What Is Glamsterdam? Ethereum’s 2026 Upgrade to On-Chain Block Building Explained
Ethereum’s last two major upgrades were focused squarely on Layer 2s. Glamsterdam, targeted to ship in H1 2026, is about improving Layer 1 — not just in terms of speed and efficiency but also the entire block production process. With execution increasingly migrating to L2s and Ethereum itself taking shape as the ecosystem’s underlying settlement and coordination layer, the question of who controls block production and under what rules is more important now than ever.

