# Variables
ErrExistingGenesisState is an error when the user attempts to save a different genesis state when one already exists in a database.
# Interfaces
Database interface with full access.
HeadAccessDatabase defines a struct with access to reading chain head data.
NoHeadAccessDatabase defines a struct without access to chain head data.
ReadOnlyDatabase defines a struct which only has read access to database methods.
SlasherDatabase interface for persisting data related to detecting slashable offenses on Ethereum.