ETH developers alert L1 contracts before upgrade

TLDR

Ethereum developers have warned maintainers of certain Layer 1 smart contracts about potential breakage from the upcoming Glamsterdam gas repricing upgrade and are proactively alerting them ahead of mainnet activation.

1. Glamsterdam will change how gas is charged for state creation and storage via EIP-8037 and EIP-8038, and developers have identified a small set of L1 contracts that could fail without changes.
2. Contracts that hardcode gas budgets, rely on 2,300-gas stipends, or use brittle `gasleft` logic are most at risk, but most issues can be fixed by adjusting gas limits and assumptions.
3. The alerts are part of a broader push to test contracts on devnets and testnets before a targeted Q4 2026 mainnet fork, paving the way for roughly three times current L1 throughput.

Deep Dive

1. What The Alert Is About

Ethereum developers have issued an alert to maintainers of L1 contracts about the Glamsterdam hard fork, which includes gas repricing proposals EIP-8037 and EIP-8038. These change the cost of creating and accessing on-chain state across the execution layer, based on replayed mainnet transactions that revealed a small set of sensitive contracts.

Coverage of the alert notes that developers identified at-risk contracts by replaying historical transactions with the new gas schedule, and are doing direct outreach to the most affected builders ahead of Glamsterdams activation in Q4 2026. This alert is framed as preventive: most contracts are expected to keep working, but a minority could revert or degrade.

2. Which Contracts Are At Risk And Why

Reports highlight three main risk patterns for L1 contracts under the new gas pricing. First, contracts that rely on the 2,300-gas stipend (for example when forwarding ETH via `call`) may not have enough gas once state access becomes more expensive. Second, contracts that hardcode fixed gas budgets for internal calls can run out of gas when costs for storage or account access increase. Third, logic that depends on precise `gasleft` values can misbehave when underlying opcodes are repriced.

Ethereum developers say many failing cases can be remedied by raising transaction or call-level gas limits, or by replacing brittle assumptions with safer, more dynamic gas handling. Regular users are expected to be shielded by updated wallets and infrastructure that adjust gas estimates automatically, but app developers need to patch their own contract code.

3. Why This Matters For Throughput And What To Watch

Glamsterdam is part of Ethereums roadmap to scale L1 by making larger blocks feasible, with developers targeting a post-upgrade gas limit around 200 million versus roughly 60 million today, according to high-level upgrade previews. The gas repricing in EIP-8037 and EIP-8038 is intended to keep long-term state growth manageable while enabling this higher capacity.

Ahead of mainnet activation, devs are encouraging contract authors to test on dedicated devnets such as Platberget (glam-devnet-8), followed by public testnets like Sepolia and Hoodi, where these changes will roll out first. The key milestones to watch are stable devnet behavior, successful public testnet forks, and final core dev calls that confirm the exact mainnet date and scope.

Conclusion

Ethereums decision to alert L1 contract maintainers ahead of Glamsterdam reflects a deliberate attempt to avoid surprise breakage as gas pricing for state operations is updated. The direct outreach, devnet testing, and focus on at-risk patterns such as hardcoded gas stipends show that most issues are localized and fixable, rather than systemic. For developers and advanced users, the key is to review gas assumptions and test on upcoming networks, so they can benefit from higher L1 capacity without unexpected failures when Glamsterdam ships.