2025-09-12 –, Plasma Stage
Language: English
EIP‑2926 introduces a novel chunk-based code merkleization design for Ethereum. Instead of proving the entire contract, bytecodes are split into fixed-size chunks and committed into a Merkle Patricia Trie (MPT). This approach significantly reduces witness sizes, lowers resource consumption for ZK-EVM provers, and decreases network bandwidth requirements for stateless clients.
In this session, we dive into EIP‑2926’s chunk-based code merkleization, a transformative upgrade for Ethereum’s contract execution model. Instead of bundling full bytecode verification, EIP‑2926 breaks smart contracts into fixed-size chunks, commits them in a Merkle Patricia Trie, and stores a compact codeRoot in the contract account. 
Attendees will discover:
• Why this matters: Bytecode is currently one of the largest contributors to witness size. By introducing code chunking, Ethereum moves toward drastically leaner proofs suited for stateless clients and ZKEVM provers. 
• How it works: Learn about the fixed-size chunking strategy (typically 31 bytes), the use of first-instruction offsets (FIO), and the Merkleization mechanics that support efficient and provable code access. 
• Operational transition: The proposal details an upgrade path—including hard fork migration strategies—so that legacy contracts are incrementally converted without disruption. 
• Performance gains and trade-offs: We’ll unpack how only executed chunks need to be loaded, dramatically cutting down on bandwidth and proof size.
• Current status: Recently revived into the Glamsterdam workflow in mid‑2025, EIP‑2926 is gaining traction as essential infrastructure for future ZKEVM compatibility. 
Member of Stateless Consensus @ Ethereum Foundation