The Final Stage Before Public Testing
On June 16, 2026, Ethereum developers announced they had entered the final phase of work on the Glamsterdam upgrade — the network’s most significant technical transformation in years. The team launched what are known as devnets — private test networks containing the full set of planned protocol changes. This is the last internal stage before the upgrade moves to open public testing.
Parithosh Jayanthi, a core infrastructure developer at the Ethereum Foundation, described the moment as a turning point for the network. In his words, Glamsterdam will be “probably the largest fork we’ve had since the Merge” — referring to Ethereum’s transition to Proof-of-Stake back in 2022. He added that the upgrade “will change a lot of assumptions about Ethereum and set us up for much more scaling in the future.”
What Is Actually Changing
Glamsterdam is built around two central innovations. The first concerns how blocks are created on the network. Today, more than 80–90% of Ethereum blocks are built with the help of external relay networks — third-party intermediaries that validators must trust to behave honestly. The upgrade brings this entire process directly into the protocol, making block construction transparent and free from any external dependencies.
The second innovation relates to transaction throughput. Currently, the network processes transactions sequentially — one at a time. Glamsterdam introduces a mechanism that identifies which transactions can be executed simultaneously and runs them in parallel. This is projected to push the network’s capacity toward roughly 10,000 transactions per second, up from today’s figure of around 1,000.
The upgrade also includes a sweeping overhaul of gas fees. Developers aim to make the cost of using the network a more accurate reflection of real computational effort. Preliminary estimates suggest that the cost of a simple ETH transfer could fall by up to 71%, while the gas limit per block is set to rise from 60 million to 200 million.
A Name With Meaning
The name Glamsterdam is a compound of two parts: “Gloas” covers changes at the consensus layer — how network nodes agree on the state of the blockchain — while “Amsterdam” handles the execution layer, which determines how transactions are actually carried out. Both components are deployed simultaneously as a single unified upgrade.
When to Expect the Launch
No firm mainnet activation date has been set. Once the current round of internal testing concludes, the upgrade will move to public testnets — Holesky and Hoodi. Developers note that previous upgrades needed between two and four months of public testnet stabilization before going live. Taking that into account, analysts consider September through December 2026 the most realistic window for mainnet activation, though the team emphasizes that timelines may shift.
The upgrade after Glamsterdam has already been named — Hegotá — a sign that Ethereum’s development roadmap is moving forward with clear momentum.
