere in the block (the block gets rejected otherwise). This means that even if 100% of block building is taken over by one hostile actor, they cannot prevent transactions from being included, because the FOCILers will push them in.
## "Big FOCIL"
This is more speculative, but has been discussed as a possible next step. The idea is to make the FOCILs bigger, so they can include all of the transactions in the block.
We avoid duplication by having the i'th FOCIL'er by default only include (i) txs whose sender address's first hex char is i, and (ii) txs that were around but not included in the previous slot. So at the cost of one slot delay, only censored txs risk duplication.
Taking this to its logical conclusion, the builder's role could become reduced to ONLY including "MEV-relevant" transactions (eg. DEX arbitrage), and computing the state transition.
## Encrypted mempools
Encrypted mempools are one solution being explored to solve "toxic MEV": attacks such as sandwiching and frontrunning, which are exploitative against users. If a transaction is encrypted until it's included, no one gets the opportunity to "wrap" it in a hostile way.
The technical challenge is: how to guarantee validity in a mempool-friendly and inclusion-friendly way that is efficient, and what technique to use to guarantee that the transaction will actually get decrypted once the block is made (and not before).
## The transaction ingress layer
One thing often ignored in discussions of MEV, privacy, and other issues is the network layer: what happens in between a user sending out a transaction, and that transaction making it into a block? There are many risks if a hostile actor sees a tx "in the clear" inflight:
* If it's a defi trade or otherwise MEV-relevant, they can sandwich it
* In many applications, they can prepend some other action which invalidates it, not stealing money, but "griefing" you, causing you to waste time and gas fees
* If you are sending a sensitive tx through a privacy protocol, even if it's all private onchain, if you send it through an RPC, the RPC can see what you did, if you send it through the public mempool, any analytics agency that runs many nodes will see what you did
There has recently been increasing work on network-layer anonymization for transactions: exploring using Tor for routing transactions, ideas around building a custom ethereum-focused mixnet, non-mixnet designs that are more latency-minimized (but bandwidth-heavier, which is ok for transactions as they are tiny) like Flashnet, etc. This is an open design space, I expect the kohaku initiative @ncsgy will be interested in integrating pluggable support for such protocols, like it is for onchain privacy protocols.
There is also room for doing (benign, pro-user) things to transactions before including them onchain; this is very relevant for defi. Basically, we want ideal order-matching, as a passive feature of the network layer without dependence on servers. Of course enabling good uses of this without enabling sandwiching involves cryptography or other security, some important challenges there.
## Long-term distributed block building
There is a dream, that we can make Ethereum truly like BitTorrent: able to process far more transactions than any single server needs to ever coalesce locally. The challenge with this vision is that Ethereum has (and indeed a core value proposition is) synchronous shared state, so any tx could in principle depend on any other tx. This centralizes block building.
"Big FOCIL" handles this partially, and it could be done extra-protocol too, but you still need one central actor to put everything in order and execute it.
We could come up with designs that address this. One idea is to do the same thing that we want to do for state: acknowledge that >95% of Ethereum's activity doesn't really _need_ full globalness, though the 5% that does is often high-value, and create new categories of txs that are less global, and so friendly to fully distributed building, and make them much cheaper, while leaving the current tx types in place but (relatively) more expensive.
This is also an open and exciting long-term future design space.
https://t.co/CdpE9ugFxE
Glamsterdam reflects the long-term design philosophy promoted by Vitalik Buterin, Tim Beiko, and the Ethereum Foundation.
The goal isn’t speed at all costs, but neutrality, decentralization, and long-term resilience.
Like or repost if you want more threads breaking down how Ethereum actually works inside the blocks.
🧵 Ethereum’s next major upgrade: GLAMSTERDAM
Read this to understand how Glamsterdam is a game changer for Ethereum.
What is it?
Why does it matter?
And why it’s a big deal for Ethereum’s future 👇
Glamsterdam also introduces block-level access lists, an idea long discussed by Ethereum researchers, including @VitalikButerin, @TimBeiko
This lets Ethereum know in advance which parts of the state a block will touch, making execution more efficient and laying the groundwork for future scalability improvements.