Boost+: Equitable, Incentive-Compatible Block Building

Mengqian Zhang, Sen Yang (Yale University), Kartik Nayak (Duke University), Fan Zhang (Yale University)

Abstract

Block space on the blockchain is scarce and must be allocated efficiently through block building. However, Ethereum’s current block-building ecosystem, MEV-Boost, has become highly centralized due to integration, which distorts competition, reduces blockspace efficiency, and obscures MEV flow transparency. To guarantee equitability and economic effi- ciency in block building, we propose Boost+, a system that decouples the process into collecting and ordering transactions, and ensures equal access to all collected transactions. The core of Boost+ is the mechanism M_Boost+, built around a default algorithm. M_Boost+ aligns incentives for both searchers (intermediaries that generate or route transactions) and builders: Truthful bidding is a dominant strategy for all builders. For searchers, truthful reporting is dominant when- ever the default algorithm wins, and remains dominant for all conflict-free transactions, even when builders may win. We further show that even if a searcher can technically integrate with a builder, non-integration combined with truthful bidding still dominates any deviation for conflict-free transactions. We also implement a concrete default algorithm informed by em- pirical analysis of real-world transactions and evaluate its efficacy using historical transaction data.