Ethereum’s Glamsterdam hard fork entered its final devnet stage Tuesday, according to The Defiant. The team says this phase “locks in” the EIP bundle core developers expect to carry through public testnets and into mainnet activation in the second half of 2026.
The key operational detail in The Defiant’s update is the gas-limit target. Glamsterdam is being run with a goal of 200M for the gas limit. That number matters because it sets a concrete ceiling for execution capacity during testing. If the network struggles to hit it, or if clients diverge in behavior under load, you do not get a clean path to mainnet.
What “final devnet phase” actually means
In a protocol pipeline, “final devnet” is less about hype and more about risk management. The Defiant frames this stage as the point where core developers treat the EIP bundle as locked, then move it forward through the remaining public testnet runway. That implies less churn in the spec package, and more focus on implementation reality, like how widely client teams converge and how stable the upgrade feels under realistic conditions.
The 200M gas-limit target is the bottleneck test
Gas limits control how much work each block can pack. So 200M is not a vanity metric. It is a stress marker for:
- execution throughput under higher demand
- whether block production and client execution stay consistent
- whether the network’s resource assumptions hold when the EIP changes meet actual load
The Defiant’s framing ties Glamsterdam’s devnet phase to that capacity goal. For operators, that’s the kind of target you want before you get to a wider testnet cycle.
Timeline: devnets now, mainnet in 2026
The Defiant says the EIP bundle is expected to carry the network through public testnets and then into mainnet activation in the second half of 2026. That is a long runway, but also a long window for implementation gaps to show up. The “final devnet” milestone suggests the project wants those gaps exposed before mainnet, not after.
Also, note the scoping in The Defiant’s excerpt. It calls Glamsterdam “the largest protocol change since the …” but the provided text cuts off before finishing the comparison. Without the full sentence, the safest read is that core developers position Glamsterdam as major, not incremental. That should raise the scrutiny level on client coordination and upgrade safety.
What to watch next
Based on The Defiant’s description, the near-term watch item is whether the testnets under the locked EIP bundle actually behave as expected when pushing toward the 200M gas-limit target. If implementation or performance cracks appear late, they can force last-minute compromises. If they do not, the team gets a smoother handoff from devnet validation into public testnet scale testing.
For now, Glamsterdam is no longer in the “drafting” phase. It is in the “prove it under constraints” phase, with a specific gas-limit goal and a mainnet window in the second half of 2026.