Polaris runs an Ethereum mainnet-equivalent VM on top of a L1 host chain. With a modular plugin-based architecture, Polaris enables any host chain (e.g. Cosmos SDK-based chains, Polkadot, etc.) to execute Ethereum transactions on smart contracts. The application of the host chain only needs to implement the plugins (Configuration, State, Block, Precompile, Gas, Tx Pool) so that Polaris Core can run state transitions in accordance with mainnet EVM.
Stateful precompiles are a special type of EVM contract that are invoked from the EVM like a normal contract, but are executed in the native host chain. The Precompile Plugin is responsible for registering and running stateful contracts on the host chain; Polaris Core uses this plugin during the execution of Ethereum state transitions.
Polaris uses a custom implementation of the Ethereum state database (StateDB) which is injected into the EVM execution environment. The StateDB tracks and stores the Ethereum state (accounts, storage, and code); the State Plugin allows the host chain to handle this data.