Ethereum devs won’t fork Glamsterdam on Hoodi until smart contract risks resolved

Ethereum developers postponed Glamsterdam’s implementation on the Hoodi testnet. The delay concerns the testnet fork, which is a planned network upgrade rehearsal. Developers want to investigate whether Glamsterdam could disrupt existing smart contracts before allowing this stage to continue.

The concern involves EIP-8037 and EIP-8038. These proposals change how Ethereum charges gas for certain operations. Some contracts assume particular operations always cost specific amounts, especially when an external call fails. Those fixed assumptions could become invalid.

The Ethereum Foundation said Hoodi will not fork until the issues are resolved. Developers now have more time to inspect affected contracts, understand the risks, and decide whether changes are necessary. Glamsterdam already went live on Sepolia on October 6, but the Hoodi delay shows that mainnet preparation remains unfinished.

Glamsterdam is a planned Ethereum upgrade focused on improving the network’s layer-1 scaling roadmap. It includes several changes, including new gas pricing rules. The upgrade is being tested on Ethereum testnets before possible mainnet deployment.

EIP-8037 and EIP-8038 are the two proposals at the center of the current concern. They change how gas is charged for certain operations. That matters because some existing Ethereum projects were designed around assumptions that those operations would always consume particular amounts of gas.

Glamsterdam went live on the Sepolia testnet on October 6, one of its final major rehearsals. However, developers delayed its Hoodi fork after ChainSecurity reported possible contract breakage when external calls fail. The Ethereum Foundation said the testnet fork must wait while developers investigate the risks and decide whether changes are needed.

The number under investigation is eight: Ethereum developers are examining eight smart contract invariants connected to EIP-8037 and EIP-8038. These invariants represent conditions or assumptions that contracts expect to remain true while they operate.

In this case, the protected assumptions concern gas. Some Ethereum projects rely on particular operations costing a specific amount. ChainSecurity reported that these assumptions could fail when an external call does not succeed. A contract may then behave differently from what its developers expected.

The issue matters because smart contracts execute according to programmed rules. If an upgrade changes gas accounting, contracts with rigid gas expectations may encounter unexpected outcomes. Developers delayed the Hoodi fork so they can identify affected contracts, assess the risks, and determine whether fixes or changes are necessary before Glamsterdam moves closer to mainnet.

Smart contracts can depend on a particular gas cost when they perform an operation. If EIP-8037 or EIP-8038 changes that cost, the contract’s built-in expectation may no longer match Ethereum’s actual accounting. The risk is especially important when another contract call fails.

For example, a contract might expect a failed external call to consume a known amount of gas and use that expectation to continue, stop, or handle the failure. If the new rules charge a different amount, the contract could have less or more gas than anticipated. Its later instructions might then fail or follow an unintended path.

ChainSecurity identified this risk in its October 13 report. Ethereum developers are investigating eight related invariants before the Hoodi fork. The delay gives them time to find vulnerable assumptions and decide whether the proposals, affected contracts, or both need changes.

Hoodi and Sepolia are Ethereum testnets used to trial major network changes before they reach mainnet. A testnet rehearsal lets developers observe how an upgrade affects software and smart contracts without immediately changing Ethereum’s main production network.

Glamsterdam went live on Sepolia on October 6, which the Ethereum Foundation described as one of its final major rehearsals. The later Hoodi fork was delayed after concerns emerged about eight smart contract invariants. This sequence shows how separate testnet stages can reveal different risks.

Testing also gives developers time to investigate problems and decide whether changes are required. In this case, the Hoodi fork will not proceed until the security concerns are resolved. That protects the upgrade process from moving forward while contracts may still rely on outdated gas assumptions.

Glamsterdam includes two major changes besides gas-pricing adjustments. The first is enshrined proposer-builder separation. The second is block-level access lists. The Ethereum Foundation presented both as part of Ethereum’s layer-1 scaling roadmap.

The article does not explain their technical operation in detail. It does state that these features accompany gas changes intended to better reflect the cost of execution. Together, they form a broader upgrade rather than a single adjustment to transaction fees or operation costs.

Glamsterdam reached the Sepolia testnet on October 6, but its Hoodi rollout is paused. Developers must first resolve concerns connected to the gas-related proposals and eight smart contract invariants. The wider scaling goals remain part of the upgrade’s stated purpose, while the next step depends on completing the security investigation.

Gas is Ethereum’s unit for measuring the computational work required to process operations. Users pay for gas so the network can account for execution rather than treating every operation as equally costly. This helps reflect the resources different instructions require. The article discusses gas because Glamsterdam would change charges for certain operations.

A simple example is that a more demanding operation can require more gas than a simpler one. Smart contracts may also make assumptions about how much gas an operation consumes. If a proposal changes that amount, especially after a failed external call, a contract’s fixed expectation may become wrong.

The article says EIP-8037 and EIP-8038 aim to make gas pricing better reflect execution costs. It also reports that some projects could be affected. Developers therefore delayed the Hoodi fork while investigating eight invariants and deciding whether changes are necessary.