One of the most complex upgrades in Ethereum's history: Glamsterdam reconstructs block building and gas billing

Author: Ethereum Foundation
Compiled by: Deep Tide TechFlow

Deep Tide Guide: The upcoming Glamsterdam upgrade for Ethereum brings a dual restructuring of block construction methods and Gas billing, causing any wallets, indexers, and estimators with hard-coded Gas limits to fail directly. The foundation has opened a public testnet in advance, providing developers with a few months of window, but time waits for no one.

tl;dr

Meet Platåberget: an early testing ground for the Glamsterdam (Gloas + Amsterdam) upgrade, now open for public participation. This upgrade will bring disruptive changes to application developers. Notably, any tools relying on hard-coded maximum Gas limits (such as wallets, indexers, and Gas estimators) will become ineffective and need updates. Please take advantage of this early opportunity for testing!

Platåberget is a short-term testnet designed for the community to test related changes. Unlike previous developer networks that lasted very briefly, Platåberget is planned to run for several months, providing the community with a stable environment to experience Ethereum after Glamsterdam and to have the opportunity to test and break things before Glamsterdam goes live on the longer-term testnets Sepolia and Hoodi.

What’s in the Glamsterdam Fork

The Glamsterdam upgrade brings significant changes to both the consensus layer and the execution layer. Highlights include:

• Built-in proposer-builder separation: This is a major change to the way blocks are constructed, proposed, and validated, including a new builder API process and PTC (load timeliness) checks. Infrastructure relying on block production and validation pipelines should expect to be affected.

• Block-level access lists: Introduction of mandatory block-level access lists that record accessed state locations and changes after transactions. Block-level access lists are stored separately from the block body and can be exchanged between execution layer nodes via eth/71.

• Gas repricing: This is a set of coordinated changes to Gas costs aimed at pulling the Gas lower limit to about 200 million. Any tools with hard-coded maximum Gas limits will be affected.

• Larger contracts and initialization code: The maximum deployable contract size is increased from 24KiB to 64KiB, and the maximum initialization code size is increased from 48KiB to 128KiB.

• Forward-compatible consensus data structures

The validator set for Platåberget is relatively small but publicly joinable. Anyone can deposit new validators and test their validator and builder deposit processes. ePBS is a significant change to the consensus layer, and we want to ensure that all independent stakers, DVT projects, custom software, and large-scale operators have ample opportunity to test their infrastructure. The Glamsterdam fork on the testnet is scheduled for August 20, allowing enough time to deposit and prepare for the fork transition.

Another significant change in Glamsterdam is Gas repricing. These changes will affect a broader audience as they touch every wallet, indexer, and Gas estimator on the network. Please take this opportunity to figure out which tools or assumptions in your system may encounter issues before the fork goes live on the mainnet.

A complete list of included EIPs is tracked in the Glamsterdam meta EIP-7773.

Using Platåberget

Please check the Platåberget resource page for a summary of the included EIPs, client support, and launch status; refer to the devnet-8 specification for network settings, configuration values, boot nodes, and client release information.

The Platåberget page provides a one-click network addition process to configure your EL and CL clients, along with a faucet providing testnet ETH for covering deposits and Gas fees.

Keep the following points in mind when running nodes:

• The public will be able to submit validator or builder deposits through the Dora browser.

• The genesis validator set will not pre-allocate automatic staking to a few entities but will guide through public deposits and allocate some ETH at genesis to help kickstart.

• Client releases: Releases for each client are optional, please check if the version you choose is included.

Client Images

Currently, please use our ethPandaOps container images below until the client teams prepare tagged release versions.

Consensus Layer

Execution Layer

Support and Feedback

If you find errors or issues in the specifications, the best feedback channel is the Ethereum R&D Discord server. If you prefer not to use Discord, you can also raise issues in the following specification repositories: consensus layer, execution layer, execution-apis, builder-specs, and beacon-APIs.

Platåberget provides the community with the opportunity to experience Ethereum after Glamsterdam and start discovering issues.

Gas repricing is particularly important for application developers: any tools relying on hard-coded maximum Gas limits (such as wallets, indexers, and Gas estimators) will become ineffective and need updates. We hope to see dApp and wallet developers testing on Platåberget alongside infrastructure operators, as these changes are most likely to catch downstream tools off guard.

Repricing involves more than just block Gas limits: the price of individual operations will also change, and EIP-8037 introduces a separate state Gas dimension for operations that create new states. Creating accounts, deploying code, or writing to new storage slots is now measured at a fixed cost per state byte (CPSB), charged at runtime rather than upfront. The actual consequence is that a standard ETH transfer is no longer always a fixed 21,000 Gas: transferring to an existing account still costs 21,000 (now broken down into TXBASECOST + COLDACCOUNTACCESS + TXVALUECOST), but sending funds to a non-existent account incurs an additional state Gas fee of STATEBYTESPERNEWACCOUNT × CPSB at runtime. Any assumptions that 21,000 covers all transfers or estimates that assume a single Gas dimension need to be re-evaluated: see EIP-2780 for the breakdown of intrinsic costs, and EIP-8038 for the increased costs of state access.

Once feedback is integrated into client software and specifications, a non-final developer network will follow within a month to test extreme consensus scenarios.

After these developer networks have been running stably for a while, the existing long-term testnets (Sepolia, Hoodi) will undergo the Glamsterdam fork. Once they complete the upgrade and remain stable, the next step will be the transition of the Ethereum mainnet to Glamsterdam 🎊.

For those who want to track progress in more detail, the best channels are the Ethereum R&D Discord server, All Core Dev calls, the Glamsterdam upgrade tracker, or the Glamsterdam development network GitHub repository from EthPandaOps.

Platåberget sees you 🐻‍❄️!