Glossary
Execution Layer
The part of a post-Merge Ethereum node that runs the EVM, processes transactions, updates state, and manages the mempool — paired with a separate consensus layer.
The execution layer is the half of an Ethereum node responsible for handling transactions: it gathers pending transactions from the mempool, runs them through the EVM, applies the resulting state changes, and computes the new state root. Clients such as Geth, Nethermind, Reth, Erigon, and Besu implement this layer.
Since the Merge, execution and consensus are split into two separate clients that talk over the Engine API. The execution layer builds and validates the transaction contents of a block, while the consensus layer (the beacon chain) decides which block is canonical, selects proposers, and finalizes checkpoints. This separation lets each layer evolve independently and lets operators mix and match client implementations for greater network resilience.