Network Upgrades

Blockchain networks periodically upgrade their protocol. Most upgrades do not affect CRE workflows, but some change how transactions are priced or executed. This page tracks upcoming upgrades that may require action from workflow developers.

Ethereum Glamsterdam

Ethereum is upgrading to Glamsterdam during Q4 2026. The Ethereum Sepolia upgrade is scheduled for 6 October 2026 at 13:53:36 UTC; Hoodi and Mainnet timings are still to be confirmed.

Glamsterdam changes the gas model of the chain. You do not need to do anything unless your workflow sets a gas limit, in which case see Preparation below.

Timelines

NetworkTimingImpact
Ethereum Sepolia6 October 2026, 13:53:36 UTCWorkflows writing to Ethereum Sepolia may fail 30 minutes before and after the upgrade.
Ethereum HoodiQ4 2026 (will be confirmed closer to the time)Workflows writing to Ethereum Hoodi may fail 30 minutes before and after the upgrade.
Ethereum MainnetQ4 2026 (will be confirmed closer to the time)Workflows writing to Ethereum Mainnet may fail 30 minutes before and after the upgrade.

Preparation

If your workflows set a gas limit, you may need to adjust it once the hardfork takes effect. The new gas limit value depends on how much storage versus compute your transactions use, so we cannot advise on how to adjust your limits.

To best prepare:

  1. Ahead of the Ethereum Sepolia upgrade, update your workflows to add extra gas headroom or unset the gas limit, and confirm they still succeed.
  2. After the Ethereum Sepolia upgrade on 6 October 2026, confirm whether your workflow's transactions still succeed. If they do, no more action is needed. If you still have a gas limit set and your transactions are reverting due to out of gas, increase your gas limit well above the previous Fusaka limit of 16,777,216.
  3. Ahead of the Ethereum Hoodi and Mainnet upgrade (date to be confirmed in Q4 2026), apply the same steps as Ethereum Sepolia to minimize impact to your workflows.

For details on configuring gas limits in your workflows, see Configuring gas limits and Writing data onchain.

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