Modular Blockchain
An architecture splitting a blockchain's jobs — execution, settlement, consensus, data — across specialized layers.
A modular blockchain separates the core functions a chain performs — execution (running transactions), settlement (finalizing and resolving disputes), consensus (ordering), and data availability — into distinct, specialized layers rather than one chain doing everything (“monolithic”). Ethereum plus its rollups is the leading modular stack: rollups execute, Ethereum settles and provides data availability.
The thesis is that specialization scales better — each layer optimizes for its job, and layers can be mixed and matched. The counter-thesis (championed by monolithic chains like Solana) is that modularity adds complexity, fragmentation, and cross-layer risk. This modular-versus-monolithic debate is one of the defining architectural arguments of 2020s crypto, with real trade-offs on both sides rather than a settled answer.