Ethereum has a date for its next big software update, but it is not the date anyone asked for. The network’s developers have scheduled the Glamsterdam upgrade to activate on the Sepolia testnet on Oct. 6, and Sepolia node operators must update both their execution-layer and consensus-layer clients before then. The upgrade brings three major changes: proposer-builder separation, block-level access lists and a new gas pricing system. What the source does not say is when the upgrade lands on mainnet.
The Upgrade’s Three Parts
Glamsterdam is the name developers have settled on for the next stage of Ethereum’s roadmap. The upgrade is designed to improve how the network handles transactions and blocks, though the full scope of its changes has not been fully detailed beyond the three headline features.
The first change is proposer-builder separation, which moves the handoff between specialized block builders and validators into Ethereum’s protocol. That reduces reliance on outside middleware, which is a practical improvement for the nodes that run the network. The upgrade also introduces block-level access lists, which record the accounts and storage locations used during each block. Finally, the upgrade changes gas pricing to better reflect the cost of creating and accessing data on Ethereum.
Contracts that rely on fixed gas stipends or hardcoded gas limits may require changes, according to the foundation. The foundation has not announced a date for the upgrade to land on the validator-focused testnet Hoodi or on mainnet. That is the key gap in the rollout timeline.
Sepolia’s Role
Sepolia is a testnet, and developers use it to check that changes work as intended before they move them to the live network. The fact that Glamsterdam is activating there first is standard procedure, but it also means the mainnet date remains open.
The foundation’s announcement from Monday confirmed the schedule and the client updates required. Sepolia node operators need to update both their execution-layer and consensus-layer clients before the activation. That is a real task for the people running those nodes, even if it is a routine one.
What Is Still Missing
The mainnet date is the big unknown. Developers have not set a date for Glamsterdam’s rollout on Hoodi or on mainnet. Testnets exist to catch problems before they hit the live network, and Sepolia is doing exactly that.
The upgrade’s technical details are clear. The rollout timeline is not. That is the honest position to hold, and it is the one the foundation has taken.
The Long Road Ahead
Developers are targeting 2027 for Hegotá, the upgrade expected to follow Glamsterdam. That is a long way off, and it gives the current upgrade room to settle before the next one arrives. Hegotá could be the network’s last “normal” fork before development shifts toward recursive STARKs, automated formal verification, optimized consensus and quantum-safe cryptography, according to Ethereum co-founder Vitalik Buterin, who said Sunday that Hegotá could be the network’s last “normal” fork before development shifts toward those technologies.
Buterin’s framing matters because it suggests a shift in how Ethereum upgrades are built. Normal forks are familiar: they add features, fix bugs and move the network forward. The technologies he named are not normal. Recursive STARKs, automated formal verification, optimized consensus and quantum-safe cryptography are all research areas, and building them into the protocol would mark a fundamental change in how Ethereum operates.
That is a long way from the block-level access lists and gas pricing changes in Glamsterdam. The two upgrades sit on different timelines and different technical bases. Glamsterdam is about making the existing system work better. Hegotá is about remaking parts of the underlying architecture.
Related News
There is related news worth noting. Ethereum Institutional signals support for Ethlabs’ motion to reduce Ethereum block times. That is a separate proposal, and it is not directly tied to Glamsterdam. But it shows the broader context: Ethereum is moving through a period of active experimentation, with multiple proposals floating at once.
The Institutional signal supports Ethlabs’ motion to reduce block times, which is a distinct issue from the upgrade itself. It is worth keeping in mind, because the two proposals are working toward similar goals from different directions.
What To Watch Next
The next few weeks will show whether the upgrade holds together on Sepolia. If it does, the path to mainnet gets clearer. If it does not, the rollout timeline will stretch further. Either way, the foundation has been transparent about what it knows and what it does not know.
The upgrade activates on Oct. 6. The mainnet date is still unset. That is the whole story, and it is a fair one to tell.
Key Facts Box
- Glamsterdam upgrade activates on Sepolia testnet on Oct. 6
- Sepolia node operators must update execution-layer and consensus-layer clients
- Mainnet rollout date for Glamsterdam has not been set
- Developers target 2027 for Hegotá, the upgrade after Glamsterdam
- Vitalik Buterin called Hegotá “normal” fork before development shifts toward recursive STARKs, automated formal verification, optimized consensus and quantum-safe cryptography
The Timeline So Far
Here is how the rollout stands now:
- Glamsterdam activates on Sepolia testnet on Oct. 6
- Sepolia node operators must update both execution-layer and consensus-layer clients
- Mainnet rollout date for Glamsterdam has not been set
- Hoodi rollout date for Glamsterdam has not been set
- Developers target 2027 for Hegotá, the upgrade after Glamsterdam
The upgrade has a date. The network does not. That is the situation, and it is likely to stay that way until the Sepolia test runs complete.
Source material: “Ethereum schedules Glamsterdam upgrade on Sepolia for Oct. 6,” Cointelegraph.
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