Settlement Layer
The base blockchain where transactions achieve final, authoritative settlement — the bedrock of a modular stack.
A settlement layer is the foundational blockchain where transactions reach final, authoritative resolution and where disputes are ultimately settled. In the modular model, rollups handle execution but rely on a settlement layer (Ethereum, most prominently) to anchor their security and finalize state.
The role demands maximal security and credible neutrality over raw speed — which is exactly what Ethereum and Bitcoin optimize for. A settlement layer’s value comes from being the trusted base that many higher layers build on, accruing security and value as more activity settles to it. The concept reframes the “slow and expensive” critique of base chains: they’re not trying to be fast execution environments, but reliable bedrock.