Ethereum opens Platåberget, its public testnet for Glamsterdam

Ethereum opened a new public testnet called Platåberget, built to trial the roughly ten EIPs scoped for the Glamsterdam upgrade ahead of any mainnet rollout, well before those changes reach production networks, the Ethereum Foundation announced on August 17.

Platåberget forks on August 20 and, unlike prior short-lived devnets, is designed to run for a few months so outside developers and node operators have real time to test against it rather than a narrow internal window. The testnet's name pairs with Glamsterdam's own naming convention: the upgrade's consensus-layer component is called Gloas, after a star, while the execution-layer component keeps the Amsterdam name from an earlier Devconnect host city, combining into "Glamsterdam." It's a small detail, but a fitting one for an upgrade that's stitching together consensus-layer and execution-layer work as tightly as this one does.

The headline changes being tested are EIP-7732, which enshrines proposer-builder separation directly into the protocol with a new builder API flow, and EIP-7928, which stores block-level access lists separately from the block body, a pairing developers see as core to unlocking parallel execution on Ethereum. Alongside those sit EIP-8007's gas repricing toward a roughly 200 million gas floor, EIP-7954's jump in maximum contract size from 24KiB to 64KiB and initcode from 48KiB to 128KiB, and a handful of smaller changes to consensus data structures and intrinsic transaction costs. Consensus-layer clients Lighthouse, Lodestar, Nimbus, Prysm, Teku, and Grandine are all part of the test, alongside execution-layer clients Besu, Geth, Erigon, Nethermind, Reth, Nimbus-EL, and EthRex. Having every major client implementation participate from the start is deliberate: a testnet that only a couple of clients support tends to miss the exact kind of consensus-edge-case bugs a change like enshrined proposer-builder separation is most likely to expose.

• Platåberget forks August 20 and runs for a few months, longer than typical short-lived devnets
• Tests roughly 10 EIPs bound for Glamsterdam, headlined by EIP-7732 (enshrined proposer-builder separation) and EIP-7928 (block-level access lists)
• Also includes EIP-8007's gas repricing, EIP-7954's larger contract size limits, and smaller consensus and intrinsic-cost changes
• All major consensus and execution clients are participating: Lighthouse, Lodestar, Nimbus, Prysm, Teku, Grandine; Besu, Geth, Erigon, Nethermind, Reth, Nimbus-EL, EthRex
• Next steps after Platåberget stabilizes: Sepolia and Hoodi testnets, then mainnet, with no firm mainnet date announced yet

Glamsterdam has already slipped its original timeline once, and this testnet phase itself is part of why: Ethereum previously pushed the upgrade's target window to Q3 2026, a move that hit ETH's price the same day. A longer-than-usual public testnet phase for changes this central to Ethereum's execution model, especially the enshrined proposer-builder separation, trades speed for a wider net of real-world testing before anything reaches mainnet, which is exactly the kind of caution traders have been watching for as they weigh ETH's price ahead of Glamsterdam. Whether that caution shortens the eventual mainnet timeline or extends it further depends on what Platåberget actually turns up over the coming months. For now, the only firm date on the calendar is the fork itself; everything past that runs on however long stability actually takes to reach.

None of this should be read as personalized investment advice.