More than 100 Ethereum core contributors convened in Longyearbyen, Svalbard, for the Soldøgn Interop, a week-long focused effort to harden the upcoming Glamsterdam network upgrade. The event, held above the Arctic Circle, concluded with the group achieving its three primary objectives: agreement on a post-Glamsterdam gas limit floor of 200 million, stable ePBS implementations running with external builders, and final repricing numbers for EIP-8037 locked in.
The choice of Svalbard was deliberate, as it is one of the few visa-free locations for all nationalities and hosts the Global Seed Vault and Arctic World Archive, which store backups of Ethereum's source code. The region's 24/7 sunlight from late April through August also provided an apt metaphor for Ethereum's continuous operation, which developers leveraged throughout the week.
Key Technical Milestones
The ePBS track focused on restructuring slots with explicit deadlines for block construction, payload reveal, and attestations, creating more headroom for execution. Teams initially aimed for a 4 EL × 4 CL devnet by Monday evening, but after surfacing issues, a stable 4×3 configuration was running by Tuesday. The rest of the week was spent stress-testing and fixing cross-client edge cases, culminating in nearly all clients running together on glamsterdam-devnet-2 with the external builders pipeline tested end-to-end by Friday.
On the execution layer, the BAL optimizations track ran on separate devnets to avoid entanglement with consensus-layer work. Each optimization was feature-flagged, allowing isolated benchmarking. The team focused on raising the slowest paths first, using a dashboard and leaderboard to identify worst-case scenarios across clients.
Gas repricing efforts centered on EIP-8037, which increases the cost of writing new state to prevent unbounded state growth at higher gas limits. Early in the week, teams agreed to replace dynamic per-state-byte pricing with a fixed cost per state byte, simplifying testing. The accounting model evolved through several iterations, ultimately settling on opcode-level accounting by Thursday. By Friday, the spec stabilized on bal-devnet-6, with final repricing numbers delivered.
The convergence of these threads produced the headline number: a credible 200 million post-Glamsterdam gas limit floor. This increase is enabled by ePBS structuring slots to give execution more time, BAL optimizations providing throughput headroom, and EIP-8037 ensuring state growth remains controlled.
Other Glamsterdam Decisions
Beyond the main tracks, breakout sessions finalized several smaller EIPs. EIP-8061 (exit/consolidation churn increase) was included in glamsterdam-devnet-1, while EIP-8080 (exits via consolidation queue) was declined. EIP-8045 was scoped down to proposer duties within the look-ahead window, and EIP-7688 remains in scope but is held out of the first devnet pending work on bounded gossip-message sizes. EIP-8237 was deferred out of Glamsterdam to preserve optionality for a future 'top-up sync' architecture.
Hardening was a constant theme, with sessions covering fork-choice compliance testing, reproducible edge-case scenarios, and a demo of buildoor, an external-builder testing tool. Looking beyond Glamsterdam, a proposal-agnostic session on native account abstraction explored requirements for future designs, including alternative signature schemes, aggregation, and gas sponsorship.
